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Digitized  by  the  Internet  Archive 

in  2009  with  funding  from 

Boston  Library  Consortium  IVIember  Libraries 


http://www.archive.org/details/glaciallakeagassOOupha 


LIBRARY  CATALOGUE  SLIPS. 

United  States.     Dejxirlmcnt  of  the  interior.     (  U.  S.  geological  survey.) 

Uepartmeut  of  the  iuterior  |  —  |  Monographs  |  of  the  |  United 
Stiites  geological  survey  |  Volume  XXV  |  [Seal  of  the  depart- 
ment] I  Washington  |  government  printing  office  |  1895 

Second  title:  United  States  geological  survey  |  Charles  D. 
Walcott,  director  |  —  |  The  |  glacial  lake  Agassiz  |  by  |  Warren 
Uphaiu  I  [Vignette]  | 

Washington  |  government  printing  office  |  1895 

4°.    XXIV,  658  pp.   38  pi. 


tJpham  (Warren). 

United    States   geological    survey    |    Charles   D.   Walcott,    di- 
rector I   —  I  The  I  glacial  lake  Agassiz  |  by  |  Warren  Upham  | 
[Vignette]  | 
Washington  |  government  printing  office  |  1895 

i°.     XXIV,  058  pp.    38  pi. 

[0NITEI>  States.    Department  of   the  interior.     {V.   S.   geoloi/ical  survey. i 
ilonograpii  XXV.] 


United  States  geological  survey  |  Charles  D.  Walcott,  di- 
rector I  —  I  The  I  glacial  lake  Agassiz  |  by  |  Warren  Upham  | 
[Vignette]  | 

Washington  |  government  printing  office  |  1895 

40.    XXIV,  668  pp.    38  pi. 

[United  States.    Department  of   the  interior.      i,U.   S.  geolo<jical  survey.) 
Monograph  XXV.] 


^D^ERTISBJVtENT. 

[Monograph  XXV.] 


The  publications  of  the  United  States  Geological  Survey  are  issued  in  accordance  with  the  statute 
approved  Mari-li  3,  1879,  wliich  declares  that — 

"The  publicatiiiiia  of  the  Geological  Survey  shall  consist  of  the  annual  report  of  operations,  geo- 
logical and  eoonouiic  nia|is  illustrating  the  resources  and  classification  of  the  lauds,  and  reports  upon 
general  and  economic  geology  and  paleontology.  The  annual  report  of  operations  of  the  Geological 
Survey  shall  accompany  the  annual  report  of  the  Secretary  of  th(!  luterior.  All  special  memoirs  and 
reports  of  said  Survey  shall  be  issued  in  uniform  quarto  series  if  deemed  necessary  by  the  Director,  but 
otherwise  in  ordinary  octavos.  Three  thousand  copies  of  each  shall  be  puldished  for  scientific  exchauges 
and  for  sale  at  thepriceof  pulilication;  and  all  literary  .and  cartographic  materials  received  in  exchange 
shall  be  the  property  of  the  United  States  and  form  a  part  of  the  library  of  the  organization :  Aiul  the 
money  resulting  from  the  sale  of  sach  publications  shall  be  covered  into  the  Treasury  of  the  United 
States." 

The  following  joint  resolution,  referring  to  all  govoruraont  publications,  was  passed  by  Congress 
July  7,  1882: 

"That  whenever  any  <locument  or  report  shall  be  ordered  printed  by  Congress,  there  shall  be 
printed,  in  addition  to  the  number  in  each  case  stated,  the  '  usual  number '  (1,900)  of  copies  for  binding 
and  distribution  among  those  entitled  to  receive  them." 

Except  in  those  cases  in  whicli  an  extra  number  of  any  publication  has  been  supplied  to  the  Sur- 
vey by  special  resolution  of  Congress  or  has  been  ordered  by  the  Secretary  of  the  Interior,  this  office 
has  no  copies  for  gratuitons  distribution. 

ANNUAL  REPORTS. 

I.  First  Annual  Report  of  the  United  States  Geological  Survey,  by  Clarence  King.  1880.  8°.  79 
pp.     1  ma]). — A  preliminary  report  describing  plan  of  organization  and  publications. 

II.  Second  Annual  Report  of  the  United  States  Geological  Survey,  1880-'81,  by  J.  W.  Powell, 

1882.  S°.     Iv,  .588  p]).     «2  pi.     1  map. 

III.  Third  Annual  Report  of  the  United  States  Geological  Survey,  1881-'82,  by  .J.  W.  Powell. 

1883.  8^.     xviii,  564  pp.     67  pi.  and  maps. 

IV.  Fourth  Annual  Rei.ort  of  the  United  States  Geological  Survey,  1882-'83,  by  ,1.  \V.  Powell. 

1884.  8".     xxxii,  473  pp.     8.5  pi.  and  maps. 

V.  Fifth   Annual   Report  of  the  United   States   Geological    Survey,  1883-'84,  by  J.  \V.  Powell. 

1885.  8'^.     xxxvi,  469  pp.     58  pi.  and  maps. 

VI.  Sixth  Annual  Report  of  the  United  States  Geological  Survey,  1884-8.5,  by  .T.  W.  Powell. 
1885.     8".     xxix,  570  pp.     65  pi.  and  maps. 

VII.  Seventh  Annual  Rep<ut  of  the  United  States  Geological  Survey,  1885-'86,  by  .1.  \Y.  Powell. 

1888.  8^'.     XX,  656  pp.     71  pi.  and  maps. 

VIII.  Eighth  Annual  Report  of  the  United  States  Geological  Survey,  1886-'87,  by  .T.  \V.  Powell. 

1889.  8".     2  v.     xix,  474,  xii  ]ip.     53  pi.  and  maps;  1  p.  1.     475-1063  pp.     54-76  pi.  and  mjips. 

IX.  Ninth   Annu,al  Rci)ort  of  the  United  States  (ieological  Survev,  1887-'88,  by  .J.  W.  Powell. 

1889.  8^'.     xiii,717pp.     88  pi.  and  maps. 

X.  Tenth   Annual    Report  of  the  United  States   Geological   Survev,  1888-'89,  by  .1.  W.  Powell. 

1890.  8"^.     2v.     XV,  774  pp.     98  pi.  and  maps;  viii,  123  p]i. 

XI.  Eleventh  Annual  Report  of  the  United  States  Geological  Survey,  1889-'90,  by  J.  W.  Powell. 

1891.  8^.     2  V.     XV,  7.57  jip.     66  pi.  and  maps;  ix,  351pp.     30  pi.  and  maps. 

XII.  Twelfth  Annual  Report  of  the  United  States  Geological  Snrvey,  1890-'91,  by  .J.  W.  Powell. 
1891.     8".    2  V.     xiii,  675  pj).     .53  pi.  and  maps;  xviii,  576  pp.     146  ])1.  and  maps. 

XIII.  Thirteenth  Annual  Report  of  the  United  States  Geological  Survev,  1891-'92,  by  .1.  W. 
Powell.  1893.  8".  3  v.  vii,  240  pp.  2 maps ;  x,  372  pp.  105  pi.  and  maps;  xi,  486  pp.  77  pi.  and 
maps. 

XIV.  Fourteenth  Annual  Report  of  the  United  States  Geological  Snrvey,  1892-'93,  by  .1.  W. 
Powell.    1893.     8°.     2  v.     vi,  321  pp.     1  pi. ;  xx,  ,597  pp.     74  pi. 

XV.  Fifteenth  Annu.al  Report  of  the  United  States  Geological  Survey,  1893-'94,  by  J.  W.  Powell. 
1895.     8'^.     xiv,755pp.     48  pi. 

I 


II  ADVERTISEMENT. 

MONOGRAPHS. 

I.  Lake  Bonneville,  by  Grove  Karl  Gilbert.     1890.     4°.     xx,  438x)p.     .51  pi.     Imap.     Price  $1.50. 

II.  Tertiary  Hi.story  of  the  Grauil  Cafiou  District,  with  atlas,  bv  Clarence  E.  Dutton,  Capt.,  U.  S.  A 
1882.     4°.     xiv,  264  pp.     42  pi.  and  atlas  of  24  sheets  folio.     Price  $10.00. 

III.  Geolojiy  of  the  Conistock  Lode  and  the  Washoe  District,  with  atlas,  by  George  F.  Becker. 
1882.     4°.     sv,  422  pp.     7  pi.  and  atlas  of  21  sheets  folio.     Price  $11.00. 

IV.  Comstock  Mining  anil  Miners,  by  Eliot  Lord.     1883.     4°.     xiv,  451  pp.     3  pi.     Price  $1.50. 

V.  The  Copper-Bearing  Kocks  of  L.ake  Superior,  by  Roland  Duer  Irving.  1883.  4^^.  xvi,  464 
pp.     15  1.     29  pi.  and  maps.     Price  $1.85. 

VI.  Contribntions  to  the  Knowledge  of  the  Older  Mesozoic  Flora  of  Virginia,  by  William  Morris 
Fontaine.     1883.     4^^.     xi,  144  pp.     .54  1.     54  pi.     Price  $1.05. 

VII.  Silver-Lead  Deposits  of  Eureka,  Nevada,  by  Joseph  Storv  Curtis.  1884.  4°.  xiii,  200  pp. 
16  pi.     Price  $1.20. 

VIII.  Paleontology  of  the  Eureka  District,  by  Charles  Doolittle  Walcott.  1884.  4°.  xiii,  298 
pp.     24  1.     24  pi.     Price  $1.10. 

IX.  Brachiopoda  and  Lamellibranchiata  of  the  Raritan  Clays  and  Greensand  Marls  of  New 
Jersey,  by  Robert  P.  Whittield.     1885.     4".     xx,  338  pp.     35  pi.     1  m.ap.     Price  $1.15. 

X.  Dinocerata.  A  Monograph  of  an  Extinct  Order  of  Gigantic  Mammals,  by  Othniel  Charles 
Marsh.     1886.     4'-\     xviii,  243  pp.     56 1.     .56  pi.     Price  $2.70. 

XI.  Geological  History  of  Lake  Lahontaii,  a  Onateruary  Lake  of  Northwestern  Nevada,  by 
Israel  Cook  Russell.     1885.     4':.     xiv,  288  pp.     46  pi.  and  niajis.     Price  $1.75. 

XII.  Geology  and  Mining  Industry  of  Leadville,  Colorado,  with  atlas,  by  Samuel  Franklin  Em- 
mons.    1886.     4'-\  ■  xxix,  770  pp.     45  pl.'aud  atlas  of  35  sheets  folio.     Price  $8.40. 

XIII.  Geology  of  the  Quicksilver  Dejiosits  of  the  P.acitic  Slope,  with  atlas,  bv  George  F.  Becker. 
1888.     4-^.     xix,  486  pp.     7  pi.  and  atlas  of  14  sheets  folio.     Price  $2.00. 

XIV.  Fossil  Fishes  and  Fossil  Plants  of  the  Triassic  Rocks  of  New  .Jersey  and  the  Connecticut 
Valley,  by  .John  S.  Newberry.     1888.     4°.     xiv,  152  pp.     26  pi.     Price  $1.00.      ' 

XV.  The  Potomac  or  Younger  Mesozoic  Flora,  bv  William  Morris  Fontaine.  1889.  4-',  xiv, 
377  pp.     180  pi.     Text  and  plates  biiund  separately.     Price  $2..50. 

XVI.  The  Paleozoic  Pishes  of  North  America,  by  John  Strong  Newberry.  1889.  4°.  340  pp. 
53  pi.     Price  $1.00. 

XVII.  The  Flora  of  the  Dakota  Gronji,  a  posthumous  work,  by  Leo  Lesquereux.  Edited  by  F. 
H.  Knowltou.     1891.     4'^'.     400  pp.     66  id.     Price  .$1.10. 

XVIII.  Gasteropoda  and  Cei>halo]i(ida  of  the  Raritan  Clays  and  Grecns.and  Marls  of  New  Jersey, 
by  Robert  P.  Whittield.     1891.     4'.     402  p]).     50  pi.     Price  $1.00. 

XIX.  Th<>  Penokee  Iron-Bearing  Series  of  Northern  Wisconsin  and  Michigan,  by  Roland  D. 
Irving  and  C.  R.  Van  Hisc.     1892.     I"-",     xix,  .534  pp.     Price  $1.70. 

XX.  Geology  of  the  Eureka  District,  Nevada,  with  an  atlas,  by  Arnold  Hague.  1892.  4'^.  xvii, 
419  pp.     8  pi.     I'rice$5.25. 

XXI.  The  Tertiary  Rhynchophorous  Coleoptera  of  the  United  States,  by  Samuel  Hubbard  Scud- 
der.     1893.     4^'.     xi,  206  ])p.     12  i)l.     Price  90  cents. 

XXII.  A  Maniuil  of  Topographic  Methods,  liy  Henry  Gannett,  chief  topographer.  1893.  4°. 
XIV.  300])p.     18  pi.    Price  $1.00. 

XXIII.  Geology  of  the  (ireeu  Mountains  in  Massachusetts,  by  Raphael  Pumpelly,  T.  Nelson  Dale, 
and  J.  E.  W(dtt'.     1894.     4-^.     xiv,  206  pp.     23  pi.     Price  $1.30. 

XXIV.  MoUusca  and  Crustacea  of  the  Miocene  Formations  of  New  Jersey,  by  Robert  Parr 'Whit- 
field.    1894.     4°.     193  pp.     24  pi.     Price  90  cents. 

XXV.  The  Glacial  Lake  Agassiz,  by  Warren  Upham.    1895.   4"=.    xxiv,  658  pp.   38  pi.   Price  $1.70. 

XXVI.  Flora  of  the  Amboy  Clays,  by  John  Strong  Newberry ;  a  posthumous  work,  edited  by 
Arthur  Hollick. 

In  ])reparation : 

— The  Geology  of  Franklin,  Hampshire,  and  Hampden  counties,  Massachusetts,  by  Benjamin 

ICeudall  Emerson. 
— The  Glacial  Gravels  of  Maine  and  their  associated  deposits,  by  George  H.  Stone. 
—Geology  of  the  Denver  Basin,  Colorado,  by  S.  F.  Emmons,  Wlutman  Cross,  and  Geo.  H.  Eldridge. 
— Sauropfida,  by  O.  C.  Marsh. 
— Stegosanria,  by  O.  C.  Marsh. 
— Broutotherida".,  by  O.  C.  Marsh. 
— Report  on  Silver  Cliff  and  Ten-Mile  Mining  Districts,  Colorado,  by  S.  F.  Emmons. 

BULLETINS. 

1.  On  Hypersthene-Andesite  and  on  Triclinic  Pyroxene  in  Angitic  Rocks,  by  Whitman  Cross, 
with  a  Geological  Sketch  of  Buffalo  Peaks,  Colorado,  by  S.  F.  Ennnons.  1883.  '8>^.  42  jjp.  2  pi. 
Price  10  cents. 

2.  Gold  and  Silver  Conversion  Tables,  giving  the  coining  values  of  troy  ounces  of  fine  metal,  etc., 
computed  by  Albert  Williams,  jr.     1883.     8'^.     8  pji.     Price  5  cents. 

3.  On' the  Fossil  Faunas  of  the  Upper  Devonian,  along  the  meridian  of  76^  30',  from  Tompkins 
County,  N.  Y.,  to  Bradford  County,  Pa.,  by  Henry  S.  Williams.     1884.     8°.     36  pp.     Price  5  cents. 

4.  On  Mesozoic  Fossils,  by  Charles  A.  White.     1884.     8^.     36  pp.     9  pi.     Price  5  cents. 

5.  A  Dictionary  of  Altitudes  in  the  United  States,  compiled  bv  Henry  Gannett.  1884.  8=.  325 
pp.     Price  20  cents. 


ADVERTISEMENT.  Ill 

6.  Elevations  in  the  Dominion  of  Canada,  by  J.  W.  Spencer.     1884.     8°.     43  pp.     Price  5  cents. 

7.  Mapoteca  Geologica  Americana.  A  C'atiilogue  of  Geolotjical  Maps  of  America  (North,  and 
Sonth),  1752-1881,  in  geographic  and  chronologic  order,  by  Jules  Marcou  and  John  Belknap  Marcou. 

1884.  8°.     184  pp.     Price  10  cents. 

8.  On  Secondary  Enlargements  of  Mineral  Fragments  in  Certain  Rocks,  by  R.  D.  Irving  and  C. 
E.  Van  Hise.     1884.     S^.     .56  pp.     6  pi.     Price  10  ceiits. 

9.  A  report  of  work  done  in  the  Washington  Laboratory  during  the  fiscal  year  1883-'84.  F.W. 
Clarke,  chief  chemist;  T.  M.  Chatard,  assistant  chemist.      1884.      S'~'.      40  pp.      Price  5  cents. 

10.  (Jn  tlie  Cambrian  Faunas  of  North  America.  Preliminary  studies,  by  Charles  Doolittle  Wal- 
cott.      1884.      8>^'.      74  pp.      10  pi.      Price  5  cents. 

11.  On  the  Quaternary  and  Recent  Mollusca  of  the  Great  Basin;  with  Descriptions  of  New 
Forms,  by  R.  Ellsworth  Call.  Introduced  by  a  sketch  of  the  Quaternary  Lakes  of  the  Great  Basin, 
by  G.  K.  Gilbert.     1884.     8°.     66  i)p.     6  pi.  '  Price  5  cents. 

12.  A  Crystallographic  Study  of  the  Thinolite  of  Lake  Lahontan,  by  Edward  S.  Dana.  1884.  8°. 
34  pji.     3  pi.     Price  5  cents. 

13.  Boundaries  of  the  United  States  and  of  the  several  States  and  Territories,  with  a  Historical 
Sketch  of  the  Territorial  Changes,  by  Henry  Gannett.     1885.     8°.     135  pp.     Price  10  cents. 

14.  The  Electrical  and  Magnetic  Properties  of  the  Iron-Carburets,  l)y  Carl  Barns  and  Vincent 
■  Stronhal.     1885.     8".    238  pp.     Price  15  cents. 

15.  On  the  Mesozoic  and  Cenozoic  Paleontology  of  California,  by  Charles  A.  White.  1885.  8°. 
33  pp.     Price  5  cents. 

16.  On  the  Higher  Devonian  Faunas  of  Ontario  County,  New  York,  by  .John  M.  Clarke.  1885.  8°. 
86  pp.     3  pi.     Price  5  cents. 

17.  On  the  Development  of  Crystallization  in  the  Igneous  Rocks  of  Washoe,  Nevada,  with  Notes 
on  the  Geology  of  the  District,  by  Arnold  Hague  and  Joseph  P.  Iddings.  1885.  S°.  44  pp.  Price  5 
cents. 

18.  On  Marine  Eocene,  Fresh- water  Miocene,  and  other  Fossil  Mollusca  of  Western  North  America, 
by  Charles  A.  White.     1885.    8'^.     26  pp.     3  pi.     Price  5  cents. 

19.  Notes  (m  the  Stratigraphy  of  California,  by  George  F.  Becker.    1885.    8".    28  pp.    Price  5  cents. 

20.  Contributions  to  the  Mineralogy  of  the  Rocky  Jlountaius,  by  Whitman  Cross  and  W.  F.  Hille- 
brand.     1885.     8^.     114  pp.     1  pi.     Price' 10  cents. 

21.  The  Lignites  of  the  Great  Sioux  Reservation;  a  rejiort  on  the  Region  between  the  Grand 
and  Moreau  Rivers,  Dakota,  by  Bailey  Willis.     1885.     8°.     16  pp.     5  jd.     Price  5  cents. 

22.  On  New  Cretaceous  Fossils  from  California,  by  Charles  A.  White.  1885.  8°.  25  pp.  5  pi. 
Price  5  cents. 

23.  Observations  on  the  .Jun(-tion  between  the  Eastern  Sandstone  and  the  Keweenaw  Series  on 
Keweenaw  Point,  Lake  Superior,  by  R.  D.  Irving  and  T.  C.  Chamberlin.  1885.  8'^'.  124  pp.  17  pi. 
Price  15  cents. 

24.  List  of  Marine  Mollusca,  comprising  the  Quaternary  fossils  and  recent  forms  from  American 
Localities  between  Cape  Hatteras  and  Cape  Roqne,  including  the  Bermudas,  by  William  Healey  Dall. 

1885.  S°.     336  pp.     Price  25  cents. 

25.  The  Present  Technical  Condition  of  the  Steel  Industry  of  the  United  States,  by  Phineas 
Barnes,     1885.     8>-\     85  pp.     Price  10  cents. 

26.  Copper  Smelting,  by  Henry  M.  Howe.     1885.     8°.     107  pp.     Price  10  cents. 

27.  Report  of  work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  fiscal  year 
1884-'85.     1886.     8°.     80  pp.     Price  10  cents. 

28.  The  Gabbros  and  Associated  Hornldende  Rocks  occurring  in  the  Neighborhood  of  Baltimore, 
Md.,  by  George  Huntington  Williams.     1886.     8'-.     78  pp.     4  ]d.    Price  10  cents. 

29.  On  the  Fresh- water  Invertebrates  of  the  North  American  Jurassic,  by  Charles  A.  White.  1886. 
8'^.     41  pp.     4  pi.     Price  5  cents. 

30.  Second  Contribution  to  the  Studies  on  the  Cambrian  Faunas  of  North  America,  by  Charles 
Doolittle  Walcott.     1886.     8".     369  pp.     33  pi.     Price  25  cents. 

31.  Systematic  Review  of  our  Present  Knowledge  of  Fossil  Insects,  including  Myriajiods  and 
Arachnids,  by  Samuel  Hubbard  Scudder.     1886.     8^^.     128  pp.     Price  15  cents. 

32.  Lists  and  Analyses  of  the  Sliueral  Springs  of  the  United  States;  a  Preliminary  Study,  by 
Albert  C.  Peale.     1886.     8'^.     235  pp.     Price  20  cents. 

33.  Notes  on  the  Geology  of  Northern  California,  by  J.  S.Diller.     1886.    8^.    23  pp.    Price  5  cents. 

34.  On  the  Relation  of  the  Laramie  Molluscau  Fauna  to  that  of  the  succeeding  Fresh- water  Eocene 
and  other  groups,  by  Charles  A.  White.     1886.     8'-.     54  jip.     5  jil-     Price  10  cents. 

35.  Physical  Properties  of  the  Iion-Carburets,  by  Cail  Barus  ami  Vincent  Stronhal.  1886.  8'-"'. 
62  pp.     Price  10  cents. 

36.  Subsidenceof  Fine  Solid  Particles  in  Licjuids,  by  Carl  Barus.    1886.    8".    58pp.    Price  lOcents. 

37.  Types  of  the  Laramie  Flora,  by  Lester  F.  AVard.     1887.     8^.     351pp.     57  pi.     Price  25  cents. 

38.  PeridotiteofElliottCounty,  Kentucky,  by  J.  S.Diller.     1887.     8-\    31pp.     ipl.    Price5ceut8. 

39.  The  Upper  Beaches  and  Deltas  of  the  (ilacial  Lake  Agassiz,  by  Warren  Uphani.  1887.  S^. 
84  pp.     1  pi.     Price  10  cents. 

40.  Changes  in  River  Courses  in  Washington  Territo<-v  due  to  Glaciatiou,  by  Bailcv  Willis.  18,S7. 
8°.     10  pp.     4  pi.     Price  5  cents. 

41.  On  the  Fossil  Faunas  of  the  Upper  Devonian — the  Genesee  Section,  New  York,  by  Henry  S. 
Williams.     1887.     8".     121  pp.     4  pi.     Price  15  cents. 

42.  Report  of  work  doiK^  in  the  Division  of  Chenustry  and  Physics,  mainly  during  the  fiscal  year 
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IV  ADVERTISEMENT. 

43.  Tertiary  and  Cretaceous  Strata  of  thi'  Tuscaloosa,  Torabigbee,  and  Alabama  Rivers,  by  Eugene 
A.  Smith  anrt-Liiwrenco  C. Johnson.     1887.     8^.     189  pp.     21  pi.     Price  15  cents. 

44.  Bibliogriiphy  of  North  American  Geology  for  188G,  by  Nelson  H.  Darton.  1887.  S°.  35  pp. 
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47.  Analyses  of  Waters  of  the  Yellowstone  National  Park,  with  an  Account  of  the  Methods  of 
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48.  On  the  Form  and  Position  of  the  Sea  Level,  by  Robert  Simpson  Woodward.  1888.  8'^.  88 
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50.  Formulas  and  Tables  to  Facilitate  the  Construction  and  Use  of  Maps,  by  Robert  Simpson 
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51.  On  Invertelirate  Fossils  from  the  Pacific  Coast,  by  Charles  Abiathar  White.  1889.  8-.  102 
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.52.  Subaerial  Decay  of  Rocks  and  Origin  of  the  Red  Color  of  Certain  Formatious.  by  Israel 
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,57.  A  Geological  Keconnoissance  in  Southwestern  Kansas,  by  Robert  Hay.  1890.  8^.  49  pp. 
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59.  The  Galibros  and  Associated  Rocks  in  Delaware,  by  Frederick  D.  Chester.  1890.  8'^.  45 
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60.  Report  of  work  done  iu  the  Division  of  Chemistry  and  Physics,  mainly  during  the  fiscal 
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61.  Contributions  to  the  Mineralogy  ot  the  Pacific  Coast,  by  William  Harlow  Melville  and  Wal- 
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63.  A  Bibliography  of  Paleozoic  Crustacea  from  1698  to  1889,  including  a  list  of  North  Amer- 
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65.  Stratigraphy  of  the  Bituminous  Coal  Field  of  Peniisvlvania,  Ohio,  and  West  Virginia,  by 
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66.  On  a  Group  of  Volcanic  Rocks  from  the  Tewan  Mountains,  New  Mexico,  and  on  the  occur- 
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67.  T!ie  Relations  of  the  Traps  of  the  Newark  System  in  th(^  New  Jersey  Region,  by  Nelson 
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68.  Earthquakes  in  California  in  1889,  by  James  Edward  Keeler.  1890.  S^.  25  pp.  Price  5 
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69.  A  Classed  and  Annotated  Biography  of  Fossil  Insects,  l>y  Samuel  Howard  Scudder.  1890. 
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70.  A  report  on  Astronomical  Work  of  1889  and  1890,  by  Robert  Simpson  Woo<hvar<I.  1890.  8^^. 
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71.  Index  to  the  Known  Fossil  Insects  of  the  World,  including  Myriapods  and  Arachnids,  by 
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72.  Altitiidi's  between  Lake  Superior  and  the  Rocky  Mountains,  by  Warren  rpham.  1891.  8'^. 
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73.  The  Viscosity  of  .Solids,  by  Carl  Barus.     1891.     8'-\     xii,  139  pp.     6  pi.     Price  15  cents. 

74.  The  Minerals  of  North  Carolina,  by  Frederick  Augustus  (Jenth.  1891.  8-.  119  pp.  Price 
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75.  Record  of  North  American  Geology  for  1SS7  to  1889,  inclusive,  by  Nelson  Horatio  Darton. 
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76.  A  Dictionary  of  .\ltitudes  in  the  Fnitei".  States  (second  edition),  compiled  by  Henry  Gannett, 
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ADVERTISEMENT.  V 

77.  The  Texan  Permian  and  its  Mesozoic  types  of  Fossils,  by  Charles  A.  White.     1891.     8°.     51 
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78.  A  report  of  work  done  in  the  Division  of  Chemistry  and  Physics,  mainly  during  the  fiscal 
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79.  A  Late  Volcanic  Eruption  in  Northern  California  and  its  peculiar  lava,  by  ,J.  (S.  Diller. 

80.  Correlation  papers — Devonian  and  Carboniferous,  bv  Henry  Shaler  Williams.     1891.     8°. 
279  pp.     Price  20  cents. 

81.  Correlation  papers — Cambrian,  by  Charles  Doolittle  Wah-ott.      1891.     8'  .     547  pp.      3  pi. 
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82.  Correlation  papers— Cretaceous,  by  Charles  A.  AVhite.     1891.     8*^.     '273  pp.     3  pi.     Price  20 
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83.  Correlation  papers— Eocene,  by  William  Bulloik  Clark.     1891.     8".     173  pp.     2  pi.     Price 
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90.  A  report  of  work  done  in  the  Division  of  Cheniistrv  and  Physics,  mainly  durinf;  the  liscal 
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91.  Record  of  North  American  Geology  for  1890,  by  Nelson  Horatio  Darton.     1891.     8'  .     88  pp. 
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92.  The  Compressibility  of  Liquids,  l)y  Carl  Barus.     1892.     8^'.     96  pp.     29  pi.     Price  10  cents. 

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94.  The  Mechanism  of  Solid  Viscosity,  by  Carl  Barus.      1892.     8=.     138  pp.     Price  15  cents. 

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97.  TheMesozoicEchinodermataoftheUnitedStates,  by  W.B.Clark.    1893.    8^.    207  iip.    50  pi. 
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98.'  Flora  of  the  Outlying   Carboniferous  Basins  of  Southwestern  Missouri,  bv  David  White. 
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101.  Insect  Fauna  of  the  Rhode  Island  Coal  Field,  by  Samuel  Hulibard  Scudder.     1893.     8°. 
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102.  A  Catalogue  and  Bibliography  of  North  American  Mesozoic  luvertebrata,  by  Cornelius 
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103.  High  Temperature  Work  in  Igneous  Fusion  and  EI)ullition,  chietiy  in  relation  to  pressure, 
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104.  Glaciatiou  of  the  Yellowstone  Valley  north  of  the  Park,  by  Walter  Harvey  Weed.    1893.    8°. 
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105.  The  Laramie  and  the  overlying  Livingstone  Formation  in  Moutana,  by  AValtcr  Harvey 
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106.  The  Colorado  Formation  and  its  Invertebrate  Fauna,  by  T.  W.  Stanton.     1893.     8^'.     288 
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107.  The  Trap  Dikes  of  Lake  Champlain  Valley  and  the  Eastern  Adiroudacks,  by  .lames  Furmau 
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108.  A  Geological  Eeconuoissance  in  Central  Wa.shington,  by  Israel  Cook  Russell.     1893.     8^. 
108  lip.     12  pi.     Price  15  cents. 

109.  The  Eruptive  and  Sedimentary  Rocks  on  Pigeon  Point,  Minnesota,  and  their  contact  phe- 
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110.  The  Paleozoic  Section  in  the  vicinity  of  Three  Forks,  Montana,  by  Albert  Charles  Peale. 
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111.  Geology  of  the  Big  Stone  Gap  Coal  Fields  of  Virginia  and  Kentucky,  by  Marius  R.  Camp- 
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112.  Earth(iuakeB  in  California  in  1892,  by  Charles  D.  Perrine.     1893.     8^.     57  pp.     Price  10 
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113.  A  report  of  work  done  in  the  Division  of  Chemistry  during  the  fiscal  years  1891-'92  and 
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114.  Earthquakes  in  California  in  1893,  by  Charles  D.  Perrine.    1894.    8'^.    23  pp.    Price  5  cents. 

115.  A  Geographic  Dictionary  of  Rhode  Island,  by  Henry  Gannett.     1894.     8°.     31  pp.     Price 
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116.  A  Geographic  Dictionary  of  Massachusetts,  by  Henry  Gannett.     1894.     8^'.     126  pp.     Price 
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117.  A  Geographic  Dictionary  of  Connecticut,  by  Henry  Gannett.     1894.     8*^.    67  pp.     Price  10 
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119.  A  Geological  Reconnoissance  in  Northwest  Wyoming,  by  George  Homans  Eldridge.     1894. 
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120.  Tlie  Devonian  System  of  Eastern  Pennyslvania  and  New  York,  by  Charles  S.  Prosser,     1894. 
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121.  A  Bibliography  of  North  American  Paleontology,  by  Charles  Rollin  Keyes.     1894.    8°.     251 
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122.  Results  of  Primary  Triangulation,  by  Henry  Gannett.     1894.     8^.     412  pp.     17  pi.     Price 

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123.  A  Dictionary  of  Geographic  Positions,  by  Henry  Gannett.     1895.     S'^.     183  pp.     1  pi.    Price 

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124.  Revision  of  North  American  Fossil  Cockroaches,  by  Samnel  Hubbard  Scudder.     1895.     8°. 
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125.  The  Constitution   of   the   Silicates,  by  Frank  Wigglesworth  Clarke.     1895.     8°.     109   pp. 
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128.  The  Bear  River  Formation  and  its  Characteristic  Fauna,  by  Charles  A.  White.     1895.     8-. 
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129.  Earthquakes  in  California  in  1894,  by  Charles  D.Perrine.    1895.     8°.     25  pp.     Price  5  cents. 

131.  Report  of  Progress  of  the  Division  of  Hydrography  for  the  calendar  years  1893  and  1894, 
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126.  A  Mineralogical  Lexicon,  of  Franklin,  Hampshire,  and  Hampden  counties,  Massachusetts, 
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127.  Catalogue  of  Contributions  to  Nojth  American  Geology,  1732-1894,  by  Nelson  Horatio 
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130.  Bibliography  and  Index  of  North  American  Geology,  Paleontology,  Petrology,  and  Miner- 
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132.  The  Disseminated  Lead  Ores  of  Southeastern  Missouri,  by  Arthur  Winslow. 

133.  Contributions  to  the  Cretaceous  Paleontology  of  the  Pacific  Coast:  The  Fauna  of  the 
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134.  The  Cambrian  Rocks  of  Pennsylvania,  by  Charles  Doolittle  Walcott. 

—  The  Moraines  of  the  Missouri  Coteau  and  their  attendant  deposits,  by  James  Edward  Todd. 

—  Volcanic  Rocks  of  South  Mountain,  Pennsylvania,  by  Florence  Bascom. 

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—  Geology  of  the  Castle  Mountain  Mining  District,  Montana,  by  W.  H.  Weed  and  L.  V.  Pirsson. 

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To  THE  Director  of  the 

United  States  Geological  Survey, 

Washington,  D.  C. 
Washington,  D.  C,  October,  1S95. 


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DEPARTMENT   OF    THE    INTERIOR 


MONOGRAPHS 


United  States  Geological  Survey 


VOLUME    XXY 


WASHINGTOI^ 

GOVERNMENT    PRINTING    OFFICE 
1896 


UNITED  STATES  GEOLOGICAL  SUUVEY 

CHARLES  D.  WALCOTT,  DIKECTOK 


THE 


GLACIAL   LAKE    AGASSIZ 


BY 


WARREN    UPHAM 


WASHINGTON 

GOVERNMENT    PRINTING    OFFICE 

1895 


CONTENTS. 


Page. 

Letter  of  transmittal xvii 

Preface xix 

Abstract  op  volume xxi 

Chapter  I. — Introduction 1 

Basin  of  tlie  Red  River  of  the  North  aud  of  Lake  Winnipeg 1 

The  Glacial  Lake  Agassiz 2 

Relationship  to  the  ice-sheet 3 

Early  observations  of  Lake  Agassiz 6 

Work  reported  in  this  monograph 7 

Chapter  II. — Topography  of  the  basin  of  Lake  Agassiz 14 

Outlet,  bed,  and  shores  of  Lake  Agassiz 15 

River  Warren 15 

The  Red  River  Valley 19 

Shore-lines 26 

Deltas 27 

Dunes 28 

Wooded  region  of  northern  Minnesota  and  of  Manitoba  and  Keewatin,  partly  covered 

by  this  lake 29 

Country  bordering  Lake  Agassiz  on  the  east 30 

Giants  Range 31 

Mesabi  Range 31 

Mesabi  and  Itasca  moraines 32 

Leaf  Hills 33 

Country  west  of  Lake  Agassiz 34 

The  Coteau  des  Prairies 36 

Ascent  from  the  Red  River  Valley  in  North  Dakota 39 

The  Manitoba  escarpment 40 

Pembina  Mountain '. : 40 

Tiger  Hills 42 

Riding  and  Duck  mountains 42 

Porcupine  and  Pasquia  hills 43 

Great  Bear  Hills 44 

Forest  and  prairie ■ 44 

Existing  lakes  within  the  area  of  Lake  Agassiz 46 

Lake  Winnipeg 47 

Lakes  Manitoba  and  Winnipegosis 48 

Rainy  Lake 49 

Lake  of  the  Woods 49 

Red  Lake 49 

V 


VI 


CONTENTS. 


Chapter  II. — Topography  ok  the  basin  of  Lake  Agassiz — Continued. 

Rivers  tributary  to  Lake  Agassiz  anil  draining  its  area 50 

Rainy  and  Winnijieg  rivers 50 

Red  Lake  River 52 

Red  River 54 

Sheyenne  River 56 

Langs  Valley 57 

Pembina  River 57 

Assiuibolne  River 58 

Qu' Appelle  and  Souris  rivers 59 

Little  Saskatchewan  or  Fairford  River 61 

Saskatchewan  River 61 

Smaller  tributaries  of  Lake  Winnipeg 62 

Nelson  River 62 

Extension  of  the  basin  of  Lake  Agassiz  by  glacial  lakes  outflowing  to  it  from  the  region  of 

the  Peace  and  Athabasca  rivers 63 

Chapter  III. — Geologic  formations  underlying  the  drift 65 

Archean  formations 65 

The  Archean  area  in  Minnesota 66 

Vicinity  of  the  Lake  of  the  Woods,  Rainy  Lake,  and  northward 67 

Boundary  of  the  Archean  toward  the  west 67 

Lower  Silurian  formations 68 

Outcrops  on  Lake  Winnipeg 69 

East  Selkirk 70 

Lower  Fort  Garry 71 

Stony  Mountain 71 

Little  Stony  Mountain 71 

Stonewall 72 

Upper  Silurian  and  Devonian  formations 72 

Sections  of  artesian  wells  in  Paleozoic  strata 74 

Well  at  Humboldt,  Minn 74 

Well  at  Grafton,  N.  Dak 77 

Well  at  Rosenfeld,  Manitoba 78 

Well  at  Morden,  Manitoba 81 

Cretaceous  formations 81 

Marine  sei  ics  of  the  Upper  Missouri 81 

In. the  South  Saskatchewan  basin 82 

Along  the  Manitoba  escarpment 83 

The  brackish-  and  fresh-water  Laramie  formation 84 

The  wesoern  plains  a  lacustrine  and  land  area  since  the  early  part  of  the  Laramie 

epoch 85 

Fort  Pierre  shales  west  of  Lake  Agassiz 86 

Southwestern  Minnesota  and  the  Coteau  des  Prairies 86 

Along  the  Sheyenne  River 91 

In  the  escarpment  and  plateau  of  Pembina  Mountain 93 

In  western  Manitoba  and  Assiniboia 97 

Former  extent  of  Cretaceous  beds  eastward  on  the  area  of  Lake  Agassiz 100 


CONTENTS.  VU 

Chapter  III. — Geologic  formations  underlying  the  drift — Continued.  Pase. 

Sources  of  the  Cretaceous  deposits 101 

Denudation  of  tbe  Cretaceous  area 102 

Erosion  of  the  plains  to  a  haselevel 102 

Later  erosion  of  the  trough  of  Lake  Agassiz 104 

Chapter  IV. — The  Glacial  period  and  its  drift  deposits 108 

Review  of  the  Glacial  period  in  North  America 108 

The  continental  ice-sheet 110 

Boundaries 110 

Area  and  thickness 112 

Laurentide  and  Cordilleran  centers  of  outflow 119 

Junction  of  the  Laurentide  and  Cordilleran  drift 120 

Comparison  with  the  present  ice-sheet  of  Greenland 123 

Recession  of  the  ice-sheet 126 

Latest  glaciation  far  north 128 

Glacial  currents  within  the  basin  of  Lake  Agassiz 129 

Table  of  courses  of  glacial  striaj 129 

Converging  lobes  of  the  ice-sheet  in  Minnesota  and  Manitoba 129 

Transportation  of  bowlders 130 

Drift  deposits  on  the  lacustrine  area  and  the  adjoining  region 132 

Derivation  of  the  drift  from  preglacial  residuary  detritus  and  from  glacial  erosion.  132 

Thickness  of  the  drift 133 

Till  or  bowlder-clay 134 

Bowlders  and  gravel  from  Archean  and  Paleozoic  formations 136 

Northeastern  limit  of  limestone  drift 137 

Localities  of  very  abundant  and  large  bowlders 137 

Terminal  moraines 139 

Earlier  moraines  formed  before  the  beginning  of  Lake  Agassiz 141 

Sixth  or  Waconia  moraine 142 

Moraines  con  tern  poranous  with  Lake  Agassiz 146 

Seventh  or  Dovre  moraine 147 

Eighth  or  Fergus  Falls  moraine 158 

Ninth  or  Leaf  Hills  moraine 163 

Tenth  or  Itasca  moraine 173 

Eleventh  or  Mesabi  moraine 177 

Modified  or  assorted  drift 179 

Belt  of  modified  drift  between  St.  Paul  and  Winnijieg 181 

Birds  Hill  and  other  eskers  in  Manitoba 183 

Proportion  of  modified  drift  supplied  to  the  deltas  of  Lake  Agassiz 189 

Influence  of  adjoining  lakes  or  the  sea  ou  the  deposition  of  the  drift 190 

Chapter  V. — History  op  Lake  Agassiz 192 

Two  classes  of  Pleistocene  lakes 192 

Lakes  Bonneville,  Lahontan,  and  others  iu  the  Great  Basin 192 

Lake  Agassiz  and  other  glacial  lakes 1 94 

Evidences  of  glacial  lakes 195 

Outlets 195 

Erodedclifts  198 


viii  CONTENTS. 

Chaptkk  v. — HiSTOHY  OF  Lake  Agassiz — Coutiuued.  Page. 

Evidences  of  glacial  lakes — Continued. 

Beaches 199 

Deltas 200 

Lacustrine  sediments 201 

Principal  glacial  lakes  of  the  northern  United  States  and  of  Canada 202 

New  England,  Quebec,  the  eastern  provinces,  the  Northeast  Territory,  and  Labrador. .  202 

Basins  of  the  Laurentian  lakes  and  of  Hudson  Bay 203 

Basins  of  the  Saskatchewan  and  the  Red  River  of  the  North 205 

British  Columbia,  Athabasca,  and  the  Northwest  Territory 206 

Extension  of  Lake  Agassiz  with  tlie  departure  of  the  ice-sheet 208 

Stages  of  growth  shown  by  moraines 210 

Reduction  to  the  present  great  lakes  of  Manitoba 216 

Successive  shore-lines  of  Lake  Agassiz 221 

Dependence  of  the  lake  levels  on  the  erosion  and  changes  of  outlets 222 

Progress  of  erosion  by  the  River  Warren 222 

Later  outlets  northeastward 226 

Dependence  of  lake  levels  on  epeirogenic  elevation 227 

Depression  of  the  continent  shown  by  coastal  submergence 229 

Depression  and  rcelevation  of  the  basin  of  Lake  Agassiz  shown  by  differentially 

uplifted  beaches 230 

Improbable  hypothesis  of  an  outlet  from  Lake  Agassiz  to  the  Mackenzie  River 231 

Probable  hypothesis  of  the  discharge  from  the  northeastward  outlets  being  tributary 

successively  to  the  Mississippi  and  Hudson  rivers 232 

Division  of  the  ice-sheet  into  parts  east  and  west  of  Hudson  Bay 233 

Amount  of  differential  elevation  between  Lake  Traverse  and  Gladstone 234 

Alternate  stages  of  elevation  and  rest 235 

Later  and  greater  inclination  of  beaches  along  the  base  of  Riding  and  Duck  moun- 
tains    235 

Review  of  the  epeirogenic  uplifting 236 

Molluscan  fauna  of  Lake  Agassiz 237 

Measurements  of  time  since  the  Glacial  period 238 

Short  duration  of  Lake  Agassiz 240 

Comparison  with  postglacial  lakes 240 

Comparison  with  Lakes  Bonneville  and  Lahontan 241 

Brevity  of  time  required  for  the  formation  of  terminal  moraines 242 

Alternative  interpretations,  by  T.  C.  Chamberlin 244 

Volume  of  water  received  and  discharged  by  Lake  Agassiz 252 

Fluvial  dejjosits  in  the  Red  River  Valley 253 

Associated  glacial  lakes 254 

The  Laurentian  lakes 255 

Lake  Minnesota 264 

Lake  Dakota 266 

LakeSouris 267 

Lake  Saskatchewan 272 

Glacial  lakes  of  the  Peace  and  Athabasca  basins 274 


CONTENTS.  IX 

Page. 

Chapteu  VI.— Beaches  and  deltas  op  the  Herman  stages 276 

The  upper  or  Herman  beaches  and  deltas  in  Minnesota 278 

From  Lake  Traverse  east  to  Herman "'" 

From  Herman  north  to  the  Red  River.: 28- 

From  the  Red  River  north  to  Muskoda 284 

Delta  of  the  Buffalo  River 290 

From  Muskoda  north  to  the  Sand  Hill  River 292 

Delta  of  the  Sand  Hill  River 298 

Vicinity  of  Maple  Lake -'"" 

Eastward  to  Red  Lake  and  the  Big  Fork  of  Rainy  River 303 

Beltrami  Island ^04 

The  upper  or  Herman  beaches  and  deltas  in  North  Dakota 306 

From  Lake  Traverse  northwest  to  Milnor 306 

From  Milnor  north  to  Sheldon 312 

Delta  of  the  Sheyenne  River 315 

From  Sheldon  north  to  the  Northern  Pacific  Railroad 317 

From  the  Northern  Pacific  Railroad  north  to  Galesburg 322 

From  Galesburg  north  to  Larimore 326 

Delta  of  the  Elk  Valley 333 

Shore  west  of  the  Elk  and  Golden  valleys 337 

Beaches  and  islands  east  of  the  Elk  and  Golden  valleys 345 

From  Gardar  north  to  the  Tongue  River 354 

Delta  of  the  Pembina  River 357 

The  upper  or  Herman  beaches  and  deltas  in  Manitoba 363 

From  the  international  boundary  to  the  vicinity  of  Neepawa 363 

Delta  of  the  Assiniboine  River 370 

Chapter  VII. — Lower  beaches  with  southward  outflow 382 

Beaches  of  the  Norcross  stages 383 

From  Lake  Traverse  to  Norcross  and  Maple  Lake,  Minnesota 383 

Through  North  Dakota,  from  Lake  Traverse  to  the  international  boundary 388 

Western  Norcross  shores  in  Manitoba 393 

Beaches  of  the  Tiutah  stages 396 

Eastern  Tiutah  shores,  from  Lake  Traverse  to  Tintah  and  northward  in  Minnesota 396 

Western  Tintah  shores  in  North  Dakota 402 

Western  Tintah  shores  in  Manitoba 404 

Beaches  of  the  Campbell  stages 407 

From  Lake  Traverse  and  Campbell  north  to  the  Tamarack  River,  in  Minnesota 408 

Campbell  shores  in  North  Dakota 414 

Campbell  shores  in  western  Manitoba 422 

Beaches  of  the  McCauley  ville  stages 427 

Eastern  McCauley  ville  shores  in  Minnesota 428 

Western  McCauleyville  shores  in  North  Dakota 434 

Western  McCauleyville  shores  in  Manitoba 439 

Chapter  VIII.— Beaches  formed  when  Lake  Agassiz  outflowed  northeastward 443 

Beaches  of  the  Blanchard  stages 445 

TheHillsboro  beach 449 


X  CONTENTS. 

Chapter  VIII.— Beaches  formed  when  Lake  Agassiz  outflowed  northeastward— Cont'd .  Page. 

Beaches  of  the  Emerado  stages 454 

Beaches  of  the  Ojata  stages 459 

The  Gladstooe  beach 4g2 

The  Burnside  beach 4g5 

The  Ossowa  beach 4(5g 

The  Stonewall  beach 4Yq 

Beaches  of  the  Ni verville  stages 47j 

Chapter  IX.— Changes  in  the  levels  of  the  beaches 474 

Northward  ascent  of  the  western  shore-lines 474 

Eastward  ascent  of  the  former  lake  levels 4g3 

Rate  of  ascent  greatest  toward  the  north-northeast 485 

Changes  of  levels  nearly  completed  during  the  existence  of  Lake  Agassiz 486 

Causes  of  the  changes  of  levels 4g7 

Gravitation  toward  the  ice-sheet 488 

Changes  in  the  temperature  of  the  earth's  crust 491 

Epeirogenic  movements  apparently  dependent  on  glaciation 492 

Discussion  of  the  relationship  of  the  earth's  crust  to  the  interior 493 

History  of  the  doctrine  of  crust  deformation  by  the  ice- sheet 497 

Tardiness  in  the  beginning  of  the  changes  of  levels  of  the  Lake  Agassiz  basin 498 

Pauses  in  the  crustal  uplift  recorded  by  the  series  of  beaches 499 

Changes  in  levels  of  the  beaches  only  a  partial  measure  of  the  ice  weight 500 

Review  of  Pleistocene  oscillations  of  land  andsea 501 

Preglacial  elevation  of  North  America  shown  by  fjords  and  submarine  river  valleys 501 

Late  Glacial  or  Champlain  submergence  shown  by  the  fossiliferous  marine  beds  over- 
lying the  till 505 

Reelevation  closely  following  the  departure  of  the  ice-sheet 507 

Oscillations  associated  with  glaciation  in  other  countries 509 

Pleistocene  oscillations  independent  of  glaciation  512 

Effects  of  ice  accumulation  on  the  sea-level 515 

Probable  relationship  of  epeirogenic  movements  throughout  the  world  to  glaciation 516 

Epeirogenic  movements  independent  of  glaciation  often  combined  with  others  due  to 

the  ice  weight  and  to  its  removal 520 

Uplift  of  the  basin  of  Lake  Agassiz  apparently  attributable  wholly  to  the  departure  of  the 

ice-sheet 521 

Chapter  X.— Artesian  and  common  wells  op  the  Red  River  Valley 523 

Sources  of  the  artesian  waters 505 

Freshwater  from  porous  beds  of  the  drift  sheet 526 

Saline  and  alkaline  water  from  the  Dakota  sandstone 527 

Relationship  to  the  artesian  wells  of  Devils  Lake  and  the  James  River  Valley 528 

Relationship  to   artesian  wells  at  Tower  City  and  Grafton,  N.  Dak.,  Humboldt, 

Minn.,  and  Rosenfeld,  Manitoba 535 

Analyses  of  waters  from  wells,  streams,  and  lakes  in  the  Red  River  Valley  and  the  adjoining 

region 53g 

Use  of  artesian  water  for  irrigation 545 


CONTENTS.  XI 

Chapter  X. — Artesian  and  common  wells  of  the  Reo  River  Valley — Continued.  Pago. 

Notes  of  artesian  anil  common  wells 548 

Wells  on  the  area  of  Lake  Agassiz  in  Minnesota 550 

Traverse  County 550 

Wilkin  County 551 

Clay  County 555 

Norman  County 557 

Polk  County 559 

Marshall  County 562 

Kittson  County 564 

Wells  ou  the  area  of  Lake  Agassiz  in  North  Dakota 565 

Richland  County 565 

Cass  County 567 

Traill  County 570 

Grand  Forks  County 573 

Walsli  County 574 

Pembina  County 575 

Wells  on  the  area  of  Lake  Agassiz  in  Manitoba .576 

Chapter  XI. — Agricultural  and  material  resources  of  the  area  op  Lake  Aga.ssiz...  582 

Variety  and  distribution  of  the  soils 583 

Climatic  couditions 592 

Rainfall  and  snowfall .592 

Fluctuations  of  lakes  and  streams 594 

Temperature ri9S 

Winds 600 

Flora  of  the  basin  of  the  Red  River  of  the  North 601 

Forest  trees  and  shrubs 603 

Causes  of  limitation  of  the  forest 604 

Prairie  grasses  and  flowers 606 

Development  of  agriculture 610 

Wheat  and  other  cereals 615 

Hay,  potatoes,  flax,  and  other  crops 621 

Stock  raising  and  dairying 624 

Geologic  resources 625 

Gold 625 

Building  stone 626 

Lime 626 

Bricks 627 

Salt 628 

Lignite 629 

Natural  gas 631 

Water  power  and  manufactures 631 

Appendix  A. — Courses  of  glacial  stri.e 633 

Appendix  B. — Notes  op  aboriginal  earthworks  within   and   near  the   area   of  Lake 

Agassiz 643 

Index 647 


ILLUSTRATIONS. 


Page. 

Plate    I.  Browns  Valley,  the  outlet  of  Lake  Agassiz  by  the  River  Warren (Frontispiece.) 

II.  Map  showing  the  relatioushiji  of  Lake  Agassiz  to  tlie  drift-bearing  area  of  North 

America  and  to  Lakes  Bonneville  and  Lahontan 1 

III.  Map  showing  the  areas  of  Lake  Agassiz  and  of  the  ujjper  Laurentian  lakes 10 

IV.  Town  of  Browns  Valley,  Minn 16 

V.  Lake  Traverse 18 

VI.  Upper  Herman  beach  of  Lake  Agassiz 26 

VII.  The  Lightning's  Nest  (dunes  of  the  Sheyenne  delta) 28 

Vin.  The  Leaf  Hills 34 

IX.  Map  with  altitudes  of  Lake  Agassiz  and  adjoining  country 36 

X.  Map  with  altitudes  of  the  southern  portion  of  Lake  Agassiz,  explored  with  leveling 

in  Minnesota,  North  Dakota,  and  Manitoba. 40 

XI.  Map  of  Rainy  Lake  and  the  Lake  of  the  Woods 48 

XII.  Map  of  Red  Lake  and  its  vicinity 50 

XIII.  Map  of  drainage  systems  on  the  area  of  Lake  Agassiz  and  adjoining  country ,52 

XIV.  Map  of  the  rock  formations  underlying  the  drift  on  the  area  of  Lake  Agassiz 65 

XV.  Sections  of  wells  at  Humboldt,  Minn.,  Grafton,  N.  D.ik.,  and  Rosenfeld  and  Morden, 

Manitoba 74 

XVI.  Map  of  the  glaciated  area  of  North  America 110 

XVII.  Map  of  the  drift  deposits  on  the  southern  portion  of  the  basin  of  Lake  Agassiz 132 

XVIII.  Map  of  Devils  and  Stump  lakes 170 

XIX.  Map  showing  the  extent  of  Lake  Agassiz  at  the  times  of  formation  of  the  Fergus 

Falls  and  Leaf  Hills  moraines 212 

XX.  Map  showing  the  extent  of  Lake  Agassiz  at  the  times  of  formation  of  the  Itasca  and 

Mesabi  moraines 214 

XXI.  Map  of  the  Glacial  Lake  Souris 268 

XXII,  Map  of  the  southern  portion  of  Lake  Agassiz,  explored  with  leveling  in  Minnesota, 

North  Dakota,  and  Manitoba,  showing  the  location  of  Plates  XXIII-XXXII 270 

XXIII.  Map  of  Lakes  Traverse  and  Big  Stone,  and  the   shores  of  Lake  Agassiz   near  its 

mouth 280 

XXIV.  Map  of  the  eastern  shores  of  Lake  Agassiz  from  Campbell  north  to  Barnesville  and  its 

vicinity 282 

XXV.  Map  of  the  eastern  beaches  and  deltas  of  Lake  Agassiz  from  Muskoda  north  to  the 

Sand  Hill  River 2S)0 

XXVI.  Map  of  the  eastern  shores  of  Lake  Agassiz,  in  the  vicinity  of  Maple  Lake  and  north- 
ward   298 

XXVII.  Map  showing  the  greater  part  of  the  Sheyenne  delta  of  Lake  Agassiz  and  contiguous 

beaches 316 

xm 


Xiv  ILLUSTRATIONS. 

Page. 
Plate  XXVIII.  Map  of  the  western  shores  of  Lake  Agassiz   from  the  vicinity  of  Wheatland 

north  to  Portland  and  May ville 322 

XXIX.  Map  of  the  western  shores  of  Lake  Agassiz  and  of  the  Elk  Valley  delta,  in 

Grand  Forks  County  and  parts  of  adjoining  counties 334 

XXX.  Map  of  the  western  shores  of  Lake  Agassiz  and  of  the  Pembina  delta,  from 

Park  River  north  to  the  international  boundary 354 

XXXI.  Map  of  the  western  shores  of  Lake  Agassiz  from  Morden  and  Thornhill  north 

to  the  Assiniboine  River 364 

XXXII.  Map  of  the  western  shores  of  Lake  Agassiz,  in  the  vicinity  of  the  Canadian 

Pacific  Railway  and  north  to  Orange  Ridge 368 

XXXIII.  Map  of  the  delta  of  the  Assiniboine  River 370 

XXXIV.  Map  of  the  southern  portion  of  Lake  Agassiz,  showing  its  extent  in  the  lower 

Campbell  stage 408 

XXXV.  Map  of  the  southern  portion  of  Lake  Agassiz,  showing  its  extent  in  the  lower 

Blanchard  stage 446 

XXXVI.  Map  of  the  southern  portion  of  Lake  Agassiz,  showing  its  extent  in  the  Glad- 
stone stage 462 

XXXVII.  Map  showing  the  distribution  and  depths  of  artesian  wells  in  the  Red  River 

Valley .523 

XXXVIII.  Map  of  the  southern  portion  of  Lake  Agassiz,   showing  areas  of  forest  and 

prairie 604 

Fig.    1.  Order  of  sections  in  townships  of  the  United  States  and  of  Manitoba 11 

2.  Section  across  the  Red  River  Valley  on  the  latitude  of  Breckeuridge  and  Wahpeton. ..  22 

3.  Section  across  the  Red  River  Valley  on  the  latitude  of  Moorhead  and  Fargo 23 

4.  Section  across  the  Red  River  Valley  from  Larimore  and  Grand  Forks  to  Maple  Lake..  23 

5.  Section  across  the  Rod  River  Valley  on  the  international  boundary 24 

6.  Typical  section  across  a  beach  ridge  of  Lake  Agassiz 26 

7.  Eroded  terrace  marking  the  shore  of  Lake  Agassiz 26 

8.  Section  across  the  Coteau  des  Prairies 38 

9.  Map  of  Birds  Hill  and  its  vicinity 184 

10.  Section  of  Birds  Hill 185 

11.  Section  across  the  delta  of  the  Buffalo  River 290 

12.  Section  across  the  delta  of  the  Sand  Hill  River 298 

13.  Section  across  the  delta  of  the  Sheyenne  River 316 

14.  Section  across  the  delta  of  tlie  Elk  Valley 334 

15.  Section  across  the  delta  of  the  Pembina  River 358 

16.  Section  across  the  delta  of  the  Assiniboine  River 373 

17.  Profile  of  the  Campbell  escarpment  in  section  6,  Dundee,  N.  Dak 419 

18.  Profile  of  the  Campbell  escarpment  1  mile  south  of  Mountain,  N.  Dak 420 

19.  Section  across  the  Campl)ell  embankment,  in  sections  20  and  21,  T.  161,  R.  55,  N.  Dak 421 

20.  Profile  across  beaches  at  and  near  Barnesville,  Minn 429 

21.  Section  of  the  Campbell  and  McCauleyville  beaches,  in  sections33  and  34,  Liberty,  Minn.  431 

22.  Profile  across  beaches  on  the  north  line  of  Onstead  and  Godfrey,  Minn.,  west  of  Maple 

Lake 432 

23.  Profile  across  beaches  at  and  near  Wheatland,  N.  Dak 435 


ILLUSTEATIONS.  XV 

Paga 

Fig.  24.  Profile  across  beaches  at  Hunter,  N.  Dak.,  and  westward 435 

25.  Profile  across  beaches  in  the  vicinity  of  Arvilla  and  Larimore,  N.  Dak 436 

26.  Profile  across  beaches  at  lukster,  N.  Dak.,  and  westward 437 

27.  Profile  across  beaches  at  Park  River,  N.  Dak.,  and  westward 437 

28.  Section  on  the  international  boundary,  south  of  ranges  G  and  5,  Manitoba 439 

29.  Section  across  r.inges  6  and  5,  Manitoba,  9  to  10  miles  north  of  the  international  boundary.  440 

30.  Section  on  the  south  side  of  township  15,  ranges  13  and  12,  Manitoba,  between  Arden 

and  Gladstone 441 

31.  Diagram  indicating  the  probable  relationship  of  sources  of  artesian  water  at  Grandin, 

N.  Dak 525 

32.  Section  across  the  Red  River  Valley,  showing  the  water  supply  of  its  fresh  artesian 

wells 527 

33.  Section  from  the  Rooky  Mountains  to  the  Red  River  Valley,  showing  the  water  supply 

of  its  saline  artesian  wells 527 

34.  Section  showing  the  series  of  artesian  wells  from  Devils  Lake  and  Jamestown  south- 

ward to  Yankton  and  Vermillion 532 

35.  Section  showing  the  series  of  artesian  wells  from  Harold  eastward  to  Huron 532 


LETTER   OF   TRANSMITTAL. 


University  of  Chicago, 

Chicago,  III,  March  <S',  1S04. 

Sir  :  1  have  the  honor  to  transmit  herewith,  for  pubhcation  as  a 
monograph  of  the  United  States  Geological  Survey,  the  manuscript  of 
a  report  on  the  Ghicial  Lake  Agassiz,  by  Mr.  Warren  Upham.  I  am 
confident  that  it  will  be  welcomed  by  the  scientific  world  as  a  valuable 
contribution  to  the  literature  of  North  American  glaciology. 
Very  respectfully, 

T.  C  Chamberlin, 

Geologist  in  Charge 

To  the  Director  United  States  Geological  Survey. 

XVll 

MON    XXV II 


PREFACE. 


In  my  work  for  the  Geological  and  Natural  History  Survey  of  Minne- 
sota, from  1879  to  1885,  under  the  direction  of  Prof.  N.  H.  Winchell,  State 
geologist,  the  highest  shore-line  of  Lake  Agassiz  in  that  State  was  mapped 
thi'ough  its  prairie  portion,  extending  about  175  miles  from  Lake  Traverse 
eastward  to  Herman  and  thence  northward  to  Maple  Lake.  During  this 
survey  Mr.  Horace  V.  Winchell  was  my  efficient  assistant  as  rodman  in 
leveling.  The  exploration  showed  that  a  very  large  lake  occupied  the  Red 
River  Valley  in  the  closing  stage  of  the  Glacial  period,  when  the  ice-sheet 
was  being  melted  away  from  this  district.  Terminal  moraines  of  the  ice- 
sheet,  forming-  a  series  of  eleven  in  consecutive  order  from  south  to  north, 
were  also  explored  and  mapped  in  Minnesota;  and  it  was  seen  that  the 
glacial  lake  and  moraines  were  intimately  related  as  records  of  the  recession 
of  the  ice  and  the  transition  from  the  Pleistocene  to  the  Recent  or  present 
geologic  period. 

It  became  evident,  however,  that  a  satisfactory  investigation  of  the 
extent  and  history  of  Lake  Agassiz  must  comprise  both  sides  of  the  Red 
River  Valley.  The  United  States  Geological  Survey  therefore  undertook 
the  more  extended  examination  of  this  lake  area,  which  was  assigned  to 
me,  as  a  member  of  the  Glacial  Division,  vmder  the  direction  of  Prof  T.  C. 
Chamberlin,  for  whose  friendly  counsel  and  constant  interest  in  this  work  I 
have  the  pleasure  of  recording  here  my  great  indebtedness.  Suggestions 
derived  from  the  previous  work  for  this  Survey  by  Mr.  G.  K.  Gilbert  and 
Mr.  I.  C.  Russell  on  other  Pleistocene  lakes  also  aided  me  much  in  both  the 
field  work  and  the  study  for  preparing-  this  report. 

Again,  when  the  shore-lines  of  Lake  Agassiz  had  been  mapped  through 
North  Dakota  from  Lake  Traverse  to  the  international  boundary,  it  was 
found  that  a  comprehensive  monograph  of  this  subject  could  not  be  pre- 
sented while  the  exploration  was  restricted  by  a  political  limit.     Hence  it 


XX  PREFACE. 

was  generously  arranged  by  Director  J.  W.  Powell,  of  this  Survey,  and 
Director  A.  R.  C.  Selwyn,  of  the  Geological  and  Natural  History  Survey 
of  Canada,  that  my  work  of  mapping  the  Lake  Agassiz  shores,  with 
determination  of  their  heights  by  leveling,  should  be  continued  tlu-ougli 
the  prairie  region  of  southwestern  Manitoba,  which  was  done  in  the  sum- 
mer of  1887,  the  termination  of  my  survey  being  near  the  southern  end  of 
Riding  Mountain.  Important  observations  of  the  part  of  Lake  Agassiz 
adjoining  the  international  boundary  had  been  previously  made  by  Dr. 
George  M.  Dawson;  arid  during  1887  and  subsequent  years  Mr.  J.  B. 
Tyrrell,  of  the  Canadian  Geological  Survey,  has  added  much  to  the 
explored  extent  of  the  shores  of  this  glacial  lake,  tracing  them  northward 
along  the  east  side  of  the  Riding  and  Duck  mountains,  and  noting  them  in 
isolated  localities  farther  north  to  the  Saskatchewan  River.  My  work  in 
Manitoba  being  thus  supplemented,  this  monograph  is  enabled  to  include 
under  its  descriptions  and  discussion  a  continuous  extent  of  nearly  700 
miles  of  the  ancient  lake  l)order. 

The  field  work  on  Lake  Agassiz  for  the  United  States  Geological 
Survey  occupied  four  summers;  and  during  three  of  these,  in  1885  and 
the  two  following  years,  I  had  the  very  satisfactory  assistance  of  Mr. 
Robert  H.  Young  as  rodman.  The  fourth  summer  of  exploration,  in  1889, 
included  no  leveling,  and  was  chiefly  devoted  to  tracing  the  course  of 
terminal  moraines  adjacent  to  the  area  of  Lake  Agassiz.  With  two  sum- 
mers which  I  had  spent  in  explorati(in  of  this  lake  while  engaged  on  the 
Minnesota  Geological  Survey,  the  work  here  reported  comprises  the  field 
observations  of  six  years. 

Study,  writing,  and  preparation  of  maps  and  illustrations  for  this 
report  and  three  preliminary  ofiicial  publications  relating  to  Lake  Agassiz, 
which  are  noticed  in  Chapter  I,  have  required  considerably  more  time  than 
was  used  in  the  collection  of  field  notes.  For  so  full  opportunity  to  give 
to  this  subject  long-continued  investigation  and  to  present  it  in  this  volume, 
my  grateful  thanks  are  due  and  are  hereby  respectfully  tendered  to  the 
Director  and  to  the  Geologist  in  Charge  of  the  glacial  investigations  of  this 
Survey.  W.  U. 


ABSTRACT  OF  VOLUME. 


Chapter  I:  Introduction. — Lake  Agassiz  occupied  the  ba.sin  of  the  Red  Kiver  of  the  North  and  of 
Lake  Winnipeg.  Its  northern  barrier  was  the  retreating  ice-sheet  of  the  Glacial  period.  That 
a  great  lake  had  existeil  here  was  recognized  by  Keating  in  1823,  iind  later  by  Owen,  Palliser, 
Hind,  Dawson,  Warren,  and  N.  H.  Winchell. 

It  was  named  in  1879  to  commemorate  Louis  Agassiz,  who  established  the  theory  that  the  drift 
was  due  to  glaciation.  Its  southward  outlet  was  named  the  River  W.arren  in  188.3.  The  work 
here  rejiortod  comprises  explorations  performed  for  the  geological  surveys  of  Minnesota,  the 
United  States,  and  Canada.  Previous  reports  and  papers  relating  to  Lake  Agassiz  anrl  its 
dependence  on  the  waning  ice-sheet  are  noted. 

Chapteb  II:  Topography  of  the  isasin  op  Lake  Agassiz. — The  bed  of  this  lake  is  the  Hat  Red 
River  Valley  plain.  Its  channel  of  outlet  by  the  River  Warren  is  now  occupied  by  lakes  Traverse 
and  Big  Stone  and  the  Minnesota  River.  The  shore-lines  of  Lake  Agassiz  are  commonly  marked 
by  beach  ridges  of  gravel  and  sand  a  few  feet  high;  loss  frequently  by  an  eroded  escarpment 
from  10  to  30  feet  high.  Several  large  deltas  were  formed  contemporaneously  with  the  highest 
shore-line.  East  of  Lake  Agassiz  is  a  somewhat  higher  wooded  country,  on  which  are  the  Giants 
and  Mesabi  ranges  and  the  morainic  Leaf  Hills.  On  the  west  are  the  Coteau  des  Prairies  and  the 
Manitoba  escarpment,  the  latter  comprising  the  Pembina,  Riding,  and  Duck  mountains  and 
the  Porcupine  and  Pasquia  hills.  Lake  Agassiz  is  now  represented  by  lakes  Winnipeg,  Mani- 
toba, and  Winnipegosis ;  while  Rainy  Lake,  the  Lake  of  the  Woods,  and  Red  Lake  lie  within 
its  southeastern  boundary.  Its  basin  is  drained  by  the  Rainy,  Winnipeg,  Red,  Assiniboine,  and 
Saskatchewan  rivers,  and  others  of  smaller  size.  For  some  time,  also.  Lake  Agassiz  probably 
received  streams  outflowing  from  glacial  lakes  in  the  basins  of  the  Peace  and  Athabasca  rivers. 
The  area  of  Lake  Agassiz  was  approximately  110,000  sijuare  miles,  and  the  country  tributary  to 
it  was  350,000  to  500,000  square  miles.  The  length  of  the  lake  was  nearly  700  miles;  its  maxi- 
mum width  in  Manitoba  was  probably  more  than  250  miles;  and  its  maximum  depth,  during  its 
earliest  and  highest  stage,  was  about  700  feet  above  the  present  level  of  Lake  Winnipeg. 

Chapter  III :  Geologic  formations  underlying  the  drift. — The  bed  rocks  of  this  lacustrine  area 
comprise,  in  their  order  from  east  to  west,  Archean,  Lower  and  Upper  Silurian,  Devonian,  and 
Cretaceous  formations.  Sections  of  the  Paleozoic  rocks  are  known  by  borings  for  artesian  wells 
at  Humboldt,  Minn.,  Grafton,  N.  Dak.,  and  Rosenfeld  and  Mordon,  Manitoba.  Cretaceous  strata 
extend  from  Lake  Agassiz  westward  across  the  plains  to  the  Rocky  Mountains.  During  the 
Tertiary  era  these  strata  had  been  greatly  denuded,  being  generally  worn  down  to  an  almost  flat 
expanse.  The  vertical  amount  of  the  erosion  was  thousands  of  feet  at  the  west  and  hundreds  of 
feet  at  the  east,  as  shown  by  mountains  and  hills  that  were  spared.  Later  erosion,  during  an 
epeirogenic  uplift  closing  the  Tertiary  and  beginning  the  Quaternary  era,  removed  the  eastern 
part  of  the  Cretaceous  beds,  and  thus  formed  the  broad  trough  of  the  Red  River  Valley  and  of  the 
Manitoba  lake  region,  which  was  the  liasin  of  Lake  Agassiz. 

XXI 


XXII  ABSTEACT  OF  VOLUME. 

Chapter  IV :  The  Glacial  period  and  its  drift  deposits. — TJio  continental  ice-sheet  attained  an 
area  of  about  4,000,000  square  miles,  and  had  a  maximum  thickness,  in  its  central  portion,  of 
probably  1  to  2  miles.  It  extended  from  the  Atlantic  to  the  Pacific  and  from  the  northern  United 
States  to  the  Arctic  Sea,  probably  enveloping  the  Rocky  Mountains  in  the  region  of  the  Peace 
River  and  northward.  The  closing  stage  of  this  glaciation  was  the  time  of  existence  of  Lake 
Agassiz.  On  the  greater  part  of  the  lacustrine  area  the  drift  is  from  100  to  300  feet  thick,  con- 
sisting chiefly  of  till  or  bowlder-clay.  A  series  of  twelve  terminal  moraines  is  found  in  proceeding 
from  south  to  north  and  northeast  in  Minnesota  and  North  Dakota.  The  last  sis  of  those, 
named  the  Dovre,  Fergus  Falls,  Leaf  Hills,  Itasca,  Mesabi,  and  Vermilion  moraines,  were  contem- 
poraneous with  Lake  Agassiz,  besides  probably  others  to  be  traced  farther  north.  Birds  Hill, 
near  Winnipeg,  a  remarkable  esker,  indicates  that  much  drift  was  contained  in  the  lower  part 
of  the  ice-sheet.  The  deltas  of  Lake  Agassiz  were  formed  chiefly  of  modified  drift,  brought  by 
streams  from  the  receding  ice.  Very  little  transportation  of  bowlders  and  other  drift  was 
effected  by  icebergs  or  floes  on  this  lake. 

Chapter  V:  History  op  Lake  Agassiz. — The  records  of  glacial  lakes  are  their  outlets  across  present 
lines  of  watershed ;  eroded  clilfs,  beach  ridges,  and  deltas  at  the  levels  of  the  former  outlets ;  and 
lacustrine  sediments  in  the  basin  inclosed  by  the  old  shores.  Lake  Agassiz  grew  from  south  to 
north  as  fast  as  the  ice-sheet  receded,  forming  its  series  of  moraines.  The  outlet  by  the  River 
Warren  was  eroded  to  a  depth  of  about  90  feet.  Afterwards  lower  outlets  were  opened  toward 
the  northeast.  Probably  the  early  northeastward  outflow  passed  along  the  ice  border  and 
through  the  upper  Laurentian  lakes  to  the  Mississippi,  then  to  the  Hudson  River,  and  later  to 
the  much  enlarged  Gulf  of  St.  Lawrence.  Finally  the  outflow  was  tributary  to  Hudson  Bay 
when  the  ice  had  melted  so  far  as  to  admit  the  sea  to  that  basin.  With  the  uncovering  of  the 
course  of  the  Nelson  River,  Lake  Agassiz  ceased  to  be  held  by  the  ice  barrier,  and  became  Lake 
Winnipeg.  Epeirogenic  uplifting  of  the  area  of  Lake  Agassiz,  increasing  in  vertical  extent  from 
south  to  north,  gave  to  its  beaches  a  northward  ascent,  and  caused  the  several  shores  of  its  south- 
ern part  to  become  double  or  multiple  as  they  are  traced  northward.  The  molluscan  fauna  of 
Lake  Agassiz,  so  far  as  it  has  been  discovered,  consists  of  five  fresh- water  species.  The  amount 
of  the  shore  erosion  of  Lake  Agassiz  and  the  volume  of  its  beaches,  compared  with  the  post- 
glacial erosion  and  beach  deposits  of  the  present  Great  Lakes,  have  a  ratio  approximately  as 
one  to  ten.  The  duration  of  postglacial  time  is  believed  to  have  been  from  seven  to  ten  thousand 
years;  of  Lake  Agassiz,  probably  not  more  than  one  thousand  years. 

Chapter  VI:  Bkaciies  and  deltas  of  the  Herman  stages. — These  shore  deposits  are  described 
in  detail.  The  earliest  and  highest  beach,  named  from  Herman,  Minn.,  has  been  mapped,  with 
determination  of  its  height  by  leveling,  through  an  extent  of  about  17.t  miles  in  Minnesota,  from 
Lake  Traverse  east  to  Herman,  and  thence  north  to  Maple  Lake.  In  140  miles,  from  soiitli  to 
north,  this  shore-line  ascends  from  1,0.50  feet  to  1,170  feet,  approximately,  above  the  sea.  Neat 
Maple  Lake  four  lower  beaches,  successively  about  8, 15,  30,  and  45  feet  below  the  highest,  were 
also  formed  daring  the  time  of  accumulation  of  the  single  Herman  beach  at  the  south ;  and  on  the 
west  side  of  the  lake  in  Manitoba  the  Herman  series  of  beaches  is  increased  to  seven.  In  North 
Dakota  the  uppermost  Herman  shore  has  a  northward  ascent  of  about  180  feet  in  the  distance 
of  224  miles  from  Lake  Traverse  to  the  international  boundary,  where  its  height  is  1,230  feet 
jibove  the  sea.  At  the  latitude  of  Gladstone,  iii  Manitoba,  84  miles  farther  north,  the  altitude  of 
1,315  feet  is  attained  by  the  second  of  the  Herman  shores,  which  is  the  highest  one  extending  so 
far.  Six  noteworthy  deltas  were  brought  into  Lake  Agassiz,  contemporaneously  with  the  for- 
mation of  the  Herman  beaches,  by  streams  which  were  exceptionally  supplied  with  much  modi- 
fied drift  by  the  melting  ice-sheet.     These  are  the  Buff.alo  River  and  Sand  Hill  River  deltas  in 


ABSTRACT  OP  VOLUME.  XXIII 

Minnesota,  the  Sheyenne,  Elk  Valley,  and  Pembina  deltas  in  North  Dakota,  and  the  very  large 
delta  of  the  Assiniboiue  in  Manitoba. 

Chapter  VII:  Lower  beaches  with  southward  outflow.— Below  the  Herman  shoio  the  south- 
ern part  of  Lake  Agassiz  has  four  shore-lines,  which  receive  names  from  Norcross,  Tintah, 
Campbell,  and  McCauleyvilla,  in  Minnesota.  Portions  of  these  shores  have  been  traced  with 
leveling  and  are  hero  described.  In  the  northern  part  of  the  area  of  my  exploration  the  Nor- 
cross and  Tintah  beaches  are  double,  and  the  Campbell  and  McCauleyville  beaches  are  each 
represented  by  three.  With  the  seven  Herman  shores  recorded  in  Manitoba,  Lake  Agassiz  had 
thus  at  the  north  seventeen  stages  marked  by  successive  beaches  during  its  time  of  southward 
discharge  by  the  Eiver  Warren.  The  upper  Norcross  shore  rises  from  about  1,030  feet  above 
the  sea  at  Lake  Traverse  to  1,215  feet  on  the  latitude  of  Gladstone.  In  the  same  distance  the 
upper  Tintah  shore  rises  from  1,01.5  to  1,150  feet;  the  upper  Campbell  shore,  from  990  to  1,080 
feet;  and  the  upper  and  lower  McCauleyville  shores,  respectively,  from  970  to  1,035  feet,  and 
from  960  to  1,012  feet,  approximately,  above  the  present  sea-level. 

Chapter  VIII:  Beaches  formed  when  Lake  Agassiz  outflowed  northbastwabd.— Fourteen 
stages  of  Lake  Agassiz  are  shown  by  beaches  that  were  formed  after  the  lake  had  fallen  below 
its  southern  outlet.  These  comprise,  in  descending  order,  three  successive  Blauchard  beaches, 
passing  near  Blanchard,  N.  Dak. ;  the  Hillsboro  beach,  and  two  Emerado  and  two  Ojata  beaches, 
named  likewise  from  towns  in  North  Dakota ;  and  the  Gladstone,  Burnside,  Ossowa,  Stonewall, 
and  Niverville  beaches,  the  last  being  double  northward,  named  from  places  in  Manitoba.  These 
shore-lines  are  as  definitely  marked  by  beach  ridges,  and  occasionally  by  low  eroded  escarp- 
ments, as  the  series  belonging  to  the  time  of  the  Eiver  Warren.  Their  northward  ascent  is 
gradually  diminished,  until  in  the  latest-formed  Niverville  beach  it  is  only  about  20  feet  in 
the  distance  of  more  than  200  miles  from  near  Winnipeg  and  the  southern  part  of  Lake  Win- 
nipeg northward  to  the  mouth  of  the  Saskatchewan. 

Chapter  IX:  Changes  in  the  levels  of  the  beaches. — The  rate  of  northward  ascent  of  the 
originally  level  highest  beach,  within  the  area  of  my  leveling,  varies  from  about  6  inches  per 
mile  near  its  southern  end  to  about  1  foot  per  mile  along  the  greater  part  of  its  extent  to  south- 
ern Manitoba.  On  the  east  side  of  the  Red  River  Valley  the  old  shores  are  higher  than  on  its 
west  side,  the  rate  of  ascent  from  west  to  east  being  about  half  as  much  as  from  south  to  north. 
The  direction  of  maximum  ascent  of  the  planes  of  the  former  lake  levels  is  therefore  toward 
the  north-northeast.  Farther  north  several  beaches  of  the  series  mapped  by  Tyrrell  along  the 
bases  of  the  Riding  and  Duck  mountains  have  a  northward  rise  of  2  to  3  feet  per  mile.  These 
changes  of  level  were  in  progress  and  were  nearly  completed  during  the  existence  of  Lake 
Agassiz,  as  is  shown  by  the  gradual  diminution  in  the  northward  ascent  of  the  successive  lower 
beaches,  until  the  latest  and  lowest  differs  only  very  slightly  from  perfect  horizontality.  Grav- 
itation of  Lake  Agassiz  toward  the  ice-sheet  accounts  for  a  small  part  of  the  present  inclination 
of  the  beaches.  Changes  in  the  temperature  of  the  earth's  crust  due  to  the  Glacial  period  and 
its  termination  produced  a  still  smaller  effect,  but  this  tended  to  give  the  opposite  slope,  or  a 
descent  toward  the  north.  Upward  epeirogenio  movements,  resulting  from  the  unburdening  of 
the  land  by  the  departure  of  the  ice-sheet,  were  the  chief  element  in  the  causes  of  the  differen- 
tial changes  in  the  height  of  this  basin.  Flow  of  the  plastic  inner  part  of  the  earth's  mass, 
restoring  isostasy,  uplifted  first  the  southern  half  of  the  area  of  Lake  Agassiz,  from  Lake  Trav- 
erse to  Gladstone ;  next  it  raised  the  northern  half  of  the  lake  area,  while  the  region  at  the  south 
was  almost  at  rest;  and  finally,  during  the  Recent  epoch,  afterthe  whole  basin  of  Lake  Agassiz 
was  passed  by  this  wave-like  permanent  uplift,  it  has  been  elevating  the  basin  of  Hudson  Bay, 
where  the  movement  still  continues.     Pleistocene  oscillations  of  the  land  in  many  other  parts 


XXIV  ABSTRACT  OF  VOLUME. 

of  the  world  have  been  independent  of  glaciation,  or  these  have  heen  combined  with  movements 
due  to  the  accumulatiou  of  ice-sheets  and  to  their  removal ;  but  the  upliftiug  of  the  basins  of 
Lake  Agassiz  and  Hudson  Bay  is  apparently  attributable  vrhoily  to  the  departure  of  the  ice- 
sheet. 

Chaptkr  X:  Artesian  and  common  wells  of  the  Red  River  Valley.— Hundreds  of  artesian 
wells,  from  40  to  300  feet  deep,  have  been  obtained  in  the  drift  formations  of  the  Red  River  Valley 
plain,  the  axial  lowest  part  of  the  Lake  Agassiz  basin.  South  of  Crookston  and  Blanchard 
they  yield  fresh  water;  but  northward,  to  the  border  of  Manitoba,  their  water  is  usually  saline 
and  alkaline.  The  fresh  water  is  derived  from  rainfall  on  the  higher  land  adjoining  this  valley. 
The  saline  matter  is  brought  mostly  by  water  flowing  through  the  Dakota  sandstone  and  issuing 
into  the  drift  of  the  Red  River  Valley  upon  tracts  where  this  sandstone  is  the  next  underlying 
formation.  The  saline  and  alkaline  wells  in  the  drift  of  this  district  are  thus  supplied,  like  the 
deeper  artesian  wells  penetrating  the  Cretaceous  strata  at  Devils  Lake  and  in  the  James  River 
Valley,  from  rainfall  on  the  flanks  of  the  Black  Hills  and  Rocky  Mountains.  Analyses  and 
experience  show  that  the  saline  and  alkaline  water  is  not  suitable  for  use  in  irrigation.  Sections 
of  many  artesian  and  common  wells  on  the  area  of  Lake  Agassiz  are  reported,  with  notes  of  the 
characters  of  their  water  supply. 

Chapter  XI :  Agricultural  and  materlal  resources  of  the  area  of  Lake  Agassiz.— The  fertility 
of  the  soil  and  the  climatic  conditions  of  the  prairie  portion  of  this  area  make  agriculture  its 
leading  industry  and  source  of  wealth.  Previous  to  its  occupation  by  the  present  farming 
population  the  rich  pasturage  and  countless  herds  of  buffaloes  betokened  the  value  of  the  land 
for  the  cultivation  of  grain  and  for  stock-raising.  The  annual  wheat  product  of  the  six  counties 
in  Minnesota  and  sis  in  North  Dakota  lying  mainly  within  the  Red  River  Valley  is  about  46,000,000 
bushels,  or  on  an  average  285  bushels  for  each  of  the  161,049  people  enumerated  by  the  census  of 
1890  in  these  counties.  Other  crops  which  receive  considerable  attention  are  oats,  barley,  hay, 
potatoes,  and  flax.  The  tendency  is  toward  diversified  farming,  with  stock-raising  and  dairying. 
Magnesian  limestones,  which  outcrop  near  Winnipeg,  are  used  for  building  and  the  manufacture 
of  lime.  Clay  of  the  best  quality  for  brickmaking  is  found  along  all  the  Red  River  Valley,  and 
this  business  is  carried  on  in  many  places.  The  brines  and  natural  gas  occasionally  supplied  by 
wells,  and  the  lignite  occurring  in  very  thin  layers  in  Cretaceous  formations  of  this  region,  and 
thence  sparsely  distributed  in  fragments  through  the  drift,  are  not  of  economic  importance. 
Many  streams  within  the  area  of  Lake  Agassiz,  especially  in  the  northeastern  wooded  country, 
have  valuable  water  powers,  which  are  beginning  to  be  utilized  for  mills  and  manufactures. 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH 


MAP  SUOMTNG  THK  H  ELA  TIOXSllIP  OF  LAKK  AGASSI/  TO  TIIK  DRIFT-BKAKIXG  AREA 
OF  NORTH  .VAn-:KK"AANJ)  TOL.VliKS  BOX.N'EMLLE  AND  LAHOXTAX. 

Scale  .  about  550 miles  to  aii  inch  . 
Areas  covered  bvLandlcr  during  aie(^iaUTnnryJ!;ra  |  j      (Juatei-iwrvLaltes  Bonne\nllf  aiij  l.ahomaii  arid  theOlacial  LakeAgSLSSiz 


THE  GLACIAL  LAKE  AGASSIZ. 


By  Warren  Upham. 


CHAPTER    I. 

INTRODUCTION. 

BASIIf    OF    THE    KED    RIVER.  OF    THE    NORTH    AND    OF    EAKE 

WINNIPEG. 

The  glacial  lake  which  is  the  theme  of  this  volume  extended  along  the 
Red  River  Valley  and  covered  the  lake  country  of  Manitoba.  Its  situation 
in  the  center  of  the  continent,  and  its  geographic  relation  to  the  cWft- 
covered  area  and  to  lakes  Bonneville  and  Lahontan,  are  displayed  in 
Plate  II.  Lake  Agassiz  was  the  largest  of  the  many  Pleistocene  lakes  of 
North  America,  some  of  which  were  formed  by  the  barrier  of  the  ice-sheet 
during  its  recession,  while  others  were  produced  by  increased  rainfall  in  the 
great  western  arid  region  that  has  no  di'ainage  to  the  sea. 

Only  a  comparatively  small  fraction — about  one-fifth — of  the  area  of 
Lake  Agassiz  lies  within  the  United  States,  but  this  includes  the  greater 
portion  of  its  exactly  explored  shore-lines.  A  very  large  part  of  its  area 
in  Canada,  besides  a  considerable  tract  within  its  limits  in  northern  Minne- 
sota, is  covered  by  forest,  which  makes  it  impracticable  to  trace  there  the 
beach  ridges  and  deltas,  low  escarpments  of  erosion,  and  other  evidences  of 
this  lake  so  continuously  as  has  been  done  through  the  prairie  region. 
This  great  expanse  of  prairie,  upon  which  the  shore-lines  have  been  accu- 
rately and  continuously  mapped,  comprises  the  Red  River  Valley  and 
adjoining  higher  land,  and  reaches  north  to  the  southern  ends  of  lakes 
Winnipeg  and  Manitoba  and  of  Riding  Mountain.  Farther  north  tracts  of 
prairie,  divided  by  woodlands  and  thickets,  continue  inten-uptedly  along 
the  eastern  base  of  Riding  and  Duck  mountains,  permitting  considerable 
parts  of  the  ancient  shores  to  be  traced  in  that  district. 
MON   XXV 1 


2  THE  GLACIAL  LAKE  AGASSIZ 

As  this  report  necessarily  treats  of  the  topographic  features  of  the 
basin  of  the  Red  River  and  Lake  Winnipeg,  it  has  seemed  desirable  to 
devote  a  chapter  to  the  rock  formations  which  underlie  the  glacial  di'ift  and 
the  old  lake  bed,  with  discussion  of  the  preglacial  erosion  that  gave  the 
general  outlines  of  the  Red  River  Valley  plain  and  of  the  Manitoba  escarp- 
ment bounding  it  on  the  west.  Though  this  part  is  presented  somewhat 
briefly,  it  is  hoped  that  the  reader  will  be  able  to  obtain  in  it  a  compre- 
hensive review  of  the  entire  geologic  history  of  this  area,  and  of  its  uplift 
and  sculpturing  to  the  form  of  a  basin,  previous  to  the  Ice  age  and  the  time 
of  Lake  Agassiz. 

The  economic  geology  of  this  basin  has  received  a  large  share  of 
attention  during  the  progress  of  the  field  work  and  in  the  present  volume. 
Owing  to  the  structure  of  the  drift  deposits  and  of  the  underlying  rocks, 
many  artesian  wells  have  been  obtained  in  the  Red  River  Valley,  descrip- 
tive notes  of  which  are  given,  with  analyses  of  their  waters,  and  an  expla- 
nation of  the  sources,  in  part  near  and  probably  in  part  hundreds  of  miles 
distant,  from  which  the  waters  and  their  dissolved  mineral  matter  are 
derived.  No  commercially  valuable  deposits  of  ores,  coal,  natural  gas,  or 
salt  can  be  reported,  but  the  northern  part  of  the  Red  River  Valley,  in 
Manitoba,  has  magnesian  limestone  of  excellent  quality  for  building  pur- 
poses and  for  the  manufacture  of  lime,  and  the  whole  valley  has  plentiful 
beds  of  clay,  unsurpassed  for  brickmaking.  The  chief  resources  of  this 
extensive  prairie  region  of  Lake  Agassiz,  however,  are  found  in  its  very 
fertile  soil  and  favorable  climate  for  agriculture,  and  especially  for  wheat 
raising. 

THE    GLACIAL    LAKE    AGASSIZ. 

During  the  closing  part  of  the  latest  completed  division  of  geologic 
time  a  vast  lake  stretched  from  the  southern  end  of  the  Red  River  Valley 
north  to  the  Saskatchewan  and  Nelson  rivers.  The  late  date  of  its  exist- 
ence is  known  by  the  position  of  its  shore-lines  and  deltas,  which  lie  upon 
the  glacial  drift  and  have  nearly  as  perfect  outlines  as  those  of  the  present 
shores  of  the  Manitoba  and  Laurentian  lakes  or  of  the  ocean.  This  ancient 
lake,  several  times  larger  than  Superior — indeed,  exceeding  the  aggregate 
area  of  the  five  great  lakes  tiibutary  to  the  St.  Lawrence — washed  the  east 


EELATIONSHIP  TO  THE  ICE-SHEET.  3 

and  west  borders  of  the  Red  River  Valley  and  the  base  of  the  Riding  and 
Duck  mountains.  Its  surface  during  storms  was  raised  into  waves  which 
formed  well-defined  beach  ridges  of  gravel  and  sand,  and  these  are  found 
at  many  successive  levels,  showing  that  the  area  and  depth  of  the  lake 
were  gradually  diminished.  Before  these  deserted  shores  and  the  inclosed 
lacustrine  area  were  examined  in  the  field  work  for  this  report,  their  char- 
acter had  been  observed  and  was  generally  attributed  to  lake  action  by  the 
immigrant  farmers,  who  in  many  instances  selected  the  beach  ridges  as  the 
sites  of  their  dwellings. 

Intervals  of  small  vertical  amount  divide  the  consecutive  beaches, 
from  the  highest  to  the  lowest.  Through  the  earher  and  probably  greater 
part  of  the  duration  of  the  lake  it  outflowed  southward  by  the  way  of 
Lake  Traverse,  Browns  Valley,  Big  Stone  Lake,  and  the  Minnesota  River 
to  the  Mississippi.  Seventeen  shore-lines  on  the  northern  portion  of  the 
lake  area  were  formed  contemporaneously  with  this  southern  outlet.  Later 
the  lake  was  further  reduced  tlu'ough  stages  shown  by  fourteen  shore-lines, 
while  it  outflowed  by  successively  lower  avenues  of  discharge  northeast- 
ward. Finally  it  was  reduced  to  lakes  Winnipeg,  Manitoba,  and  Winni- 
pegosis,  which  are  the  lineal  descendants  and  representatives  of  Lake 
Agassiz. 

RELATIOlSrSHIP  TO  THE    ICE-SHEET. 

The  conditions  to  which  Lake  Agassiz  owed  its  existence,  however, 
were  very  unlike  those  of  the  present  time.  It  could  not  have  been  held  in 
a  landlocked  basin,  for  there  has  been  no  subsidence  of  the  country  between 
this  area  and  Hudson  Bay  since  the  Glacial  period.  Instead,  the  area  of 
Lake  Agassiz  and  all  the  region  northeastward  to  Hudson  Bay  and  Strait 
have  experienced  a  gradual  uplift  during  the  time  of  the  departure  of  the 
ice-sheet  and  subsequently.  As  shown  by  the  northwardly  ascending 
shore-lines  of  this  lake  and  by  fossiliferous  marine  beds  overlying  the 
glacial  drift  on  the  lower  country  adjoining  Hudson  Bay  and  along  the 
Ottawa  and  St.  Lawrence  rivers,  the  vertical  extent  of  this  uplift  was 
greatest  toward  the  north  and  east.  It  was  little  at  Lake  Traverse,  but 
amounted  to  400  or  500  feet  in  Manitoba,  and  was  approximately  500  to 
600  feet  on  the  southwest  side  of  Hudson  and  James  bays  and  upon  all 


4  THE  GLACIAL  LAKE  AGASSIZ. 

the  interior  portion  of  the  continent  thence  to  Ottawa  and  Montreal.  It  is 
evident,  therefore,  that  no  barrier  of  land  held  the  lake  which  covered  the 
Red  River  Valley  and  a  large  part  of  Manitoba.  Bnt  a  southward  outlet 
is  found  through  which  the  lake  flowed  to  the  Mississippi,  and  no  marine 
fossils  have  been  detected  in  or  above  the  drift  upon  this  area,  from  which 
reasons  it  is  certain  that  these  ancient  shore-lines  were  not  produced  by 
subsidence  of  the  land  beneath  the  sea-level,  followed  by  reelevation. 
While  the  beaches  and  deltas  here  described  are  thus  known  to  be 
lacustrine,  fossils  have  been  discovered  in  them  at  only  two  localities,  these 
being  shells  of  five  species  of  fresh-water  mollusks,  occurring  in  beaches 
that  belong  to  the  middle  and  later  part  of  the  lake's  history. 

From  all  these  features  of  the  former  lake,  when  they  are  considered 
in  their  relationship  to  the  Glacial  period  and  its  drift  deposits,  we  are  led  to 
the  conclusion  that  the  northern  barrier  by  which  its  water  was  held  in  was 
a  waning  ice-sheet.  The  glacial  striae,  till,  terminal  moraines,  and  other  drift 
formations  prove  that  the  northern  half  of  our  continent  has  been  enveloped 
by  a  continuous  mantle  of  ice  stretching  from  the  eastern  shores  of  New 
England  and  Canada  west  to  the  Rocky  Mountains  and  the  Pacific,  and 
from  the  northern  part  of  the  United  States  to  the  Arctic  Sea.  When  this 
ice-sheet  was  melted  away,  its  border  gradually  withdrew  from  south  to 
north,  and  hydrographic  basins  descending  northward  were  temporarily 
occupied  by  glacial  lakes,  held  by  the  ice  barrier  until  its  continued 
retreat  allowed  free  drainage  of  these  basins  in  the  direction  of  their  slopes. 
This  explanation  fully  accounts  for  the  presence  of  Lake  Agassiz  in  the 
basin  of  the  Red  River  and  of  Lake  Winnipeg  during  the  recession  of  the 
ice-sheet,  for  the  scantiness  of  its  fauna,  and  for  the  northward  ascent  of  its 
originally  level  shores,  since  the  earth's  crust  had  been  depressed  by  the  ice 
burden,  and  was  uplifted,  in  the  preservation  of  its  equilibrium,  when  the 
ice-sheet  departed. 

The  work  of  Gilbert,  Chamberlin,  Leverett,  and  others  in  the  basins 
of  \he  Laurentian  lakes  has  proved  that  their  formerly  much  higher  levels, 
marked  by  shore-lines  similar  to  those  of  Lake  Agassiz,  were  contempora- 
neous with  the  departure  of  the  ice-sheet  and  the  formation  of  its  recessional 
moraines.     Records  of  many  other  smaller  glacial  lakes  have  been  observed 


NAME  IN  MEMORY  OF  LOUIS  AGASSIZ.  5 

ujjon  all  the  glaciated  area  of  our  continent  from  New  England  to  British 
Columbia.  The  ice-sheet  of  northwestern  Europe  also  formed  such  lakes 
during  its  final  melting.  Some  of  these  lakes,  pent  up  in  valleys  2,000  to 
3,000  feet  above  the  sea,  between  the  eastern  side  of  the  Scandinavian 
Mountains  and  the  remnant  of  the  ice  still  covering  eastern  Sweden, 
attained  lengths  of  about  100  miles  and  depths  of  about  1,000  feet.^  In 
Scotland,  likewise,  the  famous  Parallel  Roads  of  Glen  Roy  are  shown  to  be 
the  shores  of  successive  stages  of  a  lake  held  by  the  barrier  of  the  waning 
Scottish  ice-sheet.^  The  positions  of  the  European  glacial  lakes,  as  of 
those  in  North  America,  were  determined  by  the  areas  of  greatest  thickness 
of  the  ice  and  the  manner  of  its  recession. 

When  the  Glacial  period  in  North  America  was  ending,  as  soon  as  the 
border  of  the  ice  had  receded  beyond  the  watershed  dividing  the  basins  of 
the  Minnesota  and  Red  rivers,  it  is  evident  that  a  lake,  fed  by  the  glacial 
melting,  stood  at  the  foot  of  the  ice  fields  and  extended  northward  as  they 
withdi-ew  along  the  Red  River  Valley  to  Lake  Winnipeg,  filling  this  Aalley 
to  the  height  of  the  lowest  point  over  which  an  outlet  could  be  found. 
Until  the  ice  barrier  was  so  far  melted  upon  the  area  between  Lake 
Winnipeg  and  Hudson  Bay  that  this  glacial  lake  began  to  be  discharged 
northeastward,  its  outlet  was  along  the  present  course  of  the  Minnesota 
River.  Because  of  its  relation  to  the  retreating  continental  ice-sheet,  this 
lake  has  been  named  in  memory  of  Prof  Louis  Agassiz,  the  first  prominent 
advocate  of  the  theory  that  the  drift  was  produced  hj  land  ice.^  Within 
the  past  fifteen  years  the  truth  of  this  explanation  of  the  drift  has  been 
demonstrated  by  the  recognition  and  detailed  study  of  the  morainic 
deposits  that  were  accumulated  along  the  boundary  of  the  ice-sheet  from 

'A.  H.  Hansen,  in  Nature,  Vol.  XXXIII,  1886,  pp.  268,  269,  365. 

'T.  F.  Jamieson,  in  Quart.  ,Jour.  Geol.  Soc,  Vol.  XLVIII,  1892,  pp.  5-28. 

=  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Eighth  Anuual  Report,  for  the  year  1879,  pp.  84,  85. 
(Jean  Louis  Eodolpbe  Agassiz  was  horn  in  Motier,  Switzerland,  Way  28,  1807,  and  died  in  Cambridge, 
Mass.,  December  14,  1873.  His  observations  of  the  Swiss  glaciers  and  his  principal  writings  concerning 
them  and  the  glacial  origin  of  the  drift  were  during  the  years  1836  to  1846.  In  the  autuiuu  of  1846 
Agassiz  came  to  the  United  States,  and  tlie  remainder  of  his  life  was  mostly  spent  here  in  zoological 
researches  and  in  teaching  in  Harvard  College,  where  be  founded  the  Museum  of  Comjiarative 
Zoology.  The  interests  of  science  in  this  country  were  inestimably  advanced  by  bis  great  iulhieuce 
as  a  teacher  and  by  his  extensive  writings  in  zoology,  in  which  and  the  care  of  the  museum  his  work 
has  been  ably  continued  by  his  son,  Alexander  Agassiz.  See  the  biography,  Louis  Agassiz:  His  Life 
and  Correspondence,  edited  by  Elizabeth  Cary  Agassiz.    2  vols.     1885.) 


6  THE  GLACIAL  LAKE  AGASSIZ. 

southern  New  Englaud  and  Long  Island  to  North  Dakota  and  Assiniboia. 
The  characters  of  other  drift  deposits  point  with  equal  certainty  to  a  vast 
sheet  of  land  ice  as  their  cause;  and  the  explanation  accounts  for  this  lake 
in  the  Red  River  Valley,  for  similar  lakes  that  were  tributary  to  it  from  the 
basins  of  the  Som-is  and  South  Saskatchewan  rivers,  and  for  the  contempo- 
raneous higher  levels  of  the  great  lakes  now  discharged  by  the  River  St. 
Lawrence. 

EARLY   OBSERVATIONS   OF   LAKE   AGASSIZ. 

The  evidences  of  the  former  existence  of  a  great  lake  in  the  Red 
River  Valley  were  observed  in  1823  by  Keating,  the  geologist  of  the  first 
scientific  expedition  to  this  district,^  in  1848  by  Owen,^  in  1857  by  Palhser,^ 
in  1858  by  Hind,*  and  in  1873  by  Dr.  G.  M.  Dawson.'  Each  of  these 
geologists  explored  considerable  tracts  of  the  lacustrine  area,  recognizing  its 
limits  in  a  few  places ;  and  Hind  especially  described  and  mapped  portions 
of  the  lower  beach  ridges.  Dr.  Dawson's  work  was  in  connection  with  the 
British  North  American  Boundary  Commission,  and  includes  detailed  notes 
of  the  part  of  this  area  lying  between  the  Lake  of  the  "Woods  and  the 
Pembina  Mountain.  Several  references  to  these  authors  and  quotations 
£i-om  their  reports  are  presented  in  later  pages  of  this  volume. 

The  excavation  of  the  valley  occupied  by  Lakes  Traverse  and  Big 
Stone  and  the  Minnesota  River  was  first  explained  in  1868  by  Gen.  G.  K. 
Warren,  who  attributed  it  to  the  outflow  from  this  ancient  lake.  He  made 
a  careful  sm-vey  of  this  valley,  and  his  maps  and  descriptions,  with  the 
accompanying  discussion  of  geologic  questions,  are  most  valuable  contri- 
butions to  science.^     After   his    death,  in    commemoration  of   this  work, 

1  Narrative  of  an  Expedition  to  the  Source  of  St.  Peters  River,  Lake  Winnepeek,  Lake  of  the 
Woods,  etc.,  performed  in  the  year  1823,  *  *  *  under  the  command  of  Stephen  H.  Long,  U.  S. 
Topographical  Engineer.     London,  1825.     Vol.  II,  p.  3. 

-  Report  of  a  Geological  Survey  of  Wisconsin,  Iowa,  and  Minnesota.     Philadelphia,  1852.     P.  178. 

3 Journals,  detailed  reports,  etc.,  presented  to  Parliament,  19th  May,  1863,  p.  41. 

••  Report  of  the  Assiniboiue  and  Saskatchewan  Exploring  Expedition.  Toronto,  1859.  Pp.39,  40, 
167,  168. 

^  Report  on  the  Geology  and  Resources  of  the  Region  in  the  Vicinity  of  the  Forty-ninth  Parallel, 
from  the  Lake  of  the  Woods  to  the  Rocky  Mountains.     Montreal,  1875.     P.  248. 

6  "On  certain  physical  features  of  the  Upper  Mississippi  River,"  American  Naturalist,  Vol.  II, 
pp.  497-502,  November,  1868.  Annual  Report  of  the  Chief  of  Engineers,  United  States  Army,  for  1868, 
pp.  307-314.  "An  essay  concerning  important  physical  features  exhibited  in  the  valley  of  the  Min- 
nesota River,  .ind  upon  their  signification,"  with  maps;  Report  of  Chief  of  Engineers,  1875.  "Valley 
of  the  Minnesota  River  and  of  the  Mississippi  River  to  the  junction  of  the  Ohio;  its  origin  consid- 


WORK  EEPOETED  IN  THIS  MONOGEAPH.  7 

the  glacial  river  that  was  the  outlet  of  Lake  Agassiz  was  named  River 
Warren/ 

That  this  lake  existed  because  of  the  ban-ier  of  the  receding  ice-sheet 
was  first  pointed  out  in  1872  by  Prof  N.  H.  Winchell.^ 

WORK  REPORTED  IN    THIS    MONOGRAPH. 

The  part  of  the  area  of  Lake  Agassiz  which  lies  in  Minnesota,  so  far 
as  it  is  prairie,  was  explored  by  the  writer  in  1879  and  1881,  under  the 
direction  of  Prof  N.  H.  Winchell,  State  geologist;  and  in  the  latter  year 
the  highest  or  Herman  beaches  in  that  State,  and  small  parts  of  lower 
shore-lines,  were  carefully  surveyed  and  mapped,  their  heights  being 
determined  by  leveling,  with  the  assistance  of  Horace  V.  Winchell  as 
rodman.  This  work  has  been  reported  in  publications  of  the  Minnesota 
Geological  Survey.^  It  is  also  used  in  this  monograph,  which  comprises  in 
addition,  for  the  part  of  the  lake  area  in  Minnesota,  a  large  amount  of  later 
observations  made  during  my  field  work  for  the  United  States  Geological 
Survey,  pertaining  chiefly  to  the  lower  beaches,  artesian  wells  in  the  Red 
River  Valley,  and  terminal  moraines  upon  the  region  eastward  to  Red  Lake, 
Itcisca  and  Leech  lakes,  and  Brainerd. 

Exploration  of  the  Lake  Agassiz  shore-lines,  deltas,  and  associated 
glacial  and  lacustrine  formations  was  again  entered  upon  by  the  writei', 
for  the  United  States  Geological  Siu-vey,  in  1885,  as  a  part  of  the  woi'k  of 
the  Glacial  Division,  under  the  direction  of  Prof  T.  C.  Chamberlin.  During 
the  years  1885  to  1887,  inclusive,  the  upper  or  Herman  beaches  in  North 
Dakota,  and  extensive  portions  of  the  lower  shores  both  in  North  Dakota 
and  Minnesota,  were  mapped  and  their  altitudes  ascertained  continuously 
by  leveling,  in  which  I  was  assisted  by  Robert  H.  Young.  We  traveled 
mostly  afoot  for  this  surveying,  our  daily  advance  varying  from  3  to  10 

ered;  depth  of  the  bed  rock,"  with  maps;  Report  of  Chief  of  Engineers,  1878,  and  Am.  Jour.  Sci.  (3), 
Vol.  XVI,  pp.  417-431,  December,  1878.     (General  Warren  died  August  8,  1882.) 

'Proc.  A.  A.  A.  S.,  Vol.  XXXII,  for  1883,  pp.  213-231;  also  in  Am.  Jour.  Sci.  (3),  Vol.  XXVII, 
Jan.  and  Feb.,  1884;  and  Geology  of  Minnesota,  Vol.  I,  p.  622. 

-Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  First  Annual  Report,  for  1872,  p.  63 ;  and  Sixth  Annual 
Report,  for  1877,  p.  31.  Professor  Winchell  also  explained  in  like  manner  the  formerly  higher  levels 
of  the  Laurentian  lakes.  Popular  Science  Monthly,  June  and  July,  1873 ;  and  the  same  view  is  stated 
by  Prof.  J.  S.  Newberry  in  the  Report  of  the  Geological  Survey  of  Ohio,  Vol.  II,  1874,  pp.  6, 8,  and  51. 

^Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Eighth  Annual  Report,  for  1879,  pp.  84-87;  Eleventh 
Annual  Report,  for  1882,  pp.  137-153,  with  maj);  and  Final  Report,  Vols.  I  and  II. 


8  THE  GLACIAL  LAKE  AGASSIZ. 

miles.     A  preliminary  report  of  part  of  these  observations  was  published 
in  1887.^ 

By  cooperation  of  the  geological  surveys  of  the  United  States  and 
Canada,  a  portion  of  my  field  work  in  1887  was  devoted  to  the  examination 
of  the  northward  extension  of  the  beaches  of  Lake  Agassiz  in  Manitoba. 
Traveling  with  horse  and  wagon,  and  assisted  by  Mr.  Young,  a  somewhat 
detailed  exploration  of  this  lacustrine  area  was  continued  about  a  hundi-ed 
miles  north  from  the  international  boundary,  the  most  northern  points 
reached  being  Shoal  Lake,  between  Lakes  Winnipeg  and  Manitoba,  and 
Orange  Ridge  post-office,  near  the  southeast  end  of  Riding  Mountain.  The 
mainlv  wooded  character  of  the  country  farther  north  makes  continuous 
leveling  and  tracing  the  beaches  of  this  lake  impracticable;  and  the  same 
condition  limited  my  examination  on  the  east  to  a  naiTOw  belt  adjoining 
the  Red  River.  The  western  border  of  this  portion  of  Lake  Agassiz  is 
formed  bv  the  Pembina  Mountain,  the  Tiger  Hills,  the  Brandon  Hills,  and 
Riding  Mountain ;  and  the  mouth  of  the  Assiniboine  was  at  Brandon  during 
the  highest  stage  of  the  lake.  In  this  direction  my  observations  were 
extended  west  of  the  shore-line  of  Lake  Agassiz  to  include  the  vicinit}^  of 
the  Assiniboine  and  the  Canadian  Pacific  Railway  to  Griswold,  the  coru'se 
of  the  Souris  River  below  Plum  Creek,  Langs  Valley,  a  glacial  water- 
"ui'se  extending  from  the  elbow  of  the  Souris  southeast  to  Pelican  Lake 
and  the  Pembina  River,  and  the  lower  course  of  that  river,  by  Avhieh  a 
large  delta  was  deposited  in  the  west  margin  of  Lake  Agassiz  a  few  miles 
south  of  the  international  boundary.  The  breadth  of  the  comitry  thus 
ti'aversed  from  east  to  west  is  about  150  miles.  A  report  of  this  woi'k  has 
been  published  by  the  Canadian  Geological  Survey.' 

For  all  these  surveys  in  the  United  States  and  Manitoba  profiles  of 
the  numerous  railway  lines  crossing  this  district  supplied  reliable  elevations 
above  the  sea-level  at  their  stations;  and  in  manv  instances  they  also  show 
distinctly  their  intersections  of  the  beaches  of  this  lake.  These  elevations 
were  taken  as  the  data  and  reference  points  of  my  leveling,  wliich  was 


'  TJ.  S.  Geol.  Survey  Bulletin,  No.  39.  The  Upper  Beaches  and  Deltas  of  the  Glacial  Late  Agassiz. 
Pp.  84,  -with  map 

-Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Re])ort,  new  series,  Vol.  IV,  for  1888-89,  Part  E, 
Eeport  of  Exploration  of  the  Glacial  Lake  Agassiz  in  Manitoba,  pp.  156,  with  two  maps  and  a  plate 
of  sections. 


DETEEMINATIONS  OF  ALTITUDES.  9 

proved  throughout  its  entire  extent  to  be  accurate  within  close  approxima- 
tion by  its  agreement  with  the  railway  surveys,  the  comparisons  being 
made  at  intervals  varying  from  20  to  40  or  50  miles.  A  very  large  number 
of  railway  profiles,  extending  beyond  the  limits  of  Lake  Agassiz  to  Lakes 
Superior  and  Michigan  and  to  the  Pacific  Ocean,  were  examined  during 
this  work,  and  the  altitudes  of  their  stations,  summits  of  grade,  bridges, 
and  low  and  high  water  of  the  streams  crossed,  were  tabulated  for  con- 
venient reference  and  comparison,  being  uniformly  referred  to  the  sea-level 
at  mean  tide.  This,  auxiliary  part  of  the  investigations  relating  to  Lake 
Agassiz  has  been  separately  published.^  In  the  present  volume  the  alti- 
tudes of  the  railway  stations  are  noted  on  Pis.  XXIII  to  XXXIII,  which 
give  the  detailed  sm'veys  of  the  lake  beaches  and  deltas.  For  the  whole 
area  of  this  glacial  lake,  so  far  as  it  has  been  explored  with  leveling  and 
is  traversed  by  these  railway  surveys,  their  altitudes  are  noted  on  PI.  X. 

Exact  or  close  agreements  of  several  independent  surveys  from  the 
sea  to  this  district,  and  of  the  profiles  of  the  many  intersecting  lines  of 
railway  in  Minnesota,  South  and  North  Dakota,  and  Manitoba,  give  com- 
plete assurance  that  these  heights,  and  those  determined  therefrom  by 
leveling  along  a  thousand  miles  or  more  of  the  shore-lines  of  Lake  Agassiz, 
are  not  only  consistent  together  but  also  absolutely  true  within  limits  of 
error  probably  nowhere  exceeding  5  feet.  Such  exact  detenninations  of 
the  elevations  of  the  beaches  seem  very  important,  because  these  deposits 
which  Avere  formed  along  the  level  shores  of  the  lake  in  its  successive 
stages  are  found  at  the  present  time  to  have  a  gradual  ascent  from  south  to 
north,  amounting,  within  the  portion  of  the  lake  area  surveyed  h\  me,  to 
about  a  foot  per  mile  in  the  highest  and  oldest  beach,  and  gradually 
diminishing-  to  a  quarter  or  even  an  eighth  part  of  this  amount  in  the 
lowest  and  latest  of  the  beaches.  Some  interesting  problems  are  thus 
presented  as  to  the  relationship  of  these  progressive  changes  of  level, 
when  they'  were  produced,  and  their  causes. 

During  the  year  of  my  exploration  in  Manitoba,  and  since  that  time, 
important  observations  of  the  beaches  of  Lake  Agassiz  farther  northward 
along  the  Manitoba  escarpment  and  near  the  mouth  of  the  Saskatchewan 

'  U.  S.  Geol.  Survey,  Bulletin  No.  72.     Altitudes  between  Lake  Superior  and  the  Rocky  Mountains. 
1891.     Pp.  229. 


10  THE  GLACIAL  LAKE  AGASSIZ. 

have  been  made  during  work  for  the  Greological  Survey  of  Canada  by  Mr. 
J.  B.  Tyrrell.^  Notes  of  these  additions  to  our  knowledge  of  the  glacial  lake 
are  included  in  this  monograph,  and  contribute  much  to  the  history  of  the 
differential  uplift  of  the  lake  area.  Mr.  Tyrrell  finds  that  in  northwestern 
Manitoba  the  lower  beaches  formed  during  the  time  of  southward  outflow 
of  Lake  Agassiz  have  been  changed  in  height,  so  that  they  now  ascend  2 
to  3  feet  per  mile  northward.  Their  changes  of  level  are  thus  twice  as 
gi-eat  as  those  of  the  higher  and  earlier  beaches  within  the  area  of  my 
leveling,  and  they  took  place  after  the  uplifting  of  the  more  southern  part 
of  the  lake  area  had  nearly  ceased. 

The  close  relationship  of  Lake  Agassiz  and  the  uphft  of  its  area  with 
the  recession  of  the  ice-sheet  showed  that  this  work  would  not  be  complete 
without  a  special  examination  of  the  terminal  moraines  which  form  con- 
spicuous belts  of  hilly  drift  upon  the  country  both  east  and  west  of  the 
lacustrine  area,  and  whose  courses  in  the  Red  River  Valley  are  commonly 
marked  only  by  a  somewhat  uneven  or  almost  flat  surface  of  till,  with  fre- 
quent or  often  plentiful  bowlders.  Accordingly,  in  1889  several  months 
were  given  to  field  work  in  tracing  these  moraines.  The  region  explored 
in  North  Dakota  extended  from  the  head  of  the  Coteau  des  Prairies,  west 
of  Lake  Traverse,  northward  and  northwestward  to  Devils  Lake,  Turtle 
Mountain,  the  Souris  River,  and  the  Coteau  du  Missouri,  in  the  northwestern 
part  of  this  State.  On  the  other  side  of  Lake  Agassiz  my  field  work  in 
1889  extended  east  to  Lake  Itasca  and  the  upper  part  of  the  Mississippi. 
With  the  account  of  these  observations  given  in  Chapter  IV,  brief  notes 
are  also  supplied  from  my  earlier  reports  relating  to  the  terminal  moraines 
in  Minnesota.^ 

"Wliile  my  explorations  and  studies  of  Lake  Agassiz  have  been  in  prog- 
ress for  the  Minnesota,  United  States,  and  Canadian  Geological  Surveys, 
I  have  presented  portions  of  their  results  in  various  reports  and  papers,  as 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  Ill,  for  1887-88,  Part 
E,  Notes  to  accompany  a  preliminary  map  of  the  Ridmg  and  Duck  mountains  in  northwestern  Mani- 
toba, 16  pages,  with  map.  Other  papers  by  Mr.  Tyrrell,  including  descriptions  of  portions  of  the 
Lake  Agassiz  beaches,  are  "Post- Tertiary  Deposits  of  Manitoba  and  the  adjoining  territories  of  north- 
western Canada,"  Bulletin,  G.  S.  A.,  Vol.  1,  1890,  pp.  395-410,  and  "Pleistocene  of  the  Winnipeg 
Basin,"  Am.  Geologist,  Vol.  VIII,  pp.  19-28,  July,  1891. 

=  Geol.  and  Nat.  Hist.  Survey  of  Minn.,  Eighth  and  Ninth  Annual  Reports,  for  the  years  1879  and 
1880;  and  Final  Report,  Geology  of  Minnesota,  Vol.  I,  1884,  and  Vol.  II,  1888. 


PEELIMINARY  PAPBES. 


11 


enumerated  below  in  their  chronologic  order.^  These  preliminary  reports 
and  discussions  bearing  more  or  less  directly  on  this  subject  have  been 
drawn  from  in  many  places  during  the  preparation  of  the  present  work. 

The  map  given  in  PL  III  shows  the  whole  extent  of  Lake  Agassiz, 
and,  for  comparison  with  it,  the  upper  great  lakes  that  outflow  by  the  St. 
Lawrence.  The  courses  of  glacial  strife  and  terminal  moraines  are  also 
shown,  so  far  as  they  have  been  mapped ;  but  doubtless  numerous  moraines 
in  Canada  remain  to  be  filled  in  by  future  exploration.  It  should  be 
remarked,  however,  that  the  northern  and  northeastern  boundaries  of  this 
glacial  lake  probably  can  never  be  exactly  determined,  and  must  be  laid 
down  in  any  attempt  of  this  kind  by  estimation,  for  they  were  formed  by 
the  receding  ice-sheet  instead  of  a  land  surface  on  which  beaches  would  be 
discoverable. 


6 

5 

4 

3 

2 

f 

31 

32 

33 

34 

35 

36 

7 

S 

9 

10 

II 

IZ 

30 

29 

28 

27 

26 

25 

18 

17 

16 

IS 

14 

13 

13 

20 

21 

22 

23 

24 

19 

20 

21 

22 

Z1 

24 

18 

17 

16 

15 

14 

13 

30 

23 

ze 

27 

26 

25 

7 

8 

9 

10 

11 

12 

31 

32 

33 

34 

35 

36 

6 

5 

_4j 

3 

z 

± 

United  States.  M.-initoba. 

Fig.  1 — Order  of  sections  in  townships. 


Detailed  descriptions  of  the  beaches  and  deltas  occupy  three  chapters 
and  are  illustrated  by  a  series  of  ten  map  plates  (XXIII  to  XXXII),  hav- 

"' Preliminary  report  on  the  geology  of  central  and  western  Minnesota,"  Geol.  and  Nat.  Hist. 
Survey  of  Minn.,  Eighth  An.  Rep.,  for  1879,  pp.  70-125. 

"Lake  Agassiz:  a  chapter  in  glacial  geology,"  Bulletin  of  the  Minnesota  Academy  of  Natural 
Sciences,  Vol.  II,  pp.  290-314,  Jan.,  1882;  also  in  Geol.  and  Nat.  Hist.  Survey  of  Minn.,  Eleventh  An. 
Eep.,  for  1882,  pp.  137-153,  with  map. 

"The  Minnesota  Valley  in  the  Ice  age,"  Proc.  A.  A.  A.  S.,  1883,  Vol.  XXXII,  pp.  213-231;  also  in 
Am.  Jour.  Sci.  (3),  Vol.  XXVII,  pp.  31-42  and  104-111,  Jan.  and  Feb.,  1884. 

Geology  of  Minnesota,  Fiual  Report,  Vol.  I,  1884,  pp.  408,  442,  461,  484,  581,  622. 

"The  upper  beaches  and  deltas  of  the  glacial  Lake  Agassiz,"  Bulletin  No.  39,  U.  S.  Geol.  Survey, 
1887,  pp.  84,  with  map. 

"The  recession  of  the  ice-sheet  in  Minnesota  in  its  relation  to  the  gravel  deposits  overlying  the 
quartz  implements  found  by  Miss  Babbitt  at  Little  Falls,  Minn.,"  Proc.  Boston  Soc.  of  Nat.  Hist., 
Vol.  XXIII,  pp.  436-447,  Dec,  1887. 

Geology  of  Minnesota,  Final  Report,  Vol.  II,  1888,  pp.  134,500,504,517-527,551,656,662,664-7. 

"Glaciation  of  mountains  in  New  England  and  New  York,"  Appalachia,  Vol.  V,  1889,  pp. 
291-312;  also  in  Am.  Geologist,  Vol.  IV,  Sept.  and  Oct.,  1889. 

"Probable  causes  of  glaciation,"  appendix  in  Prof.  G.  F.  Wright's  Ice  Age  in  North  America, 
1889,  pp.  573-595. 

"Report  of  exploration  of  the  Glacial  Lake  Agassiz  in  Manitoba,"  Geol.  and  Nat.  Hist.  Survey 
of  Canada,  Annual  Report,  new  series,  Vol.  IV,  for  1888-89,  Part  E,  1890,  pp.  156,  with  two  maps  and 


12  THE  GLACIAL  LAKE  AGASSIZ. 

ing  the  scale  of  6  miles  to  an  inch.  Section  lines  are  drawn  on  these  maps, 
which  will  enable  the  reader  to  refer  readily  to  the  localities  designated  in 
the  text  by  the  numbers  of  the  section,  township,  and  range.  For  the  con- 
venience of  those  who  may  not  be  acquainted  with  the  unlike  systems 
employed  in  the  United  States  and  in  Manitoba  for  numbering  the  sections 
of  each  township,  fig.  1  is  here  inserted.  Occasional  reference  to  this 
figure,  with  attention  given  to  the  township  and  range  numbers  noted  on 
the  maps,  will  soon  fix  in  one's  memory  the  significance  of  these  terms  of 
the  land  surveys. 

a  plate  of  sections.  (The  division  of  this  report  forming  its  pages  42-56,  entitled  "History  of  Lake 
Agassiz,"'  was  reprinted  in  the  Am.  Geologist,  Vol.  VII,  March  and  April,  1891.) 

"Artesian  wells  in  North  and  South  Dakota,"  Am.  Geologist,  Vol.  VI,  pp.  211-221,  Oct.,  1890. 

"On  the  cause  of  the  Glacial  period,"  Am.  Geologist,  Vol.  VI,  pp.  327-339  and  396,  Dec,  1890. 

"A  review  of  the  Quateruarj' era,  with  special  reference  to  the  deposits  of  flooded  rivers,"  Am. 
Jour.  Sci.  (3),  Vol.  XLI,  pp.  33-52,  .Jan.,  1891. 

"Glacial  lakes  in  Canada,"  Bulletin,  G.  .S.  A.,  Vol.  II,  1891,  pp.  243-276. 

"Altitudes  between  Lake  Superior  aud  the  Rocky  Mouutaius,"  Bulletin  No.  72,  U.  S.  Geol.  Sur- 
vey, 1891,  pp.  229. 

"The  ice-sheet  of  Greenland,"  Am.  Geologist,  Vol.  VIII,  pp.  145-152,  Sept.,  1891. 

"Criteria  of  englaoial  and  subglacial  drift,"  Am.  Geologist.  Vol.  VIII,  pp.  376-385,  Dec,  1891. 

"Inequality  of  distribution  of  the  euglacial  drift,"  Bulletin,  G.  S.  A.,  Vol.  Ill,  1892,  pp.  134-148. 

"Relationship  of  the  glacial  lakes  Warren,  Algonquin,  Iroquois,  and  Hudson-Champlain," Bul- 
letin, G.  S.  A.,  Vol.  Ill,  1892,  pp.  484-487. 

"The  Champlain  submergence,"  Bulletin,  G.  S.  A.,  Vol.  Ill,  pp.  508-511. 

"Conditions  of  accumulation  of  drumlins,"  Am.  Geologist,  Vol.  X,  pp.  339-362,  Dec,  1892. 

"Estimates  of  geologic  time,"  Am.  Jour.  Sci.  (3),  Vol.  XLV,  pp.  209-220,  March,  1893. 

"Comparison  of  Pleistocene  aud  Present  ice-sheets,"  Bulletin,  G.  S.  A.,  Vol.  IV,  1893,  pp.  191-204. 

"Beltrami  Island  of  Lake  Agassiz,"  Am.  Geologist,  Vol.  XI,  pp.  423-425,  June,  1893. 

"Englacial  drift,"  Am.  Geologist,  Vol.  XII,  pp.  36-43,  July,  1893. 

"Epeirogenic  movements  associated  with  glaoiation,"  Am.  Jour.  Sci.  (3),  Vol.  XLVI,  pp.  114-121, 
Aug.,  1893. 

"Evidences  of  the  derivation  of  the  kames,  eskers,  and  moraines  of  the  North  American  ice- 
sheet  chiefly  from  its  euglacial  drift,"  Bulletin,  G.  S.  A.,  Vol.  V,  1894,  pp.  71-86. 

"  The  succession  of  Pleistocene  formations  in  the  Mississippi  and  Nelson  River  basins,"  Bulletin, 
G.  S.  A.,  Vol.  V,  1894,  pp.  87-100. 

"Wave-like  progress  of  an  epeirogenic  uplift,"  Journal  of  Geology,  Vol.  II,  pp.  383-395,  May- 
June,  1894. 

"  Causes  and  conditions  of  glaciation,"  Am.  Geologist,  Vol.  XIV,  pp.  12-20,  July,  1894. 

"  Tertiary  and  early  Quaternary  baseleveling  in  Minnesota,  Manitoba,  and  northwestward,"  Am. 
Geoliigist,  Vol.  XIV,  pp.  235-246,  Oct.,  1894.  (Abstract  in  Bulletin,  G.  S.  A.,  Vol.  VI,  pp.  17-20, 
Nov.,  1894.) 

"Departure  of  the  ice-sheet  from  the  Laurentian  lakes,"  Bulletin,  G.  S.  A.,  Vol.  VI,  pp.  21-27, 
Nov.,  1894. 

"Quaternary  time  divisible  in  three  periods,  the  Lafayette,  Glacial,  and  Recent,"  Am.  Natu- 
ralist, Vol.  XXVII,  pp.  979-988,  Dec,  1894. 

"Preliminary  report  of  field  work  duriug  1893  in  northeastern  Minnesota,  chiefly  relating  to 
the  glacial  drift,"  in  the  Twenty-second  Annual  Report  of  the  Geol.  Survey  of  Minnesota  for  1893 
(pub.  1894),  pp.  18-66,  with  map  and  sections. 

"Late  Glacial  or  Champlain  subsidence  and  reelevatlon  of  the  St.  Lawrence  River  basin,"  Am. 
Jour.  Sci.  (3),  Vol.  XLIX,  pp.  1-18,  with  map,  Jan.,  1895. 


FUETHER  WOEK  EEOOMMENDED.  13 

Many  changes  will  be  brought  by  coming  years  upon  the  areas  thus 
mapped,  in  the  springing  up  of  new  villages,  the  organization  and  naming 
of  townships,  and  the  construction  of  new  lines  and  branches  of  railways. 
It  is  to  be  hoped,  also,  that  local  observers,  as  teachers  in  the  common 
schools  and  in  the  colleges  and  universities  of  Fargo,  Grand  Forks,  Winni- 
peg, and  other  cities,  will  supplement  the  work  herein  described  and 
mapped  by  adding  such  portions  of  the  lower  shore-lines  of  Lake  Agassiz 
as  have  not  yet  been  definitely  traced.  The  sections  of  new  artesian  wells 
should  likewise  be  recorded  and  studied  in  comparison  with  the  notes  of 
wells  here  reported. 


CHAPTER  II. 

TOPOGRAPHY  OF  THE  BASIN  OF  LAKE  AGASSIZ. 

The  area  that  was  covered  by  Lake  Agassiz  occupies  the  geographic 
center  of  the  North  American  continent.  Its  extent  is  approximately  from 
45°  30'  to  55°  of  north  latitude,  and  from  92°  30',  on  the  international 
boundary,  to  106°,  on  the  Saskatchewan  River,  of  Avest  longitude. 

If  we  consider  the  contour  of  the  entire  continent,  it  is  seen  to  include 
on  the  east  and  west  two  mountainous  regions  and  between  them  a  compar- 
atively flat  expanse,  at  the  middle  of  which  Lake  Agassiz  lay.  The  eastern 
mountainous  tract  stretches  from  Labrador  southwestward  to  Alabama, 
culminating  in  the  Laurentide  highlands  north  of  the  River  St.  Lawrence, 
the  White  Mountains  and  the  Adirondacks,  the  Grreen  Mountains  and  the 
Catskills,  and  the  parallel  Appalachian  ranges  farther  southwest.  The 
summits  of  this  mountain  belt  vary  in  elevation  from  a  half  mile  to  one 
mile  and  slightlj^  more  above  the  sea-level.  On  the  west,  a  longer  and 
wider  region  of  mountains,  including  generally  tlu'ee  or  four  lofty  parallel 
ranges,  extends  from  the  northern  and  southern  coasts  of  Alaska  south- 
easterly and  southerly  through  the  Canadian  Northwest  Territory,  British 
Columbia,  the  western  thhd  of  the  United  States,  Mexico,  and  Central 
America,  to  the  Isthmus  of  Panama;  and  beyond  this  it  continues  south  in 
the  great  Andes  range  along  the  entire  western  coast  of  South  America  to 
Cape  Horn.  In  the  United  States  this  Cordilleran  mountain  Ijelt  includes 
the  Rocky  Mountains  and  the  Sierra  Nevada  and  Coast  ranges,  and  its 
highest  summits  are  nearly  3  miles  above  the  sea. 

Lake  Agassiz,  situated  on  the  central  expanse  between  these  moun- 
tainous regions,  was  a  fifth  of  a  mile  above  the  present  sea-level.  Where 
the  slow  northward  ascent  from  the  Gulf  of  Mexico  ceases  at  a  distance  of 
1,100  miles  from  the  Gulf  and  an  elevation  of  about  1,100  feet,  and  is 
succeeded  farther  north  by  a  descending  slope  toward  Hudson  Bay,  the 

14 


OUTLET  BY  THE  ElVEE  WARKEN.  15 

barrier  of  the  receding  ice-sheet  caused  this  glacial  lake  to  till  the  Red 
River  Valley  and  to  reach  northward,  as  the  ice  front  retreated,  over  the 
region  of  Lakes  Winnipeg,  Manitoba,  and  Winnipegosis,  until  the  continued 
melting  of  the  ice  at  last  permitted  it  to  be  drained  by  the  natural  slope  of 
the  land  to  the  northeast,  excepting  its  remnants,  which  form  these  lakes  of 
Manitoba. 

outijEt,  bed,  and  shores  of  lake  agasstz. 

river  warren. 

The  lowest  point  of  the  watershed  dividing  the  great  areas  that  are 
di-ained  respectively  to  Hudson  Bay  and  the  Gulf  of  Mexico  is  between 
Lakes  Traverse  and  Big  Stone,  on  the  boundary  line  of  Minnesota  and 
South  Dakota.  Its  elevation  above  the  ocean  is  975  feet.  Here  an  ancient 
watercom-se,  called  Browns  Valley  (see  the  frontispiece  and  PI.  IV), 
which  was  occupied  by  the  River  Warren,  outflowing  from  Lake  Agassiz, 
is  eroded  in  the  thick  sheet  of  glacial  drift  to  a  depth  of  100  to  125  feet, 
with  a  width  of  about  1^  miles.  The  tops  of  its  inclosing  bluff's  and  the 
general  level  of  the  adjoining  country  of  undulating  or  moderately  rolling- 
till  are  about  1,100  feet  above  the  sea.  Portions  of  this  channel  contain 
the  long  and  narrow  Lakes  Traverse  and  Big  Stone,  the  former  outflowing 
by  the  Bois  des  Sioux  River  and  the  Red  River  of  the  North  to  Lake 
Winnipeg  and  Hudson  Bay,  and  the  latter  by  the  Minnesota  River  to  the 
Mississippi.  But  this  channel  shows  that  subsequent  to  the  deposition  of 
the  di'ift  a  great  river  has  flowed  here  across  what  is  now  one  of  the 
principal  watersheds  of  the  continent. 

The  head  stream  of  the  Minnesota^  River,  from  which  the  State  of 
Minnesota  receives  its  name,  after  flowing  eastward  about  20  miles  from  its 
sources  on  the  Coteau  des  Prairies,  turns  southei'ly  at  Browns  Valley  and 
enters  the  northwest  end  of  Big  Stone  Lake.  Here,  and  in  its  whole 
extent  thence  to  its  mouth,  the  Minnesota  River  occupies  the  channel  of  the 
glacial  River   Warren.      This  valley  or  channel  begins  at   the  northern 

'The  aboriginal  Dakota  name,  meaning  "  water  nearly  clear,  but  slightly  clouded,"  or,  poetically 
translated,  "sky-tinted  water."  (A.  W.  Williamson,  in  Thirteenth  Annual  Report,  Geol.  and  Nat. 
Hist.  Survey  of  Minn.,  for  1884,  p.  109.  E.  D.  Neill,  History  of  Miuuesota,  1858,  p.  xlvii.  Nicollet's 
Report,  1843,  p.  69.) 


16  THE  GLACIAL  LAKE  AGASSIZ. 

part  of  Lake  Traverse,  and  first  extends  southwest  to  the  head  of  this 
lake,  thence  southeast  to  Mankato,  and  next  north  and  northeast  to  the 
Mississippi  at  Fort  Snelhng,  its  length  being  about  250  miles.  Its  width 
varies  from  1  to  4  miles,  and  its  depth  is  from  100  to  225  feet.  The 
country  through  which  it  lies,  as  far  as  Carver,  about  25  miles  above  its 
junction  with  the  Mississippi,  is  a  nearly  level  expanse  of  till,  only, 
modei'ately  undula,ting,  with  no  prominent  hills  or  notable  depressions, 
excepting  this  deep  channel  and  those  formed  by  its  tributary  streams. 
Below  Carver  it  intersects  a  belt  of  terminal  moraine,  composed  of  hilly 
till.  Its  entire  course  is  through  a  region  of  unmodified  drift,  which  has 
no  exposures  of  solid  rock  upon  its  surface. 

Bluff's  in  slopes  from  20  to  40  degrees,  and  rising  100  to  200  feet  to 
the  general  level  of  the  country,  form  the  sides  of  this  trough-like  valley. 
They  have  been  produced  by  the  washing-  away  of  their  base,  leaving  the 
upper  portion  to  fall  down  and  thus  take  its  steep  slopes.  The  river  in 
deepening  its  channel  has  been  constantly  changing  its  course,  so  that  its 
current  has  been  turned  alternately  against  the  opposite  sides  of  its  valley, 
at  some  time  undermining  every  portion  of  them.  In  a  few  places  this 
process  is  still  going  forward,  but  mainly  the  course  of  the  Minnesota 
River  is  in  the  bottom-land.  Comparatively  little  excavation  has  been  done 
by  the  present  river.  As  we  approach  its  source  it  dwindles  to  a  small 
stream  flowing  through  long  lakes,  and  we  finally  pass  to  Lake  Traverse, 
which  empties  northward ;  yet  along  the  upper  Minnesota  and  at  the  divide 
between  this  and  the  Red  River  this  valley  or  channel  and  its  inclosing 
bluff's  are  as  remarkable  as  along  the  lower  part  of  the  Minnesota  River. 
It  is  thus  clearly  shown  to  have  been  the  channel  of  outflow  from  a  lake 
formerly  extending  northward  from  Lake  Traverse. 

The  Minnesota  Valley  in  many  places  cuts  tlu-ough  the  sheet  of  di-ift 
and  reaches  the  underlying  rocks,  which  have  frequent  exposures  along  its 
entire  course  below  Big  Stone  Lake.  This  excavation  shows  that  the 
thickness  of  the  general  drift  sheet  upon  this  part  of  Minnesota  averages 
about  150  feet.  The  contour  of  the  old  rocks  thus  brought  into  view  is 
much  more  uneven  than  that  of  the  drift.  In  the  hundred  miles  from  Big 
Stone  Lake  to  Fort  Ridgely  the  strata  are  Archean  gneisses  and  granites. 


<   s; 
I-    5 

O     fl 


5    5 


I   t; 


THE  MINNESOTA  EIVEE  VALLEY.  17 

which  often  fill  the  entire  valley,  1  to  2  miles  wide,  rising  in  a  profusion  of 
knolls  and  hills  50  to  100  feet  above  the  river.  The  depth  eroded  has  been 
limited  here  by  the  presence  of  these  rocks,  among  which  the  river  flows  in 
a  winding  course,  crossing  them  at  many  places  in  rapids  or  falls. 

From  New  Ulm  to  its  mouth  the  river  is  at  many  places,  bordered  by 
Cretaceous  and  Lower  Silurian  and  Cambrian  rocks,  which  are  nearly 
level  in  stratification.  These  vary  in  height  from  a  few  feet  to  50  or  rarely 
75  or  100  feet  above  the  river.  From  Mankato  to  Ottawa  the  river 
occupies  a  valley  cut  in  Shakopee  limestone  underlain  by  Jordan  sandstone, 
which  form  frequent  bluffs  upon  both  sides,  50  to  75  feet  high.  After 
excavating  the  overlying  125  to  150  feet  of  till,  the  river  here  found  a 
former  valley  eroded  by  preglacial  streams.  Its  bordering  walls  of  rock, 
varying  from  one-fourth  of  a  mile  to  at  least  2  miles  apart,  are  in  many 
portions  of  this  distance  concealed  by  drift,  which  alone  forms  one  or  both 
sides  of  the  valley.  The  next  point  at  which  the  river  is  seen  to  be 
inclosed  by  rock  walls  is  in  its  last  2  miles,  where  it  flows  between  bluffs 
of  Trenton  limestone  underlain  by  St.  Peter  sandstone,  100  feet  high  and 
about  a  mile  apart.  This  also  is  a  preglacial  channel,  its  further  continu- 
ation being  occupied  by  the  Mississippi  River.  The  only  erosion  effected 
here  by  the  Minnesota  River  has  been  to  clear  away  a  part  of  the  drift 
with  which  the  valley  was  filled.  Its  depth  at  some  earlier  time  was  much 
greater  than  now,  ■  as  shown  by  the  salt  well  on  the  bottom-land  of  the 
Minnesota  at  Belle  Plaine,  where  202  feet  of  stratified  gravel,  sand,  and 
clay  were  penetrated  before  reaching  the  rock.^  The  bottom  of  the 
preglacial  channel  there  is  thus  at  least  165  feet  lower  than  the  mouth  of 
the  Minnesota  River. 

The  height  of  Lake  Traverse,^  in  the  range  between  its  lowest  and 
highest  stages,  is  970  to  976  feet  above  the  sea;  the  lowest  point  in  Browns 
Valley  between  this  and  Big  Stone  Lake  is  only  3  feet  above  the  ordinary 
stage  of  Lake  Traverse;    Big  Stone  Lake^  ranges  from  962  to  967  feet 

'Geology  of  Min.,  Vol.  II,  p.  134. 

=  A  ti-iiuslation  of  the  Dakota  iiume  (Williamson,  1.  c,  p.  108).  "The  lake  has  received  its 
present  appellation  from  the  circumstance  that  it  is  in  a  direction  nearly  transverse  to  that  of  the  Big 
Stone  and  Qui  Parle  lakes."    Keating's  Narrative,  Vol.  II,  p.  2. 

■'Translated  from  the  Dakota  (Williamson,  1.  c,  p.  105).  The  name  probably  alludes  to  the 
conspicuous  outcrops  of  granite  found  in  the  Minni'sota  Valley  1  to  3  miles  below  the  foot  of  the  lake. 

MON    XXV 2 


18  THE  GLACIAL  LAKJ}  AGASSIZ. 

above  the  sea,  its  ordinary  stage  being  about  8  feet  below  that  of  Lake 
Traverse ;  and  the  mouth  of  the  Minnesota  River  at  extreme  low  water  is 
688  feet  above  the  sea,  the  descent  from  Big  Stone  Lake  to  the  mouth  of 
the  river  being  274  feet. 

Lakes  Traverse  and  Big  Stone  are  from  1  to  1 J  miles  wide,  mainly 
occupjnng  the  entire  area  between  the  bases  of  the  bluffs,  which  rise  about 
125  feet  above  them.  Lake  Traverse  (PI.  V)  is  15  miles  long;  it  is  mostly 
less  than  10  feet  deep,  and  its  greatest  depth  probably  does  not  reach  20 
feet.  Big  Stone  Lake  is  26  miles  long,  and  its  greatest  depth  is  reported  to 
be  from  15  to  30  feet.  The  portion  of  the  channel  between  these  lakes 
is  widely  known  as  Browns  Valley.  As  we  stand  upon  the  bluffs  here, 
looking  down  on  these  long  and  naiTOw  lakes  in  their  trough-hke  valley, 
which  extends  across  the  5  miles  between  them,  where  the  basins  of 
Hudson  Bay  and  the  Gulf  of  Mexico  are  now  divided,  we  have  nearly  the 
scene  wliich  was  presented  when  the  melting  ice-sheet  of  British  America 
was  pouring  its  floods  along  this  hollow.  Then  the  entire  extent  of  the 
valley  was  doubtless  filled  every  summer  by  a  river  which  covered  all  the 
present  areas  of  flood  plain,  in  many  places  occupying  as  great  width  as 
these  lakes. 

Greneral  WaiTen  observed  that  Lake  Traverse  is  due  to  partial  siltmg 
up  of  the  channel  since  the  outflow  from  the  Red  River  basin  ceased,  the 
Minnesota  River  at  the  south  having  brought  in  sufficient  alluvium  to  form 
a  dam;  wliile  Big  Stone  Lake  is  similarly  referred  to  the  sediment  brought 
into  the  valley  just  below  it  by  the  Whetstone  River.  Fifteen  ixiiles  below 
Big  Stone  Lake  the  Minnesota  River  flows  through  a  marshy  lake  4  miles 
long  and  about  a  mile  wide.  This  may  b6  due  to  the  accumulation  of 
allu^^um  brought  into  the  valley  by  the  Pomme  de  Terre  River,  which 
has  its  mouth  about  2  miles  below.  Twenty-five  miles  from  Big  Stone 
Lake  the  river  enters  Lac  qui  Parle,  ^  which  extends  8  miles,  with  a  width 
varying  from  one-fourth  to  three-fourths  of  a  mile  and  a  maximum  depth 
of  12  feet.  This  lake,  as  Greneral  Warren  suggested,  has  been  formed  by 
a  ban-ier  of  stratified  sand  and  silt  which  the  Lac  qui  Parle  River  has 


'The  French  translation  of  the  Dakota  name,  which  is  of  uncertain  origin  (Williamson,  1.  c, 
p.  106). 


''^m~ 


mm 


3  * 


LAKES  TRAVERSE,  BIG  STONE,  AND  LAC  QUI  PARLE.  19 

thrown  across  the  valley.  He  also  showed  that  Lake  Pepin,  on  the 
Mississippi,  is  dammed  in  the  same  way  by  the  sediment  of  the  Chippewa 
River;  and  that  Lake  St.  Croix  and  the  last  30  miles  of  the  Minnesota 
River  are  similarly  held  as  level  backwater  by  the  recent  deposits  of  the 
Mississippi. 

The  valleys  of  the  Pomme  de  Terre  and  Chippewa  rivers,  75  to  100 
feet  deep  along  most  of  their  com-se  and  one-fonrth  of  a  mile  to  1  mile 
in  width,  were  probably  avenues  of  di-ainage  from  the  melting  ice  fields 
in  their  noilhward  retreat.  Between  these  rivers,  in  the  22  miles  from 
Appleton  to  Montevideo,  the  glacial  floods  at  first  flowed  in  several 
channels,  which  are  excavated  40  to  80  feet  below  the  general  level  of  the 
drift  sheet,  and  vary  from  an  eighth  to  a  half  of  a  mile  in  width.  One  of 
these,  starting  from  the  bend  of  the  Pomme  de  Terre  River,  IJ  miles  east 
of  Appleton,  extends  15  miles  sovitheast  to  the  Chippewa  River,  near  the 
center  of  Tunsburg.  This  old  channel  is  joined  at  Milan  station  by 
another,  which  branches  ofi"  from  the  Minnesota  Valley,  running  4  miles 
east-southeast;  it  is  also  joined  at  the  northwest  corner  of  Tunsburg  by  a 
very  notable  channel  which  extends  eastward  from  the  middle  of  Lac  qui 
Parle.  The  latter  channel,  and  its  continuation  in  the  old  Pomme  de  Ten'e 
Valley  to  the  Chippewa  River,  are  excavated  nearly  as  deep  as  the  channel 
occupied  by  the  Minnesota  River.  Its  west  portion  holds  a  marsh  generally 
known  as  the  "Big  Slough."  Lac  qui  Parle  would  have  to  be  raised  only 
a  few  feet  to  tm-n  it  tln-ough  this  deserted  valley.  The  only  other  localities 
where  we  have  proof  that  the  floods  of  the  River  Warren  at  first  ran  in 
several  channels  are  7  and  10  miles  below  Big  Stone  Lake,  where  isolated 
remnants  of  the  general  sheet  of  till  occur  south  of  Odessa  station  and 
again  3  miles  southeast.  Each  of  these  former  islands  is  about  a  mile  long, 
and  rises  75  feet  above  the  suiTounding  lowland,  or  nearly  as  high  as  the 
bluffs  inclosing  the  valley,  which  here  measures  4  miles  across,  having  a 
greater  width  than  at  any  other  point. 

THE    RED    RIVER    VALLEY. 

Proceeding  northward  to  the  area  of  Lake  Agassiz,  whose  outflow 
formed  this  channel,  the  observer  finds  that  the  broad  Avatercourse,  with 
its  bluffs  and  the  adjoining  highland  on  each  side,  ends  a  few  miles  north 


20  THE  GLACIAL  LAKE  AGASSIZ. 

of  Lake  Traverse.  There  the  country  sinks  gradually  to  a  level  not  much 
above  the  small  Bois  des  Sioux  River,  which  is  the  outlet  of  Lake  Traverse, 
flowing  north  35  miles  and  emptying  into  the  Red  River  of  the  North  at 
Breckem-idge  and  Wahpeton.  The  Red  River,  here  turning  abruptly  from 
its  western  course,  flows  thence  north  to  Lake  Winnipeg,  285  miles.  These 
streams  occupy  the  axial  depression  of  a  vast  plain  of  glacial  drift  and 
lacustrine  and  fluvial  deposits,  40  to  50  miles  wide  and  more  than  300 
miles  long,  stretching  from  Lake  Traverse  to  Lake  Winnipeg.  This 
expanse,  widely  famed  for  the  large  harvests  and  superior  quality  of  its 
wheat,  is  commonly  called  the  Red  River  Valley.  It  has  a  very  uniform 
continuous  descent  northward,  averaging  a  little  less  than  1  foot  per  mile. 
So  slight  an  inclination  is  imperceptible  to  the  eye,  as  is  also  the  more 
considerable  ascent,  usually  2  or  3  feet  per  mile,  for  the  first  10  or  15  miles 
to  the  east  and  west  fi-om  the  Red  River.  This  river  flows  along  the  lowest 
portion  of  the  plain,  somewhat  east  of  its  central  line,  in  a  quite  direct 
general  course  from  south  to  north,  but  meanders  almost  everywhere  with 
minor  bends,  which  carry  it  alternately  a  half  mile  to  1  mile  or  more  to 
each  side  of  its  main  course.  Thus  its  length  from  Breckenridge  and 
Wahpeton  to  St.  Vincent  and  Pembina,  forming  the  boundary  between 
Minnesota  and  North  Dakota,  is  397  miles,  according  to  the  surveys  of  the 
United  States  Engineer  Corps,  while  the  distance  in  a  direct  line  is  only 
186  miles;  yet  the  river  nowhere  deviates  more  than  5  or  6  miles  from  this 
straight  line. 

The  Red  River  has  cut  a  channel  20  to  50  feet  deep.  It  is  bordered 
by  only  few  and  narrow  areas  of  bottom-land,  instead  of  which  its  banks 
usually  rise  steeply  on  one  side  and  by  moderate  slopes  on  the  other  to  the 
lacustrine  plain,  which  thence  reaches  nearly  level  10  to  30  miles  from  the 
river.  Its  tributaries  cross  the  plain  in  similar  channels,  which,  as  also 
the  Red  River,  have  occasional  gullies  connected  with  them,  dry  through 
the  most  of  the  year,  varying  from  a  few  hundred  feet  to  a  mile  or  more 
in  length.  Between  the  drainage  lines  areas  often  5  to  15  miles  wide 
remain  unmarked  by  any  water  courses.  The  hig'hest  portions  of  these 
tracts  are  commonly  from  2  to  5  feet  above  the  lowest.  The  material  of 
the  lower  part  of  this  valley  plain,  shown  in  the  banks  of  the  Red  River 


THE  RED  EIVEE  VALLEY.  21 

and  i-eaching  several  miles  from  it  (excepting  a  morainic  belt  of  till  crossing- 
the  river  at  Goose  Rapids),  is  fine  clayey  silt,  horizontally  stratified;  but 
the  south  end  and  large  areas  of  each  side  of  the  plain  are  mainly 
unstratified  bowlder-clay,  which  differs  from  the  rolling  or  undulating  till  of 
the  adjoining  region  chiefly  in  having  its  surface  nearly  flat.  Both  these 
formations  are  almost  impervious  to  water,  which  therefore  in  the  rainy 
season  fills  their  shallow  depressions;  but  these  are  very  rarely  so  deep  as 
to  form  permanent  lakes.  Even  sloughs  that  continue  marshy  through  the 
summer  are  infrequent,  but,  where  they  do  occur,  cover  large  tracts,  usually 
several  miles  in  extent. 

In  crossing  the  vast  plain  of  the  Red  River  Valley  on  clear  days  the 
higher  land  at  its  sides  and  the  groves  along  its  rivers  are  first  seen  in  the 
distance  as  if  their  upper  edges  were  raised  a  little  above  the  horizon,  with 
a  very  narrow  strip  of  sky  below.  The  first  appearance  of  the  tree  tops 
thus  somewhat  resembles  that  of  dense  flocks  of  birds  flying  very  low 
several  miles  away.  By  rising  a  few  feet,  as  from  the  ground  to  a  wagon, 
or  by  nearer  approach,  the  outlines  become  clearly  defined  as  a  grove,  with 
a  mere  line  of  sky  beneath  it.  This  mirage  is  more  or  .less  observable  on 
the  valley  plain  nearly  every  sunshiny  day  of  the  spring,  summer,  and 
autumn  months,  especially  during  the  forenoon,  when  the  lowest  stratum 
of  the  air,  touching  the  surface  of  the  ground,  becomes  heated  sooner  than 
the  strata  above  it. 

A  more  complex  and  astonishing  effect  of  mirage  is  often  seen  from 
the  somewhat  higher  land  that  forms  the  slopes  on  either  side  of  the  plain. 
There,  in  looking  across  the  flat  valley  a  half  hour  to  two  hours  after 
sunrise  of  a  hot  day  following  a  cool  night,  the  groves  and  houses,  villages 
and  grain  elevators,  loom  up  to  twice  or  tlii'ice  their  true  height,  and  places 
ordinarily  hidden  from  sight  by  the  earth's  curvature  are  brought  into  view. 
Occasionally,  too,  these  objects,  as  trees  and  houses,  are  seen  double,  being 
repeated  in  an  inverted  position  close  above  their  real  places,  from  which 
they  are  sej^arated  by  a  very  narrow,  fog-like  belt.  In  its  most  perfect 
development  the  mirage  shows  the  upper  and  topsy-turvy  portion  of  the 
view  quite  as  distinctly  as  the  lower  and  true  portion;  and  the  two  are 
separated,  when  seen  from  land  about  a  hundred  feet  above  the  plain,  by 


22 


THE  GLACIAL  LAKE  AGASSIZ. 


an  apparent  vertical  distance  of  75  or  100  feet  for  objects  at  a  distance  of 
6  or  8  miles,  and  300  to  500  feet  if  the  view  is  15  to  20  miles  away. 
Iimnediately  above  the  inverted  images  there  runs  a  level  false  horizon, 
which  rises  slightly  as  the  view  grows  less  distinct,  until,  as  it  fades  and 
vanishes,  the  inverted  groves,  lone  trees,  church  spires,  elevators,  and  houses 
at  last  resemble  rags  and  tatters  hung  along  a  taut  line. 

The  traveler  in  the  Red  River  Valley  is  reminded,  in  the  same  manner 
as  at  sea,  that  the  earth  is  round.  The  surface  of  the  plain  is  seen  only  for 
a  distance  of  3  or  4  miles;  houses  and  grain  stacks  have  their  tops  visible 
first,  after  which,  in  approaching,  they  gradually  come  into  full  view;  and 
the  highlands,  10  or  15  miles  away,  forming  the  side  of  the  valley, 
apparently  lie  beyond  a  wide  depression,  like  a  distant  high  coast. 


1000 


SOO 


1000 


SOO 


¥iG.  2. — Section  across  the  Ked  River  Valley  on  the  latitude  of  Breckenridge  and  Wahpeton.    Horizontal 
scale,  20  miles  to  an  inch :  vertical  scale,  1,000  feet  to  an  inch. 

At  Breckem-idge  and  Wahpeton,  35  miles  north  of  Lake  Traverse,  the 
surface  of  this  plain  is  960  feet  above  the  sea  (fig.  2).  In  17  miles  east  it 
ascends  to  1,080  feet  at  the  highest  beach  of  Lake  Agassiz;  and  on  the 
west  it  rises  in  28  miles  to  1,065  feet  at  the  con-esponding  beach  near 
Wyndmere,  beyond  which  for  8  miles  farther  west  it  maintains  a  level  2  to 
5  feet  below  the  crest  of  that  beach. 

At  Moorhead  and  Fargo,  75  miles  north  of  Lake  Traverse,  the  sm-face 
adjoining  the  Red  River  is  900  to  905  feet  above  the  sea  (fig.  3).  In  the 
first  15  miles  east  it  ascends  about  60  feet.  The  highest  beach  of  Lake 
Agassiz  here  lies  at  Muskoda,  1 7  miles  east  of  the  Red  River,  on  the  slope 
of  a  highland  of  till,  which  rises  in  a  distance  of  6  or  8  miles  to  an 
elevation  of   250  feet  above  the  flat  Red  River  Valley,  having  thus  an 


SECTIONS  ACROSS  THE  RED  RIVER  VALLEY. 


23 


average  ascent  of  30  or  40  feet  per  mile.  On  the  west  the  plain  ascends 
only  50  feet  in  the  first  25  miles,  beyond  which  it  ascends  within  7  miles 
to  1,099  feet  above  the  sea-level  at  the  highest  beach  line,  4^  miles  west  of 
Wheatland,  and  a  similar'  slope  continues  to  a  height  of  1,200  feet  at  a 
distance  of  4  or  5  miles  farther  west. 


Soo 


je:'  lom 


Fig.  3.— Section  across  the  Red  River  Valley  on  the  latitude  of  Moorhead  and  Fargo.     Horizontal  scale,  20 
miles  to  an  inch ;  vertical  scale,  1,000  feet  to  an  inch. 

At  Grrand  Forks,  where  the  Red  Lake  River  joins  the  Red  River,  150 
miles  north  of  Lake  Traverse,  the  surface  of  the  plain*  is  830  feet  above  the 
sea  (fig.  4).  In  the  first  20  miles  east  the  ascent  is  about  75  feet.  Thence 
in  25  miles  southeast  there  is  a  gradual  rise  of  nearly  300  feet  to  the 


Fie.  4.— Section  across  the  Red  River  Valley  from  Larimoreand  Grand  Forks  to  Maple  Lake.     Horizontal 
scale,  20  miles  to  an  inch;  vertical  scale,  1,000  feet  to  an  inch. 

highest  beach  of  Lake  Agassiz,  close  west  and  north  of  Maple  Lake;  but 
in  a  line  passing  due  east  the  surface  ascends  only  about  200  feet  in  an 
equal  distance,  and  continues  at  a  lower  elevation  than  this  beach  to  the 
east  side  of  Red  Lake,  100  miles  from  Grand  Forks.  On  the  west  the 
surface  rises  only  35  feet  in  the  first  14  miles,  beyond  which  it  rises  about 


24 


THE  GLACIAL  LAKE  AGASSIZ. 


300  feet  in  the  next  19  miles  to  1,162  feet  above  sea-level  at  the  highest 
beach  of  Lake  Agassiz,  4J  miles  west  of  Larimore.  The  westward  ascent 
continues  to  1,525  feet  above  the  sea  12  miles  west  of  this  beach. 

At  St.  Vincent  and  Pembina,  near  the  international  boundary,  which  is 
224  miles  north  of  Lake  Traverse,  the  surface  of  the  plain  is  785  to  790 
feet  above  the  sea  (fig.  5).  Eastward  on  the  boundary  it  is  nearly  level, 
rising  only  a  few  feet  in  the  first  10  miles.  Thence  an  ascent  of  about  50 
feet  is  made  in  2  miles  to  the  crest  of  a  slight  ridge.  Farther  east  the 
country  is  wooded,  and  many  extensive  tracts  are  tamarack  swamps.  The 
Lake  of  the  Woods,  about  85  miles  east  from  the  Red  River,  is  1,060  feet 
above  the  sea;  and  the  highest  land  near  the  international  boundary  west 
of  this  lake  is  approximately  1,090  feet.     Continuing  eastward  along  the 


ISOO 


loot 


MAvei. 


Fig.  5. — Section  across  the  Red  River  Valley  on  the  international  boundary.     Horizontal  scale,  20  miles  to 
an  inch ;  vertical  scale,  1,000  feet  to  an  inch. 

boundary,  which  here  is  formed  by  the  Rainy  River  and  Rainy  Lake,  the 
elevation  of  the  highest  beach  of  Lake  Agassiz  is  reached  a  short  distance 
east  from  the  east  end  of  Rainy  Lake,  more  than  200  miles  from  the  Red 
River.  Westward  the  surface  rises  about  40  feet  in  15  miles  from  Pembina 
to  Neche,  and  187  feet  in  the  next  21  miles  along  the  international 
boundary  to  the  base  of  the  great  Cretaceous  escai-pment  called  Pembina 
Mountain,  which,  within  2  miles  farther  west,  ascends  nearly  400  feet  to 
an  elevation  approximately  1,400  feet  above  the  sea. 

These  sections  give  a  good  idea  of  the  average  width  and  elevation  of 
the  flat  plain  to  which  the  name  Red  RiA^er  Valley  seems  to  be  properly 
limited,  both  by  topographic  features  and  by  the  common  usage  of  this 
term.     At  a  distance  of  35  miles  north  of  Lake  Traverse  its  width  is  about 


NORTHWARD  DESCENT  OF  THE  RED  RIVER  VALLEY.  25 

45  miles,  and  its  limits  on  each  side  are  a  slightly  higher  area  of  more 
rolling  contour.  On  the  latitude  of  Moorhead  and  Fargo  its  width  is  about 
40  miles,  and  it  is  bordered  by  prominent  highlands  Avhich  rise  200  to  300 
feet  above  this  broad  A^alley.  On  the  latitude  of  Grand  Forks  its  width  is 
nearly  50  miles,  and  it  is  bordered  on  the  east  by  land  that  rises  slowly  200 
to  300  feet  above  the  plain,  while  on  the  west  the  surface  rises  by  moderate 
slopes  to  a  height  of  600  to  700  feet.  Where  it  is  crossed  by  the  interna- 
tional boundary  the  width  of  this  plain  is  48  miles,  its  limit  on  the  east 
being  a  slightly  higher  and  more  undulating  wooded  region,  Avhile  on  the 
west  it  is  a  conspicuous  terrace-like  ascent  of  several  hundi-ed  feet.  On 
the  average,  for  its  extent  within  the  United  States,  about  one-third  of  the 
width  of  the  Red  River  Valley  is  in  Minnesota  and  two-thirds  in  North 
Dakota. 

The  northward  slope  of  the  lowest  part  of  the  Red  River  Valley, 
along  the  course  of  the  Bois  des  Sioux  and  Red  rivers,  from  Lake  Trav- 
erse, 970  feet,  to  Lake  Winnipeg,  710  feet  above  the  sea,  may  thus  be 
said  to  be  260  feet  in  a  distance  of  320  miles,  averaging  about  10  inches 
per  mile.  The  valley  proper,  however,  does  not  take  on  its  distinctive 
character  in  the  first  10  or  15  miles  of  the  course  of  the  Bois  des  Sioux 
River,  but  10  miles  farther  east  in  Minnesota  the  same  topographic  features 
that  mark  the  Red  River  Valley  continue  south  nearly  to  the  latitude  of 
the  southwest  end  of  Lake  Traverse.  The  elevation  of  this  southern 
extremity  of  the  area  of  Lake  Agassiz  is  1,050  feet  above  the  sea,  being 
90  feet  above  the  surface  at  Breckenridge  and  Wahpeton,  43  miles  distant 
to  the  north,  so  that  this  part  of  the  valley  plain  has  a  northward  descent 
of  2  feet  per  mile.  Thence  to  Moorhead  and  Fargo  the  descent  is  IJ  feet 
per  mile;  next,  for  75  miles  to  Grand  Forks,  it  averages  almost  exactly  1 
foot  per  mile;  and  in  the  74  miles  from  Grand  Forks  to  the  international 
boundary  this  axial  lowest  portion  of  the  valley  falls  about  40  feet,  or  a 
little  more  than  6  inches  per  mile.  In  the  60  miles  thence  to  Winnipeg  the 
descent  is  about  35  feet,  or  7  inches  per  mile,  the  surface  there  being  45 
feet  above  Lake  Winnipeg,  about  35  miles  distant. 


26  THE  GLACIAL  LAKE  AGASSIZ. 


SHORE-LINES. 


Cousidered  in  relation  to  the  general  topography,  the  shore-lines  of 
Lake  Agassiz  are  inconspicuous,  though  they  are  very  distinctly  traceable. 
They  are  usiiallv  marked  by  a  beach  deposit  of  gi-avel  and  sand,  fonning 
a  continuous,  smoothly  rounded  ridge,  such  as  is  found  along  the  shores  of 
the  ocean  or  of  our  gi-eat  Laurentian  lakes  Avherever  the  land  sinks  in  a 
gently  descending  slope  beneath  the  water  level.  The  beach  ridges  of 
Lake  Agassiz  (fig.  6)  commonly  rise  3  to  10  feet  above  the  adjoining  land 

Till  _,^--r.^^'  -^'^^^.^^-^-^^b^-v:-:  s^?^^  TiU,SU6HTiyc/fooeo. 


iCifSL  OFLAJTE  ASASSI2. 


Fig.  6 Typical  aection  across  a  beach  ridge  of  Lake  Agassiz.    Scale,  100  feet  to  an  inch. 

on  the  side  that  was  away  from  the  lake,  and  10  to  20  feet  above  the 
adjoining  land  on  the  side  where  the  lake  lay.  In  breadth  these  ridges 
vary  from  10  to  25  or  30  rods.  In  some  places  they  have  been  cut  through 
and  can'ied  away  by  streams,  and  occasionally  they  are  interrupted  for 
a  quarter  or  a  half  mile,  or  even  2  or  3  miles,  where  the  outline  of  the 
lake  shore  and  the  direction  of  the  shore  cuiTents  prevented  such  accumu- 
lation. Throughout  almost  the  whole  extent  of  Lake  Agassiz  examined 
witliin  the  United  States  the  regular  outlines  of  the  surface,  its  gentle  slope 
toward  this  lake,  and  its  mateiial,  which  nearly  everywhere  is  till,  were  very 
favorable  for  the  formation  of  beach  deposits.     Many  beach  ndges,  record- 


L£i^£Z.  or  LA/f£  /^6ASS/Z 


°^'-'<*~'g'^l 


Fig.  7. — Eroded  terrace  marking  the  shore  of  Lake  Agassiz.    Scale,  100  feet  to  an  inch. 

ing  the  successive  reductions  in  the  elevation  and  area  of  this  lake,  have 
been  traced  in  continuous,  approximately  parallel  coui-ses  along  each  side 
of  the  Red  River  Valley.  PI.  YI  shows  an  exceptionally  massive  beach 
ridgre  marking-  the  hio-hest  shore-line  of  Lake  Agassiz  close  northwest  of 
Maple  Lake,  about  20  miles  east-southeast  from  Crookston,  Minn. 

Another  type  of  shore-lines  is  presented  where  the  lake  has  fonned  a 
terrace  in  the  till  (fig.  7),  with  no  definite  beach  deposit,  the  Avork  of  tlie 
waves  haAaug  been  to  erode  and  cany  away  rather  than  to  accumulate.    The 


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SHORE-LINES  AND  DELTAS.  27 

height  of  these  steep,  wave-cut  slopes  varies  from  10  to  30  feet,  Avhich  is 
indeed  a  very  slight  elevation  in  comparison  with  the  cliffs  of  similar  origin 
on  some  portions  of  the  shores  of  Lake  Michigan  and  others  of  the  Lau- 
rentian  lakes.  No  portions  of  the  beach  ridges,  nor  of  these  low,  eroded 
escarpments  marking  the  margin  of  Lake  Agassiz,  are  noteworthy  objects 
in  the  view  from  points  so  far  away  as  2  or  3  miles,  but  nearer  at  hand  they 
appear  sufficiently  impressive  when  the  mind  reverts  to  the  receding  ice- 
sheet  and  this  great  glacial  lake  by  which  they  were  made. 

DELTAS. 

Sand  and  gravel  deltas,  so  extensive  as  to  be  important  features  in  the 
topography,  were  formed  in  the  edge  of  Lake  Agassiz  during  its  earliest 
and  highest  stage  by  several  of  its  tributary  streams.  Such  deltas  were 
brought  into  the  east  side  of  the  lake  liy  the  Buffalo  and  Sand  Hill  rivers, 
and  into  the  west  side  by  the  Sheyenne,  Pembina,  and  Assiniboine  rivers. 
They  all  consist  for  the  greater  part  of  modified  drift,  derived  directly  from 
the  ice-sheet  in  which  it  had  been  held;  and  another  delta  of  this  lake, 
extending  south  from  the  Elk  Valley,  in  North  Dakota,  was  deposited  by  a 
large  glacial  river,  flowing  where  no  river  exists  now. 

The  delta  of  the  Buffalo  River  is  well  seen  from  the  Northern  Pacific 
Railroad,  on  which  the  traveler  going  westward  enters  the  delta  area  at 
Muskoda  and  passes  through  it  in  the  next  2^  miles.  Its  eastern  border 
bears  a  massive  beach  ridge,  15  feet  thick,  of  coarse  gravel  and  sand,  which 
marks  the  highest  level  of  the  lake;  but  the  chief  mass  of  the  delta, 
attaining  a  thickness  of  25  to  75  feet,  is  stratified  sand,  with  occasional 
layers  of  fine  gravel,  as  exhibited  in  the  railroad  cuts. 

The  Pembina  River  intersects  the  highest  part  of  its  delta,  which  rises 
200  to  250  feet  above  the  stream.  Its  eroded  eastern  border,  carved  in  a 
steep  escarpment  by  the  waves  of  Lake  Agassiz  while  this  lake  fell  to  suc- 
cessive lower  stages,  forms  the  "First  Pembina  Mountain,"  passing  from 
south  to  north  and  northwest  by  Walhalla  as  a  very  conspicuous  wooded 
bluff  100  to  175  feet  above  the  flat  prairie  of  the  Red  River  Valley  at  its 
base,  with  its  crest  1,100  feet  to  nearly  1,200  feet  above  the  sea. 


28  THE  GLACIAL  LAKE  AGASSIZ, 


DUNES. 


Large  tracts  of  the  deltas  tormed  by  the  Sand  Hill,  Sheyenne,  and 
Assiniboine  rivers  have  been  heaped  up  by  the  wind  in  dunes  or  di-it'tiug- 
sand  hills,  which  vary  in  height  from  25  to  100  feet.  Their  extremely 
uneven  contour,  and  their  singular  aspect,  being  partly  covered  by  small 
trees  and  bushes,  but  in  many  places  wholly  destitute  of  vegetation  where 
they  are  now  gullied  and  drifted  by  the  wind,  make  these  hills  a  unique 
element  in  the  topography  of  the  Red  River  basin.  The  worthlessness  of 
the  dunes  for  agriculture  is  also  in  marked  contrast  with  the  great  fertility 
of  the  surrounding  prairie,  bvit  they  frequently  include  patches  of  good 
pasturage  in  the  intervening  hollows. 

On  the  delta  of  the  Sand  Hill  River,  dunes  25  to  75  feet  high  have 
been  formed  in  in-egular  groups  and  series,  scattered  over  a  tract  about  a 
mile  wide  and  extending  3  or  4  miles  south  from  the  Sand  Hill  River, 
besides  a  single  isolated  group  on  its  north  side.  Their  highest  points  are 
1,180  to  1,200  feet  above  the  sea. 

Portions  of  the  originally  flat  sand  and  gi'avel  beds  brought  into  Lake 
Agassiz  by  the  Sheyenne  have  been  blo^^n  into  dunes,  which  vary  from  a 
few  feet  to  more  than  a  hundred  feet  in  height,  and  cover  areas  5  to  15 
miles  long  and  1  to  3  miles  wide.  Their  summits  are  1,100  to  1,150  feet 
above  the  sea.  The  most  southeastern  of  these  large  areas  of  conspicuous 
sand  hills  of  the  Sheyenne  delta  lies  close  south  of  the  Wild  Rice  River, 
and  is  continued  southeastward  several  miles  by  a  lower  belt  of  such 
hillocks  to  a  high  isolated  cluster  of  them  called  the  "Lightning's  Nest" 
(PI.  VII). 

In  Manitoba,  wind-blown  sand  hills  border  the  Assiniboine  River  in 
many  places  along  a  distance  of  60  miles,  from  near  Brandon  to  near 
Portage  la  Prairie,  lying  on  the  very  extensive  Assiniboine  delta. 

The  time  of  formation  of  the  dunes  on  all  these  deltas  was  probably 
soon  after  the  withdi-awal  of  Lake  Agassiz,  before  vegetation  had  spread 
over  the  surface.  The  winds  could  then  erode  more  rapidly  than  now,  and 
heaped  up  these  hills  of  sand  in  nearly  their  present  size  and  height;  but 
it  is  evident  also  that  their  forms  have  been  constantly  undergoing  slight 
changes  since  that  time. 


. 


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J-      J3 

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I 


WOODED  EEGION  ON  THE  EAST  AND  NORTH.  29 

WOODED   REGION    OP  NORTHERN  MINNESOTA   AND   OF    MANITOBA  AND    KEEWATIN, 

PARTLY    COVERED    BY    THIS    LAKE. 

East  from  the  flat  prairie  of  the  Red  River  Valley  is  the  undulating' 
and  in  part  rolling  and  hilly  wooded  region  of  northern  Minnesota  and 
eastern  Manitoba.  This  is  a  difficult  district  for  exploration,  as  the  greater 
part  of  it  has  neither  settlement  nor  roads,  excepting  those  of  the  scanty 
population  of  Ojibway  Indians,  who  maintain  themselves  chiefly  by  hunting 
and  fishing  and  live  in  nearly  the  same  manner  as  when  Beltrami  crossed 
this  country  from  the  Red  River  Valley  to  the  Upper  Mississippi  River 
seventy  years  ago.  Their  abodes  are  usually  on  the  shores  of  lakes  and 
streams,  which  they  navigate  in  birch-bark  canoes;  and  this  is  the  only 
practicable  means  of  travel  for  geologic  exploration.  Considerable  tracts, 
especially  west  of  the  Lake  of  the  Woods  and  south  to  Red  Lake,  are 
tamarack  swamps,  morasses,  and  quaking  bogs,  called  "muskegs,"  which 
extend  many  miles  and  can  be  crossed  only  when  they  are  frozen  in  winter. 
Northwest  of  Red  Lake  a  large  area,  described  and  named  Beltrami  Island 
in  Chapter  VI,  rises  to  a  maximum  height  of  about  100  feet  above  the 
hig'hest  level  of  Lake  Agassiz.  Eastward  from  Beltrami  Island  a  large  tract 
between  Red  Lake  and  the  Rainy  River,  reaching  to  the  Big  and  Little 
Forks,  lies  50  to  150  feet  below  the  highest  stage  of  Lake  Agassiz;  but 
the  northeastern  part  of  this  area  may  have  been  still  covered  by  the 
waning  ice-sheet  when  the  lake  stood  at  that  height.  On  account  of  the 
impracticability  of  tracing  the  shores  of  Lake  Agassiz  through  this  wooded 
and  uninhabited  region,  the  northeastern  limits  of  this  glacial  lake,  where 
the  shore  in  its  successive  stages  passed  from  the  land  surface  to  the  barrier 
of  the  receding  ice-sheet,  remain  undetermined. 

The  part  of  Keewatin  north  and  northeast  of  Lake  Winnipeg  presents 
no  considerable  elevations,  but  is  mainly  a  broad,  nearly  flat  expanse, 
similar  to  the  Red  River  Valley  and  the  lake  district  of  Manitoba,  slowly 
declining  to  the  sea-level.     Dr.  Robert  Bell  writes  of  it  as  follows: 

The  region  through  which  the  upper  two- thirds  of  the  Nelson  River  flows  maybe 
described  as  a  tolerably  even  Laureutian  plain,  sloping  toward  the  sea  at  the  rate  of 
about  2  feet  in  the  mile.  The  river,  for  the  first  hundred  miles  from  Great  Playgreen 
Lake,  does  not  flow  in  a  valley,  but  spreads  itself  by  many  channels  over  a  consider- 


30  THE  GLACIAL  LAKE  AGASSIZ. 

able  breadth  of  country.  This  tendency  to  give  off  "stray"  channels  is  character- 
istic of  numerous  rivers  throughout  the  northern  and  comparatively  level  Laurentiau 
regions,  but  it  is  perhaps  more  strongly  marked  in  the  Nelson  than  in  any  other.  In 
the  above  section  of  this  stream  the  straggling  channels  are  of  all  sizes,  from  mere 
brooks  up  to  large  rivers.  *  *  *  The  general  aspect  of  the  country  *  *  *  is 
even  or  shghtly  undulating,  the  highest  points  seldom  rising  more  than  30  or  40  feet 
above  the  general  level. 

The  country  adjoining  the  lower  part  of  this  river,  according  to  the 
same  explorer,  has  a  similar  contoiu-,  only  moderately  uneven;  but  the 
channel  of  the  river,  excepting  in  the  10  miles  next  to  its  mouth,  is  deeply 
eroded.  Its  inclosing  bluffs  vary  in  height  from  100  to  200  feet  between 
Broad  Rapid,  where  the  river  is  approximately  125  feet  above  the  sea,  and 
Gillams  or  Lower  Seal  Island,  which  is  at  the  head  of  the  tide,  about  20 
miles  from  Hudson  Bay.^ 

COUNTRY  BOEDERIlSrG  LAKE  AGASSIZ    Ol^    THE    EAST. 

Northern  Minnesota,  from  Maple,  Red,  and  Rainy  lakes  east  to  the 
high  northwestern  shore  of  Lake  Superior  and  south  to  Mille  Lacs  and  the 
Leaf  Hills,  varies  in  its  average  height  from  the  highest  level  of  Lake 
Agassiz  to  600  feet  above  it,  or  from  1,200  to  1,800  feet  above  the  sea.  It 
is  mostly  a  moderately  rolling  or  hilly  country,  abounding  with  little  lakes 
which  fill  its  depressions.  The  watershed  dividing  the  basin  of  Lake 
Agassiz  from  the  basins  of  Lake  Superior  and  the  Mississippi  culminates 
northeastward  in  the  Giants  Range  and  the  Mesabi  Range,  and  southwest- 
ward  in  the  Leaf  Hills.  These  ranges  of  hills  rise  several  hundred  feet 
above  the  average  height  of  the  disti-ict.  Excepting  its  western  border 
from  near  Maple  Lake  southward,  where  it  is  in  large  part  prame  like  the 
adjacent  Red  River  Valley,  this  district  is  covered  with  an  almost  unbroken 
forest.  Toward  the  east  it  forms  a  plateau,  in  part  hilly  and  mountainous 
and  in  part  only  moderately  undulating  or  nearly  flat,  everywhere  well 
wooded  and  dotted  with  frequent  small  lakes,  bordering  the  entne  northern 
shore  of  Lake  Superior,  above  which  it  rises  600  to  1,000  feet;  and  thence  a 
downward  slope,  characterized  by  the  same  general  features,  stretches  west 

'  Geol.  Surrey  of  Canada,  Eeports  of  Progress  for  1877  to  1879. 


THE  GIANTS  AND  MESABI  EANGES.  31 

and  north  with  gradually  declining-  surface  to  Lake  Winnipeg  and  Hudson 
Bay.  The  highest  point  of  this  plateau  on  the  line  of  the  Canadian  Pacific 
Railway  is  1,584  feet  above  the  sea,  or  982  and  874  feet,  respectively, 
above  Lakes  Superior  and  Winnipeg. 

Giants  Range. — The  Giants  Range  extends  in  a  west-southwest  course 
from  north  of  Gunflint  Lake,  on  the  international  boundary,  to  the  lakes 
on  the  Embarras  River,  about  15  miles  south  of  Vermilion  Lake,  and  its 
mostly  lower  continuation,  forming  the  northern  border  of  the  Mesabi  iron- 
bearing  belt,  appears  to  reach  to  the  falls  of  Prairie  River  and  Pokegama 
Falls,  on  the  Mississippi.  Southeast  and  south  of  Vermilion  Lake,  where 
it  has  been  called  the  Mesabi  Range,  Prof  N.  H.  Winchell  describes  it  as 
"a  distinct,  narrow  ridge,  rising  about  200  feet  above  the  average  level  on 
either  side.  It  is  intersected  at  several  places  by  streams."  Its  elevation 
there  is  mainly  about  1,800  feet  above  the  sea,  but  eastward  it  rises  to 
nearly  2,200  feet. 

Mesabi  Range.— Frohssor  Winchell  resti-icts  the  title  "Mesabi  Range"  to 
a  more  prominent  and  persistent  belt  of  highland  5  to  15  miles  south  of  the 
foregoing,  with  which  it  is  approximately  parallel.  The  eastern  and  highest 
part  of  its  extent  is  commonly  known  by  this  name.  "It  is,  however,  broad 
as  well  as  high,  and  holds  on  its  summit  some  of  the  largest  lakes  of  tliis 
part  of  the  State,  Brul^  Lake  being  one.  It  is  characterized  by  bare  rock, 
alternating  with  peat  bogs  and  muskegs,  with  scattered  and  stunted  spruces. 
*  *  *  Its  width  is  sometimes  15  miles,  but  generally  from  4  to  6; 
and  in  most  places,  especially  north  from  Grand  Marais  and  south  from 
Ogisldiie  Muncie  Lake,  its  rounded  low  crest  is  distinct  and  narrowed  to 
less  than  a  mile."  ^  The  suimnits  of  the  Mesabi  Range  and  of  outlying  hills 
near  are  1,800  to  2,230  feet  above  the  sea,  including  the  highest  points  of 
land  in  Minnesota.  The  latter  elevation  is  that  of  hills  adjoining  the  south 
side  of  Winchell  Lake,  as  determined  by  leveling  for  the  Minnesota 
Geological  Survey.  Near  the  international  boundary  the  Mesabi  Range 
extends  from  south  of  Gunflint  Lake  eastward  to  South  and  North  lakes 
and  the  sovith  side  of  Mountain  Lake. 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Thirteenth  Annual  Report,  for  1884,  p.  22. 


32  THE  GLACIAL  LAKE  AGASSIZ. 

These  ranges  of  hills  cross  the  international  boundary  respectively 
about  90  and  120  miles  east  of  Rainy  Lake,  which,  as  before  stated,  was 
the  extreme  eastern  arm  of  the  glacial  Lake  Agassiz  at  its  highest  stage, 
unless  that  area  was  still  ice-covered;  and  their  western  portions  are 
respectively  65  and  75  miles  south-southeast  of  the  east  end  of  Rainy  Lake. 
They  coincide  nearly  with  the  line  of  watershed  dividing  the  basin  of 
Rainy  Lake  and  River  from  that  of  Lake  Superior;  but  this  watershed 
takes  a  less  direct  course,  winding  its  way  circuitously  over  this  generally 
uneven  and  hilly  region.  On  the  international  boundary  the  belt  between 
the  Giants  and  Mesabi  ranges  is  drained  partly  through  the  former  to  Rainy 
Lake  and  partly  through  the  latter  to  Lake  Superior;  and  the  Embarras 
River,  which  sends  its  waters  to  the  St.  Louis  River  and  Lake  Supei-ior,  has 
its  source  north  of  the  northern  range. 

About  Vermilion  Lake  and  the  upper  EmbaiTas  River  the  average 
height  of  the  country  is  1,500  to  1,600  feet.  Thence  the  surface  falls 
slowly  westward  to  the  vicinity  of  Pokegama  Falls,  Lake  Winnebagoshish, 
and  Leech  and  Cass  lakes,  where  the  mean  elevation  is  from  1,300  to  1,400 
feet.  Still  farther  west  it  rises  to  1,500  and  1,600  feet  about  Lake  Itasca 
and  the  White  Earth  Agency.  The  hills  of  these  areas  consist  of  morainic 
accumulations  of  glacial  drift,  and  are  not  so  high  and  massive  as  the 
Giants  and  Mesabi  ranges,  which,  near  the  international  boundary  and  west 
to  the  EmbaiTas  River,  are  mostly  projecting  knobs  and  ridges  of  the  bed- 
rock. 

Mesabi  and  Itasca  moraines. — Drift  hills  and  shoil  ridges,  having 
heights  from  50  to  200  feet  or  more,  extend  in  an  approximately  east  to 
west  belt,  to  which  I  have  applied  the  name  Mesabi  moraine,  from  the  lakes 
of  the  Embarras  River  to  Deer  and  Bowstring  lakes  and  the  northeast  side 
of  Lake  Winnebagoshish.  Its  continuation  northwestward  probably  passes 
to  the  prominent  terminal  moraine,  100  to  200  feet  high,  between  the  north 
and  south  portions  of  Red  Lake,  east  of  the  Nan-ows.  Eastward  from  the 
Embarras  River,  this  morainic  belt  coincides  in  part  with  the  Giants  and 
Mesabi  ranges  for  a  considerable  distance,  so  that  the  elevations  of  rock 
forming  those  heights  are  overspread  and  sometimes  concealed  by  morainic 


THE  LEAF  HILLS.  33 

drift  deposits ;  but  it  appears  to  pass  finally  south  of  those  ranges  and  to 
reach  the  north  shore  of  Lake  Superior  in  the  vicinity  of  Grand  Portage. 

An  approximately  parallel  morainic  belt,  12  to  25  miles  distant  to  the 
south  and  west,  lies  on  the  south  side  of  Pokegama  and  Leech  lakes  and 
reaches  west  to  Itasca  Lake,  where  it  bends  to  a  northerly  course.  Its  very 
irregular  hills  and  ridges  rise  50  to  250  feet  above  the  adjoining  lakes  and 
streams.  This  belt,  especially  prominent  at  the  head  of  the  Mississippi 
River,  I  have  called  the  Itasca  moraine.^ 

Leaf  Hills. — From  Itasca  Lake  and  the  White  Earth  Agency  the 
surface  gradually  falls  southward  to  Detroit,  1,364  feet  above  the  sea. 
Thence  a  mean  elevation  of  1,350  to  1,400  feet  extends  south  through 
Ottertail  and  Douglas  counties  along-  the  low  plateau  that  forms  the  height 
of  land  between  the  Red  and  Mississippi  I'ivers,  east  of  the  south  part  of 
Lake  Agassiz.  Upon  this  area,  in  southern  Ottertail  County,  are  the  Leaf 
Hills,  whose  highest  portions  rise  100  to  350  feet  above  the  general  level, 
or  1,500  to  1,750  feet  above  the  sea,  being  the  most  prominent  morainic 
accumulations  found  within  the  State  of  Minnesota.  They  reach  in  a 
semicircle  from  Fergus  Falls  southeast  to  the  south  line  of  the  county,  and 
thence  east  and  northeast  to  East  Leaf  Lake,  a  total  distance  of  50  miles. 
In  the  first  20  miles,  or  from  Fergus  Falls  to  the  north  side  of  Lake  Claris- 
tina,  at  the  northwest  corner  of  Douglas  County,  these  morainic  deposits 
are  divided  into  two  or  three  belts  of  roughly  hilly  land,  with  intervening 
areas  of  smoother  contour.  For  the  next  20  miles  to  the  east  and  northeast 
they  form  a  range  5  to  3  miles  wide,  composed  of  very  irregular,  roughly 
outlined  hills,  100  to  more  than  300  feet  high,  widely  known  by  the  name 
Leaf  Mountains.  Northeast  of  East  Leaf  Lake,  where  this  moraine  is 
crossed  by  the  road  from  Wadena  to  Ottertail  Lake,  its  elevations  rise 
only  about  100  feet  and  are  named  Leaf  Hills,  which  seems  a  more 
appropriate  title  and  should  include  the  highest  part  of  the  range.  The 
common  name  has  currency  because  they  are  the  only  hills  in  this  part  of 
Minnesota  that  are  conspicuously  seen  at  any  great  distance. 

'Detailed  descriptions  of  these  and  other  moraines  crossing  the  basin  of  Lake  Agassiz  are  given 
in  Chapter  IV. 

MON  XXV 3 


34  THE  GLACIAL  LAKE  AGASSIZ. 

The  Leaf  Hills  are  crossed  northwest  of  Parkers  Prairie  by  a  road  that 
winds  3  or  4  miles  among  their  knolls,  hills,  and  short  ridges,  rising  about 
100  feet  above  the  land  on  each  side.  Again,  the  road  from  Alexandria  to 
Clitherall  crosses  this  range  in  the  township  of  Leaf  Mountain,  the  summit 
of  the  road  being  near  the  south  line  of  this  township,  about  1,525  feet 
above  the  sea.  The  top  of  a  hill  a  quarter  of  a  mile  east  of  the  road 
here,  and  about  125  feet  higher,  affords  a  fine  view  of  these  "mountains" 
(PI.  VIII),  which  westward  and  northeastward  rise  in  most  tumultuous 
confusion  150  to  250  feet  or  more  above  the  intervening  depressions. 
They  are  massive,  though  very  irregular  in  contour,  with  steep  slopes. 
No  prevailing  trend  is  noticeable.  Between  them  are  inclosed  frequent 
lakes,  which  vary  from  a  few  rods  to  a  mile  in  length,  and  one  of  the  largest 
lies  at  the  northeast  foot  of  this  hill.  The  material  is  chiefly  unmodified 
drift,  nearly  like  that  which  forms  very  extensive,  gently  undulating  tracts 
elsewhere.  The  principal  difference  is  that  rock  fragments,  large  and 
small,  are  generally  much  more  numerous  upon  these  hills,  and  occasionally 
they  occur  in  great  abundance. 

South  of  the  Leaf  Hills  the  country  adjoining  Lake  Agassiz  is  an 
expanse  of  smoothly  undulating  or  rolling  till,  1,200  to  1,075  feet  above 
the  sea.  So  slight  are  its  elevations  and  depressions,  usually  differing  from 
each  other  by  10  to  25  feet,  that  in  an  extensive  prospect  these  inequalities 
are  lost  sight  of,  and  the  land  seems  bounded  by  a  level  line  at  the  horizon. 
This  contour  extends  south  through  Grant  and  Stevens  counties,  and  thence 
more  than  100  miles  southeast,  descending  on  the  average  about  a  foot  per 
mile  along  the  wide,  slightly  undulating  basin  of  the  Minnesota  River, 
which  seems  to  be  a  continuation  of  the  same  topographic  belt  that  forms 
the  Red  River  Valley. 

COUNTRY  WEST    OF    LAKE  AGASSIZ. 

Along  the  west  side  of  the  basins  of  the  Minnesota  River,  of  the  Red 
River  Valley,  and  of  Lakes  Manitoba  and  Winnipegosis,  the  surface  rises 
from  200  or  300  to  1,000  feet  above  their  slightly  undulating  or  quite  flat 
belt  of  lowland.  No  other  feature  in  the  contour  of  the  northwestern 
States  and  adjoining  British  territory  is  more  noteworthy,  extended,  and 


t.  L      ■  .-AiHi^'ltr 


OOTEAU  DES  PRAIRIES  AND  MANITOBA  ESCARPMENT.  35 

prominent  than  this,  excepting  perhaps  the  ascent  along-  the  similar  and 
parallel  Coteau  du  Missouri.  The  latter,  however,  lacks  the  accompani- 
ment of  such  a  continuous  broad  depression  beside  it.  This  wide  valley, 
occupied  by  Lakes  Winnipeg,  Manitoba,  and  others,  and  by  the  Red  and 
Minnesota  rivers,  varying  in  elevation  from  710  to  1,100  feet  above  the 
sea,  is  the  base  of  the  slowly  ascending  expanse  of  the  great  plains  which 
rise  thence  westward  to  a  height  somewhat  exceeding  4,000  feet  above  the 
sea-level  at  the  foot  of  the  Rocky  Mountains,  on  the  international  boundary. 
Most  of  this  elevation  is  attained  by  a  gradual  slope,  averaging  4  or  5  feet 
per  mile  throughout  the  distance  of  730  miles  from  the  Red  River  to  the 
mountains;  but  at  two  lines,  extending  from  south  to  north  or  north- 
west, first  on  the  west  side  of  this  valley  and  again  in  the  Coteau  du 
Missouri,  100  to  200  miles  farther  west,  the  surface  rises  more  rapidly  sev- 
eral hundred  feet  within  a  few  miles  by  a  terrace-like  ascent.  The  first 
was  the  western  shore  of  Lake  Agassiz,  and  continuing  south  and  southeast 
held  the  same  relation  to  an  earlier  glacial  lake  which  occupied  the  basin 
of  the  Minnesota  and  Blue  Earth  rivers. 

The  southern  portion  of  this  line  of  elevation  is  the  massive  and  high 
Coteau  des  Prairies.  Its  lower  continuation  from  the  head  of  the  Coteau 
des  Prairies,  west  of  Lake  Traverse,  for  the  next  175  miles  northward,  bears 
no  name,  and  is  scarcely  more  conspicuous,  or  in  some  parts  even  less  so, 
than  the  moderate  ascent  that  forms  the  opposite  border  of  the  Red  River 
Valley  in  Minnesota.  Farther  north  this  line  of  higher  land  rises  abruptly 
300  to  500  feet  in  Pembina  Mountain,  and  from  500  to  1,000  feet  or  more 
in  Riding  and  Duck  mountains  and  the  Porcupine  and  Pasquia  hills.  All 
of  these  are  successive  parts  of  a  A'-ery  i-emarkable  terrace-like  escarpment, 
called  by  Mr.  J.  B.  Tp-rell  the  Manitoba  escarpment,^  stretching  from  North 
Dakota  by  the  west  side  of  Lakes  Manitoba  and  Winnipegosis  to  the  Sas- 
katchewan River.  Its  portions  thus  differently  named  are  divided  by  deep 
and  broad  valleys  eroded  by  intersecting  sti'eams. 

This  whole  belt  of  highland,  reaching  in  a  nearly  direct  north-north- 
west course  about  800  miles,  may  thus  be  considered  in  tlu-ee  parts.  At 
the  south  a  quarter  of  its  length  is  the  great  plateau-like  ridge  of  the 

1  Am.  Geologist,  Vol.  VIII,  ijp.  19-28,  July,  1891. 


36  THE  GLACIAL  LAKE  AGASSIZ. 

Coteau  des  Prairies.  Next,  a  nearly  equal  extent,  is  the  less  elevated  high- 
land that  gradually  rises  west  of  the  Red  River  Valley,  between  it  and  the 
Sheyenne  River  and  Devils  Lake.  The  northern  half  is  a  somewhat  inter- 
rupted, mountain-like  escarpment,  lying  mainly  in  Manitoba,  whose  top, 
like  the  highland  just  mentioned,  is  the  verge  of  plains  that  extend  thence 
westward,  generally  with  a  nearly  level  but  slowly  ascending  surface, 
excepting  where  they  are  channeled  and  irregularly  sculptured  by  stream 
erosion.  Occasional  groups  of  hills  also  rise  above  the  average  height  of 
these  plains,  as  Turtle  Mountain  and  others  farther  northwest.  Beneath 
their  thin  covering  of  drift  these  hilly  tracts  contain  remnants  of  older  for- 
mations, of  which  the  portions  formerly  continuous  between  these  elevations 
and  on  each  side  have  been  eroded  and  carried  away. 

The  accompanying  maps,  which  form  Pis.  IX  and  X,  giving  altitudes 
as  determined  chiefly  by  railway  surveys  upon  the  area  of  Lake  Agassiz 
and  the  adjoining  country,  show  the  extent  and  height  of  the  Manitoba 
escarpment,  of  portions  of  the  Coteau  des  Prairies  and  the  Coteau  du 
Missouri,  and  of  the  region  extending  eastward  from  Lake  Agassiz  to 
Hudson  and  James  bays  and  the  great  Laurentian  lakes. 

THE    COTEAU    UES    PRAIRIES. 

A  large  area  extending  from  south-southeast  to  north-northwest  in 
southwestern  Minnesota  and  the  northeast  part  of  South  Dakota,  and  ter- 
minating on  the  west  side  of  the  south  end  of  Lake  Agassiz,  has  an  eleva- 
tion from  500  to  1,000  feet  above  the  Minnesota  River,  and  from  1,300  to 
2,000  feet  above  the  sea.  Upon  this  highland  district  are  the  sources  of 
the  Lac  qui  Parle,  Yellow  Medicine,  Redwood,  and  Cottonwood  rivers,  trib- 
utary to  the  Minnesota;  of  the  Des  Moines  River;  and  of  the  Little  Sioux 
and  Big  Sioux  rivers,  tributary  to  the  Missouri.  The  outermost  of  the  series 
of  terminal  moraines  of  the  waning  ice-sheet,  denominated  the  Altamont 
moraine,  generally  lies  on  the  highest  portion  of  this  area,  which  extends 
in  Minnesota  from  southeastern  Nobles  County  in  a  nearly  north-north- 
west course,  passing  west  of  Worthington,  through  southwestern  Murray 
County,  the  northeastern  township  of  Pipestone  County,  and  southwestern 
Lincoln  County,  by  the  west  ends  of  Lakes  Benton,  Shaokatan,  and  Hen- 


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SECTION  ACROSS  THE  COTEAU  DES  PRAIRIES.  37 

dricks  into  South  Dakota,  where  it  continues  in  the  same  course  tlu'ough 
Deuel  and  Grant  counties  and  the  Sisseton  and  Wahpeton  Indian  Reserva- 
tion. It  thus  reaches  past  the  sources  of  the  Big  Sioux  River,  and  farther 
northward  becomes  the  divide  between  the  head  streams  of  the  Minnesota 
and  Wild  Rice  rivers  on  the  east  and  tlie  James  River  on  the  west.  This 
elevated  tract,  extending  200  miles,  was  called  by  the  earliest  French 
explorers  the  Coteau  des  Prairies,  meaning  the  Highland  of  the  Prairies. 
This  name,  according  to  Nicollet,  alludes  to  its  conspicuous  appearance, 
"looming  as  it  were  a  distant  shore,"  when  viewed  from  the  valleys  of  the 
Minnesota  and  James  rivers,  as  is  very  noticeable  from  the  vicinity  of  Lakes 
Traverse  and  Big  Stone  and  from  the  highest  points  near  the  Minnesota 
River  for  ^Jerhaps  20  miles  below  Big  Stone  Lake.  Farther  southeast  this 
title  was  applied  to  the  first  prominent  ascent  above  the  broad,  gently 
undulating  expanse  that  reaches  everywhere  20  or  30  miles  from  the  Min- 
nesota River. 

In  crossing  the  Coteau  des  Prairies  from  northeast  to  southwest  there 
is  generally  a  very  gradual,  smooth  slope,  rising  100  to  300  feet  in  5  to  15 
miles.  Then  comes  a  steeper  ascent,  which  amounts  to  300  feet  or  more 
within  a  width  of  2  or  3  miles,  coinciding  through  the  greater  part  of  its 
extent  with  the  tract  of  knoUy  and  hilly  diift  that  forms  the  second  or  Gary 
moraine.  The  average  height  beyond,  sometimes  after  a  slight  descent, 
continues  to  rise,  but  only  slowly,  amounting  to  100  or  150  feet  in  crossing 
the  smoother,  undulating  or  rolling  area,  6  to  15  miles  wide,  between  this 
and  the  outer  morainic  range,  which  next  rises  100  to  200  or  300  feet  within 
2  or  3  miles  and  forms  the  crest  of  the  highland  along  nearly  its  whole 
extent.  West  of  this  moraine  in  Minnesota  the  surface  soon  drops  50  to 
li  0  feet,  this  descent  being  greatest  at  the  south  and  diminishing  north- 
ward, and  thence  a  smooth  slope  of  till  falls  southwesterly  some  200  feet 
within  10  miles.  Farther  to  the  north,  from  Lake  Hendricks  nearly  to 
Goodwin,  S.  Dak.,  a  gently  undulating  expanse  of  till,  slightly  lower  than 
this  western  belt  of  di'ift  hills,  extends  from  them  westward,  approximately 
level,  for  a  Avidth  of  several  miles,  beyond  which  a  similar  slope  falls  to  the 
southwest. 


38 


THE  GLACIAL  LAKE  AGASSIZ. 


On  the  Minnesota  division  of  the  Chicago  and  Northwestern  Railway 
the  traveler  gomg  west  enters  the  iiiner  moraine  belt  of  the  Coteau  at  the 
west  edge  of  Minnesota,  a  little  east  of  Grary,  about  1,460  feet  above  the 
sea  (fig.  8).  The  line  crosses  this  belt  obliqiiely,  occupying  about  4  miles, 
and  ascending  some  200  feet.  Then  6  miles  are  moderately  rolling,  mainly 
in  smooth  swells;  and  the  next  6  miles,  lying  partly  on  each  side  of  Alta- 
mont,  are  among  the  knolls  and  small  hills  of  the  outer  moraine,  1,750  to 
1,950  feet  above  the  sea;  succeeded  by  a  smooth,  slightly  undulating  area 
of  till,  which  rises  to  the  summit  of  this  line  near  Goodwin,  2,000  feet 
above  the  sea,  extends  thence  nearly  level  to  Kranzburg,  and  then  descends 
250  feet  by  a  very  gradual  slope  to  Watertown. 


I 


'^  Branc/tes  of  is.c  ^ 


ISOi 


Fig.  8.— Section  across  the  Coteau  des  Prairies  in  Yellow  Medicine  County,  Minn.,  and  Deuel  and  Codington  counties, 
S.  Dak.    Horizontal  scale,  12  miles  to  an  inch ;  vertical  scale,  1,000  feet  to  an  inch. 

The  altitude  of  the  Coteau  des  Prairies  is  due  to  the  Upper  Cretaceous 
formations,  here  spared  and  left  by  preglacial  erosion  as  a  broad  and  high 
ridge,  upon  which  the  drift  deposits  lie,  rather  than  to  extraordinary  thick- 
ness of  the  drift  beyond  that  which  it  commonly  has  on  the  lowlands  at 
each  side.  The  knolls  and  hillocks  of  the  morainic  belts  rise  20  to  50  and 
rarely  75  or  100  feet  above  the  intervening  hollows,  and  the  thickness  which 
they  add  to  the  drift  sheet  of  the  Coteau  des  Prairies  appears  to  be  from  50 
to  150  feet.  That  the  prominence  of  this  liighland  is  not  due  to  these 
morainic  accumulations  is  shown  in  South  Dakota  at  Goodwin  and  farther 
north  by  the  greater  elevation  that  is  reached  within  a  distance  of  2  to  5 
miles  by  the  smooth  sheet  of  till  at  their  west  side,  which  there  foiTQs  the 
watershed  and  beyond  descends  to  the  Big  Sioux  River. 

Nearly  a  constant  elevation,  varying  between  1,950  and  2,050  feet 
above  the  sea,  is  maintained  along  the  entire  northern  half  of  the  Coteau 


ASCENT  WESTWAED  IN  NOETH  DAKOTA.  39 

des  Prairies,  lying  in  South  Dakota.  The  north  end  of  this  highland, 
called  the  Head  of  the  Coteau  des  Prairies,  is  about  35  miles  west-northwest 
of  Lake  Traverse  and  the  south  end  of  Lake  Agassiz.  Within  5  or  6  miles 
farther  north  there  is  a  descent  of  nearly  800  feet  to  a  level  only  about 
1,200  feet  above  the  sea.  Along  the  continuation  of  this  line  northward, 
instead  of  such  a  prominent  massive  ridge,  bordered  by  much  lower  land 
on  each  side,  there  is  a  more  gradual  ascent,  attaining  a  third  or  half  as 
great  elevation  above  the  valley  on  the  east,  with  only  slight  descent  or 
none  thence  westward  to  the  Sheyenne  and  James  rivers. 

ASCENT    FROM   THE    RED    RIVER    VALLEY    IN    NORTH    DAKOTA. 

From  the  Head  of  the"  Coteau  des  Prairies  for  140  miles  north  to  the 
latitude  of  Larimore  and  Devils  Lake  the  highland  bordering  the  west  side 
of  the  Red  River  Valley  rises  by  such  gentle  slopes  that  it  is  not  generally 
seen  conspicuously  from  the  flat  plain  of  this  valley.  Standing  on  the 
upper  beach  of  Lake  Agassiz,  the  observer  sees  a  smoothed  surface 
descending  very  slowly  eastward  within  the  area  of  this  lake,  and  a 
moderately  undulating  or  rolling  surface  rising  slowly  toward  the  west. 
Along  most  of  this  distance,  however,  the  slope  both  to  the  east  and  west 
is  so  slight  that  the  view  in  each  direction  reaches  only  a  few  miles. 

On  the  line  of  the  Fargo  and  Southwestern  Railroad  the  highest  land 
crossed  between  the  west  shore  of  Lake  Agassiz  and  the  Sheyenne  River 
is  1,190  feet  above  the  sea;  and  between  the  Sheyenne  and  James  rivers  it 
is  about  1,400  feet  above  sea-level,  or  500  feet  above  the  central  part  of 
the  Red  River  Valley  at  Fargo. 

The  Northern  Pacific  Railroad  attains  a  height  of  1,440  feet  between 
the  area  of  Lake  Agassiz  and  the  Sheyenne  River,  and  the  highest  land 
between  that  stream  and  the  James  River  is  approximately  1,500  feet, 
being  thus  600  feet  above  Fargo.  By  each  of  these  lines  the  descent  to 
the  James  River  is  only  about  100  feet. 

Between  Larimore  and  Devils  Lake,  at  the  northern  end  of  this  extent, 
where  the  highland  west  of  the  Red  River  Valley  rises  less  prominently 
than  in  the  Coteau  des  Prairies  on  the  south  or  in  Pembina  Mountain  on 
the  north,  there  is  a  slightly  greater  ascent  than  on  the  two  preceding  rail- 
roads which  cross  its  southern  half     At  Larimore,  near  the  highest  western 


40  THE  GLACIAL  LAKE  AGASSIZ. 

shore  of  Lake  Agassiz,  the  elevation  of  the  Great  Northern  Railway  is 
1,134  feet,  or  about  300  feet  above  the  plain  of  the  Red  River  Valley  at 
Grand  Forks.  Thence  the  surface  in  the  next  17  miles  westward  rises  to 
1,525  feet,  and  this  elevation  is  maintained  somewhat  uniformly,  nowhere 
exceeding  1,535  feet  nor  falling  below  1,450  feet,  to  the  city  of  Devils 
Lake,  1,464  feet  above  the  sea,  60  miles  west  of  Larimore. 

THE    MANITOBA    ESCARPMENT. 

A  very  remarkable  series  of  highlands,  forming  the  eastern  limit  of  the 
elevated  plains  of  the  northern  part  of  North  Dakota  jand  of  western 
Manitoba  and  the  Saskatchewan  region,  extends  in  a  north-northwest 
course  400  miles,  from  the  Pembina  Mountain  to  the  Pasquia  Hills.  Along 
much  of  this  distance  a  steep,  mountain-like  escarpment,  which  was  the 
west  shore  of  Lake  Agassiz,  rises  500  to  1,000  feet  above  the  bed  of  that 
lake,  now  the  low  plain  bordering  the  Red  River  and  the  great  lakes  of 
Manitoba.  Topographically,  this  line  of  conspicuous  highlands  is  allied 
with  the  Coteau  des  Prairies  by  their  together  forming  the  western  ascent 
from  the  broad,  continuous  valley  plain,  which  in  its  southeast  part  passes 
from  the  Red  River  Valley  to  the  lowland  of  the  basin  of  the  Minnesota 
River.  Both  the  Coteau  des  Prairies  and  the  Manitoba  escarpment  consist, 
beneath  their  drift  covering,  of  nearly  liorizontal  Cretaceous  shales,  whose 
continuation  has  been  removed  by  erosion  on  both  sides  of  the  Coteau,  but 
only  east  of  the  escarpment. 

Pembina  Mountain. — The  southern  end  of  the  Pembina  Mountain, 
whei-e  it  is  reduced  to  rounded  hills,  about  100  feet  above  the  lowland  at 
their  east  base  and  1,300  feet  above  the  sea,  is  in  section  30,  township  158 
north,  range  56  west,  between  the  south  and  middle  branches  of  Park 
River.  Thence  for  the  next  5  miles  northward  this  ascent  is  merely  a  slope 
that  rises  50  or  60  feet,  or  in  some  portions  only  30  or  40  feet,  within  a 
quarter  or  half  mile  from  east  to  west,  succeeded  beyond  by  a  moder- 
ately rolling  surface  with  slower  ascent  westward.  Along  the  west  line  of 
townships  159  and  160  of  range  56  this  highland  rises  gradually  in  its 
course  from  south  to  north,  attaining  an  elevation  about  1,500  feet  alcove 
the  sea;  and  it  holds  this  height  quite  uniformly  northward  to  the  Pembina 
River,  in  the  south  part  of  township  163,  range  57,  about  5  miles  south  of 


us. GEOLOGICAL  SURVEY, 


MONOGRAPH    XXV.    PL.X 


MAP  WITH  ALTITUDES  OF  THE  SOUTHERN  PORTION  OB^  LAKE  A(iASSIZ  EXPLORED 

\VITII  LEVELLING  IN  MINNESOTA.  NORTH  DAKOTA,  AND  MANITOBA. 

Scale,  abouL  42  miles  Lo  aviinch. 
Area  of  Ltike  A^assiz  I I  Altiliides  in  feet  above  the  .sea  I  ""'°  I 


PEMBINA  MOUNTAm.  41 

the  international  boundary.  It  is  a  prominent  wooded  bluff,  some  300  feet 
high,  extending  in  a  verj'  direct  course  from  south  to  north  or  a  few 
degrees  west  of  north.  From  its  southern  end  to  the  Pembina  River  the 
base  of  this  escarpment  is  1,200  to  1,225  feet  above  the  sea.  The  width 
occupied  by  its  slope  varies  from  a  half  mile  to  2  or  3  miles,  and  from 
its  crest  a  treeless  plateau,  having  a  moderately  rolling  surface,  stretches 
with  slow  ascent  westward.  North  of  the  Pembina  River  its  crest  sinks  to 
about  1,400  feet,  and  its  base  to  about  1,025  feet,  at  the  international 
boundary. 

Where  the  Pembina  River  cuts  through  this  escarpment,  entering  the 
area  of  Lake  Agassiz,  the  eroded  eastern  front  of  its  delta  dejoosit  fonns 
another  conspicuous  bluff,  about  200  feet  high,  falling  in  a  steep,  wooded 
slope  from  1,175  to  975  feet,  approximately,  above  the  sea-level.  The 
delta  bluff,  called  the  "First  Pembina  Mountain,"  is  composed  of  sand  and 
gravel,  and  lies  about  5  miles  east  of  this  more  prolonged  line  of  highland, 
which  is  denominated  in  that  vicinity  the  "Second  Pembina  Mountain." 
The  latter,  throughout  its  entire  extent  both  in  North  Dakota  and  Manitoba, 
is  caused  by  the  outcrop  of  a  continuous  belt  of  almost  level  Cretaceous 
strata,  mostly  overspread  by  glacial  drift. 

The  ascent  of  this  higliland  on  the  international  boundary,  where  it 
occupies  a  width  of  about  1^  miles,  is  described  by  Dr.  G.  M.  Dawson  as 
follows : 

The  eastern  front  of  Pembina  escarpment  is  very  distinctly  terraced,  and  tlie 
summit  of  the  plateau,  even  at  its  eastern  edge,  thickly  covered  with  drift.  The  first 
or  lowest  terrace,  which  is  about  one-third  from  the  prairie  level  toward  the  top  of 
the  escarpment,  does  not  seem  to  preserve  exactly  the  same  altitude.  On  the  boun- 
dary line  its  height  above  the  general  prairie  level  was  found  to  be  about  90  feet,  a 
second  terrace  260  feet,  and  that  of  the  third  level,  or  summit  of  the  plateau,  about 
360  feet.  The  surface  of  the  first  terrace,  which  is  here  wide,  is  strewn  with  bowlders, 
as  is  also  that  of  the  second  terrace  and  plateau  above.  These  are  chiefly  of  Lauren- 
tian  gneiss  and  granite,  but  a  few  smaller  ones  of  limestone  occur.  The  banks  of 
ravines  cutting  the  top  of  the  plateau  and  draining  westward  into  the  Pembina  Eiver 
show  in  some  places  a  great  thickness  of  light-colored,  yellowish,  marly  drift,  with 
few  bowlders  embedded  in  it.' 


'  Report  on  the  Geology  aud  Resources  of  the  Forty-ninth  Parallel,  from  the  Lake  of  the  Woods  to 
the  Rocky  Mountains,  1875,  i).  219. 


42  .  THE  GLACIAL  LAKE  AGASSIZ. 

In  Manitoba  this  escarpment  extends  with  a  north-northwest  course 
by  Mountain  City  and  Thornhill  to  6  miles  east-southeast  of  Treherne,  a 
distance  of  about  50  miles  With  its  extent  in  North  Dakota,  the  whole 
length  of  Pembina  Mountain  is  approximately  80  miles.  Its  crest  north  of 
the  international  boundary  averages  about  400  feet  above  its  base,  or  1,400 
feet  above  the  sea;  but  within  a  few  miles  farther  west  the  rolling  surface 
of  the  highland  rises  100  to  200  feet  higher. 

Northwestward  fi'om  Treherne  the  plateau  of  which  Pembina  Moun- 
tain forms  the  eastern  edge  is  inteiTupted  across  a  distance  of  65  miles  to 
Riding  Mountain.  This  broad  depression  is  occupied  by  the  Assinibolne 
Eiver  and  its  tributaries,  and  by  small  streams  on  the  northeast  wlaich  send 
their  waters  to  Lake  Manitoba.  The  plateau,  indeed,  loses  its  regularity  of 
surface  upon  the  country  farther  north  and  west,  because  it  has  been  eroded 
to  the  depth  of  several  hundi-ed  feet  on  tlie  greater  part  of  the  Assiniboine 
basin. 

Tiger  Hills. — The  border  of  tlie  plateau  south  of  the  Assiniboine, 
reaching  from  close  south  of  Treherne  westerly  50  miles  to  the  elbow  of 
the  Souris  River,  is  called  the  Tiger  Hills.^  It  is  in-egularly  sculptured  in 
steep,  rounded,  massive  hills,  and  is  overspread  by  drift  deposits,  consisting 
partly  of  morainic  accumulations.  For  a  distance  of  40  miles  west  from 
the  Pembina  Mountain  this  belt  occupies  a  width  of  5  to  8  miles,  upon 
which  the  surface  falls  from  south  to  north  300  to  400  feet.  The  country  on 
the  south  has  an  average  elevation  nearly  the  same  as  the  summits  of  the 
hills,  which  yet  rise  very  prominently  as  seen  from  the  lower  region  on  the 
north.  The  western  part  of  the  Tiger  Hills,  extending  10  or  12  miles  east 
and  an  equal  distance  west  from  the  gorge  that  is  cut  through  the  range  by 
the  Som'is,  rises  considerably  above  the  adjoining  nearly  flat  surface  on  each 
side.  The  foot  of  the  belt  of  hills  there  is  100  to  150  feet  lower  on  the 
north  than  on  the  south,  and  the  Souris  flows  through  it  in  a  gorge  350  feet 
deep.  From  this  vicinity  Hind  apjjlied  the  name  Blue  Hills  of  the  Som-is 
to  this  belt,  but  that  name  is  not  used  by  the  people  of  the  district. 

Riding  and  Duck  mountains. — North  of  the  Assiniboine  River  the  eastern 
outline  of  the  continuation  of  this  plateau  is  preserved  in  the  prominent 

'  From  the  aboriginal  name,  which   doubtless  refers  to  the  cougar  or  American  panther  {Felis 
concolor  L.). 


EIDING  AND  DUCK  MOUNTAINS.  43 

elevations  of  Riding  and  Duck  mountains,  two  remarkable  wooded  high- 
lands, much  alike  in  their  general  features  and  extent.  The  steep  eastern 
escarpment  of  each  is  about  50  miles  long,  that  of  Riding  Mountain 
trending  from  southeast  to  northwest  and  that  of  Duck  Mountain  having  a 
course  a  few  degrees  west  of  north.  These  elevations  rise  above  the  country- 
adjoining  the  Assiniboine  by  a  somewhat  gradual  slope,  but  they  are 
abruptly  cut  off  on  their  northeast  side  by  a  precipitous  descent.  This 
takes  place  on  a  line  approximately  parallel  with  Lakes  Manitoba  and 
Winnipegosis,  the  former  of  these  lakes  being  about  40  miles  east  of 
Riding  Mountain,  while  the  south  end  of  the  latter  is  25  miles  east 
of  Duck  Mountain.  The  crests  of  these  highlands,  according  to  Mr.  J.  B. 
Tyrrell's  measurements,  ai-e  respectively  about  2,000  and  2,300  to  2,700 
feet  above  the  sea,  the  latter  being  the  highest  land  in  Manitoba;  and  the 
-bases  of  their  escarpments  are  about  1,200  to  1,500  feet  above  the  sea,  being 
400  to  700  feet  above  the  lakes  on  the  east,  whose  height  slightly  exceeds 
800  feet. 

The  reader  is  refen-ed  to  Mr.  Tyrrell's  map  and  descriptions  of  the 
district  of  Riding  and  Duck  mountains  for  details  of  its  topography  and 
geology,  and  of  the  shore-lines  of  Lake  Agassiz  north  of  the  limit  of  my 
exploration.^ 

Porcupine  and  Pasquia  hills. — Beyond  Duck  Mountain,  after  an  inter- 
ruption of  about  30  miles  across  the  basins  of  Swan  and  Woody  rivers,  this 
line  of  highlands  is  continued  in  the  Porcupine  Mountain  or  hills,  which 
reach  about  25  miles  from  south  to  north.  These  form  a  somewhat  broken 
plateau,  similar  with  the  preceding  in  its  general  features  of  steep  acclivity 
on  the  east  and  gentle  descent  westward.  On  their  north  side  another  gap, 
about  20  miles  wide,  is  occupied  by  the  Red  Deer  and  Overflowing  rivers. 

Next  are  the  Pasquia  Hills,  whose  eastern  end  is  in  line  with  Pembina, 
Riding,  and  Duck  mountains  and  the  Porcupine  Hills,  being  about  100 
miles  west  from  the  mouth  of  the  Saskatchewan.  The  Pasquia  Hills  extend 
thence  150  miles  westward,  where  they  formed  the  southern  shore  of  the 
northwestern  arm  of   Lake  Agassiz,  lying  about  25   miles  south  of  the 

JGeol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  Ill,  for  1^87-88,  pp. 
1-16  E,  with  a  preliminary  contour  map.  Bulletin,  G.  S.  A.,  Vol.  1, 1890,  pp.  395-410.  Am.  Geologist, 
Vol.  VIII,  pp.  19-28,  July,  1891. 


44  THE  GLACIAL  LAKE  AGASSIZ. 

Saskatchewan  River  and  parallel  with  it  to  the  Birch  Hills  and  the  South 
Saskatchewan.  They  are  the  northern  escarpment  limiting  the  irregularly 
eroded  country,  which  is  here  considered  as  an  extension  of  the  great  plateau 
of  North  Dakota  and  southern  Manitoba  and  Assiniboia,  thus  holding  the 
same  relation  to  the  valley  of  the  Saskatchewan  that  the  Tiger  Hills 
sustain  to  the  Assiniboine  Valley. 

Great  Bear  Hills. — On  the  north  side  of  the  Saskatchewan  the  Great 
Bear  Sand  Hills,  extending  in  a  north-northwest  course  to  the  east  end  of 
Lac  la  Rouge  and  to  the  Churchill  River,  are  geographically  a  continuation 
of  the  line  of  highlands  thus  described  from  the  Coteau  des  Prairies  and 
Pembina  Mountain  to  the  Pasquia  Hills,  and  they  will  probably  be  found 
also  to  belong  to  the  same  geologic  age.  If  this  be  true,  they  differ  from 
this  great  Cretaceous  escarpment  south  of  the  Saskatchewan  by  being  out- 
lying remnants,  separated  from  the  broad  Cretaceous  area  on  the  west  by 
a  belt  of  Devonian  limestones  where  these  overlying  beds  have  been  eroded. 
The  amount  of  erosion  west  of  the  middle  portion  of  this  escarpment, 
through  North  Dakota  and  in  southern  Manitoba,  since  the  cycle  of  base- 
leveling  which  spared  the  Turtle  Mountain  area,  has  been  inconsiderable, 
so  that  in  general  the  surface  is  a  great  plain  with  a  gradual  ascent  west- 
ward. On  the  south  the  Cretaceous  strata  are  deeply  eroded  west  of  the 
Coteau  des  Prairies,  exposing  the  underlying  red  quartzite,  probably  of 
Keweenawan  age,  at  the  celebrated  Pipestone  quarry  in  southwestern  Min- 
nesota and  at  many  localities  thence  westerly  to  the  James  River.  Again, 
in  western  Manitoba  and  northwestward,  between  the  Assiniboine  and  Sas- 
katchewan rivers,  the  Cretaceous  strata  are  much  denuded,  though  not  worn 
through,  west  of  the  highlands  that  form  their  eastern  escarpment.  Still 
farther  north,  between  the  Saskatchewan  and  Churchill  rivers,  the  denuda- 
tion appears  to  have  cut  through  the  Cretaceous  beds  and  to  have  left 
remnants  of  their  eastern  portion. 

FOREST  AND   PRAIEIB. 

The  area  of  Lake  Agassiz  is  crossed  by  the  southwestern  boundary  of 
the  forest  that  overspreads  the  greater  part  of  British  America  and  nearly 
all  of  the  eastern  half  of  the  United  States.     This  boundary  between  forest 


BOUNDAEY  BETWEEN  FOREST  AND  PEAIRIE.         45 

and  prairie  (see  PI.  XXXVIII,  Chapter  XI),  having  an  almost  wholly  tim- 
bered region  on  its  northeast  side,  and  a  region  on  its  southwest  side  that 
is  chiefly  grass  land,  without  trees  or  shrubs,  excepting  in  narrow  belts 
along  the  streams  and  occasional  groves  beside  lakes,  runs  as  follows :  From 
near  the  junction  of  the  South  and  North  Saskatchewan  rivers  it  passes 
southeasterly  by  the  sources  of  the  Red  Deer  and  Assiniboine  rivers  and 
over  the  southwestern  slopes  of  Duck  and  Riding  mountains  to  the  south 
end  of  Lakes  Manitoba  and  Winnipeg.  Thence  it  turns  southward  and 
holds  this  course  along  the  east  side  of  the  Red  River  and  approximately 
parallel  with  it,  at  a  distance  increasing  from  15  to  50  miles  from  the  river 
for  about  300  miles  to  the  upper  part  of  this  stream,  where  it  flows  from 
.east  to  west.  It  enters  the  United  States  about  15  miles  east  of  Emerson 
and  St.  Vincent  and  extends  south-southeastward  to  the  mouth  of  Thief 
River,  the  sources  of  Poplar  and  Sand  Hill  rivers,  and  the  White  Earth 
Agency,  being  at  the  last-named  locality  some  60  miles  distant  from  the 
Red  River.  Its  course  continues  to  the  south  by  Detroit  and  Pelican  Rapids 
to  Fergus  Falls,  where  it  crosses  the  Red  River,  and  thence  it  runs  south 
east  and  east  through  the  central  part  of  the  south  half  of  Minnesota. 

Grroves  border  the.  greater  part  of  Lakes  Big  Stone  and  Traverse,  and 
cover  the  islands  of  Big  Stone  Lake.  But  considerable  portions  of  the 
shores  and  bluffs  of  these  lakes  and  the  islands  of  Lake  Traverse  are 
destitute  of  timber,  or  bear  only  bushes  and  small  trees.  The  Bois  des 
Sioux  River  has  no  timber  along  the  upper  two-thirds  of  its  course,  but 
below  is  fringed  here  and  there  by  woods,  from  which  it  derives  its  name. 
The  Mustinka  River,  flowing  into  the  north  end  of  Lake  Traverse;  Rabbit 
River,  tributary  to  the  Bois  des  Sioux;  and  the  upper  part  of  Wild  Rice 
River,  in  North  Dakota,  and  of  Elm  River,  tributaries  of  the  Red  River, 
are  also  unwooded. 

The  Red  River  has  no  timber,  or  very  little,  for  20  miles  east  from  its 
bend  at  Breckenridge  and  Wahpeton.  In  the  next  10  miles  downstream  it 
has  scattered  groves  of  bur  oak,  ash,  box  elder,  elm,  and  basswood,  occupy- 
ing perhaps  one-fourth  of  this  distance,  while  small  poplars  and  willows 
occasionally  appear  in  the  spaces  between  the  groves.  Thence  to  the  north 
this  river  is  continuously  fringed  with  timber,   and  its  larger  tributaries 


4fi  THE  GLACIAL  LAKE  AGASSIZ. 

have  their  course  marked  in  the  same  way.  The  growth  of  wood  is  here 
confined  chiefly  to  the  banks  of  the  streams,  which  have  cut  hollows  20  to 
40  feet  deep  in  the  broad  lacustrine  plain. 

About  a  sixth  part  of  the  area  of  Lake  Agassiz,  and  a  larger  propor- 
tion (nearly  the  whole)  of  the  adjoining  country  on  the  south  and  west, 
are  prairie,  this  term  being  commonly  used  to  embrace  all  tracts  destitute 
of  trees  and  shrubs,  but  well  covered  with  grass.  Groves  of  a  few  acres, 
or  sometimes  a  hundred  acres  or  more,  occur  here  and  there  upon  this 
prairie  region  beside  lakes,  and  a  narrow  line  of  timber  usually  borders 
streams,  as  just  described  along  the  Red  River;  but  many  lakes  and  creeks, 
and  even  portions  of  the  course  of  large  streams,  have  neither  bush  nor 
tree  in  sight,  and  occasionally  none  is  visible  in  a  view  which  ranges  from 
5  to  10  miles  in  all  directions.  The  contour  of  the  prairie  is  as  varied  as 
that  of  the  wooded  region.  Within  the  area  of  Lake  Agassiz  the  surface 
is  almost  absolutely  level,  but  the  adjoining  prairie  country  is  undiilating, 
rolling,  and  hilly,  haAang  in  some  tracts  a  very  rough  surface  of  knolls, 
hills,  and  ridges  of  morainic  drift  that  rise  steeply  25  to  100  feet  or  more 
above  the  intervening  hollows.  The  material  of  the  greater  part  of  all 
these  areas,  whether  forest  or  prairie,  is  closely  alike,  being  till  or  unmodi- 
fied glacial  drift,  showing  no  important  diff"erences  such  as  might  cause  the 
growth  of  forest  in  one  region  and  of  only  grass  and  herbage  in  another. 
Chapter  XI  will  include  a  discussion  of  the  climatic  conditions,  as  abun- 
dance or  lack  of  rainfall,  and  auxiliary  causes,  as  prairie  fires,  by  which  the 
limits  of  these  diverse  phases  of  veg'etation  have  been  determined. 

EXISTING    LAKES    WITHIN    THE  AREA    OF    LAKE  AGASSIZ. 

The  glacial  Lake  Agassiz  was  gradually  reduced  in  size,  first  by  the 
lowering-  of  its  southward  outlet,  and  afterwards  by  finding  successively 
lower  outlets  to  the  northeast,  until,  with  the  complete  departure  of  the  ice- 
sheet,  it  shi'ank  to  its  present  representatives,  the  great  lakes  of  Manitoba. 
These  are  three  in  number.  Lakes  Winnipeg,  Manitoba,  and  Winnipegosis. 
With  them  are  associated  several  others,  comparatively  small,  as  Cedar 
Lake,    through    which    the    Saskatchewan  -flows   near    its    mouth;    Lake 


LAKE  WINNIPEG.  47 

Dauphin,  south  of  Lake  Winnipegosis  and  ti'ibutaiy  to  it ;  and  Lake  St. 
Martin,  on  the  Fairford  or  Little  Saskatchewan  River,  the  outlet  of  Lakes 
Manitoba  and  Winnipegosis. 

Many  other  lakes  of  still  smaller  size,  but  ranging  up  to  several  miles 
in  extent,  are  scattered  here  and  there  on  all  this  northern  ^^art  of  the  bed 
of  Lake  Agassiz.  Such  small  lakes  are  also  frequent  on  its  southeastern 
part,  in  northern  Minnesota,  eastward  from  Roseau,  Thief,  Mud,  and  Maple 
lakes,  besides  the  three  large  lakes  of  that  district,  Rainy  Lake,  the  Lake  of 
the  Woods,  and  Red  Lake. 

Lake  Winnipeg. — The  length  of  Lake  Winnipeg  is  about  250  miles, 
trending  from  south-southeast  to  north-northwest,  while  the  maximum 
width  of  its  southern  part  is  about  25  miles,  and  of  its  northern  part  60 
miles.  Its  area  is  approximately  8,500  square  miles,  being  intermediate  in 
extent  between  Lakes  Ontario  and  Erie.  Eighty-five  miles  from  its  south 
end,  Lake  Winnipeg  is  reduced  to  a  strait  2  to  4  miles  wide,  which  extends 
northwesterly  12  miles,  terminating  at  the  cape  called  Dog  Head.  The 
narrowest  part  of  the  strait,  scarcely  exceeding  a  mile  in  width,  is  at  this 
cape.  Here  the  strait  opens  into  the  northern  and  main  portion  of  the 
lake,  which  includes  five-sixths  of  its  area. 

The  elevation  of  Lake  Winnipeg,  determined  by  the  survey  for  the 
Canadian  Pacific  Railway,  is  710  feet  above  the  sea.  Its  depth,  according 
to  Mr.  J.  Hoyes  Panton,  nowhere  exceeds  65  feet.  "The  shallowness  of 
this  comparatively  large  body  of  water,"  as  Mr.  Panton  writes,  "accounts 
for  its  treacherous  nature,  and  explains  how  on  many  occasions  it  has 
proved  a  disastrous  waterway  to  the  freighting-  boats  of  bygone  days.  As 
you  sit  upon  the  deck  of  the  steamer,  threading  its  way  among  the  islands, 
you  are  surprised  at  the  tortuous  course  made,  when  water  seems  on  every 
side  and  no  shore  near.  So  shallow  is  the  lake  that  many  places  miles 
from  land  are  not  covered  with  more  than  6  or  7  feet  of  water.  It  is  only 
safe  to  experienced  captains,  thoroughly  acquainted  with  the  concealed 
channels  that  afford  a  safe  course  at  a  distance  from  the  shore."  ^  On 
account  of  this  slight  depth,  the  water  of  most  parts  of  the  lake  is  com- 

i"  Notes  on  the  geology  of  some  islands  in  Lake  Winnipeg."     Transactions  of  the  Historical  and 
Scientific  Society  of  Manitoba,  January  28, 1886. 


48  •        THE  GLACIAL  LAKE  AGASSIZ. 

monly  turbid  with  mud,  stirred  up  by  the  waves  from  its  shores  and  bed.^ 
Low  land  borders  this  lake  along  nearly  its  whole  extent,  and  the  highest 
points  on  the  shore  or  visible  from  it  rarely  attain  an  elevation  of  50  feet. 

Lakes  Manitoba  and  Winnipegosis. — Lake  Manitoba^  lies  about  40  miles 
west  of  the  south  half  of  Lake  Winnipeg;  and  Lake  Winnipegosis,^  sepa- 
rated only  about  2  miles  from  the  north  end  of  Lake  Manitoba,  lies  mostly 
40  to  50  miles  west  of  the  north  half  of  Lake  Winnipeg,  but  its  most 
northeast  part  is  only  20  miles  southwest  from  that  lake.  The  length  of 
each  of  these  lakes,  measured  in  a  straight  line,  is  about  120  miles,  trend- 
ing in  parallelism  with  Lake  Winnipeg,  from  south-southeast  to  north- 
northwest;  and  each  of  them  covers  an  area  of  nearly  2,000  square  miles. 
Both  are  shallow  in  proportion  to  their  size,  and  are  surrounded  by  low  ■ 
shores. 

The  maximum  width  of  Lake  Manitoba,  about  28  miles,  is  at  its  south 
end.  Near  its  middle  it  is  narrowed  to  a  strait  about  a  half  mile  wide  and 
2  miles  long.  Its  northern  part  is  of  quite  irregular  form,  and  is  nearly 
intersected  from  the  north  by  a  long  peninsula.  This  lake,  according  to 
leveling  by  Mr.  H.  S.  Treherne,  is  809  feet  above  the  sea,  being  thus 
almost  exactly  100  feet  higher  than  Lake  Winnipeg,  to  which  it  is  tributary 
by  the  Little  Saskatchewan.  The  country  between  these  lakes  and  from 
Lake  Manitoba  west  to  Lake  Dauphin  and  to  Riding  and  Duck  mountains 
is  low  and  approximately  level,  but  has  a  general  westward  ascent,  aver- 
aging a  few  feet  per  mile. 

The  width  of  Lake  Winnipegosis  varies  from  5  to  15  miles.  Its 
northern  portion  is  bent  to  the  west  and  south,  terminating  in  Dawson 
Bay,  so  that  its  length,  following  this  course,  is  nearly  150  miles.  Its 
outlines,  moreover,  are  very  irregular,  presenting   a  constantly  varying 

'"Lake  Winnipeek  receives  its  uame  from  the  muddy  or  sallow  appearance  of  its  waters;  We 
signifies  muddy,  and  Nepe  water,  in  Chippewa." — Keating's  Narrative  of  Long's  Expedition,  Vol.  II, 
p.  77. 

-Meaning  the  "Narrows  or  Strait  of  the  Manitou  or  Great  Spirit,"  as  I  am  informed  by  letters 
from  Prof.  George  Bryce  and  Mr.  J.  B.  Tyrrell.  This  name  was  originally  pronounced  by  white  inhab- 
itants nearly  as  by  the  Indians,  with  accents  on  the  initial  and  final  syllables;  but  during  the  past 
ten  years  or  more  its  almost  universal  pronunciation  in  English  has  been  with  only  one  accent,  which 
is  laid  on  the  next  to  the  last  syllable. 

'Meaning  "Little  Winnipeg." — Hind's  Narrative  of  the  Canadian  Exploring  Expeditions,  Vol. 
11,  p.  42. 


RAINY  LAKE  AND  THE  LAKE  OF  THE  WOODS.        49 

succession  of  bays,  capes,  and  islands.  This  lake  outflows  by  Water  Hen 
Lake  and  River  to  Lake  Manitoba,  and  has  an  elevation  of  19  feet  above 
the  latter,  as  determined  by  surveys  for  the  Canadian  Pacific  Railway,  or 
828  feet  above  the  sea. 

Rainy  Lake. — Two  bodies  of  water  of  considerable  size,  namely.  Rainy 
Lake  and  the  Lake  of  the  Woods  (PI.  XI),  lie  on  the  northern  boundary 
of  Minnesota,  within  the  eastern  part  of  the  area  of  Lake  Agassiz.  The 
length  of  Rainy  Lake  is  slightly  more  than  50  miles,  trending  from  east- 
southeast  to  west-northwest,  and  its  average  width  is  about  5  miles,  giving 
it  an  area  of  250  square  miles,  approximately.  It  is  extremely  diversified 
by  projecting  points,  numerous  bays  and  narrow  arms,  and  plentiful  islands. 
Its  height  above  the  sea  is  about  1,117  feet,  and  its  maximum  depth, 
according  to  soundings  by  Dr.  A.  C.  Lawson,  is  110  feet. 

Lake  of  the  Woods. — The  Lake  of  the  Woods  has  a  very  irregular 
form,  nearly  surrounding  a  large  peninsula  in  its  northern  part,  and 
including  many  bays  on  the  north  and  east,  some  of  them  connected  with 
the  main  lake  only  by  narrow  channels.  A  multitude  of  islands,  large  and 
small,  dot  its  surface,  excepting  in  its  southwest  part,  called  Sand  Hill 
Lake,  where  it  adjoins  Minnesota.  Measured  from  north  to  south  or  from 
east  to  west,  its  maximum  extent  in  either  direction  is  60  miles  approxi- 
mately, and  its  area  is  about  1,500  square  miles.  Its  elevation,  determined 
by  the  Canadian  Pacific  Railway  survey,  is  1,060  feet  above  the  sea,  and 
the  maximum  depth  of  its  northern  part,  called  Clear  Water  Lake,  is  stated 
by  Dr.  G.  M.  Dawson  to  be  84  feet. 

Bed  Lake. — The  largest  lake  lying  wholly  in  Minnesota  is  Red  Lake 
(PI.  XII),  situated  in  the  southeast  edge  of  the  area  of  Lake  Agassiz,  at  a 
distance  of  about  50  miles  south  from  the  Lake  of  the  Woods.  Its  eleva- 
tion, as  determined  by  the  Duluth  and  Winnipeg  Railroad  survey,  is  1,172 
feet  above  the  sea,  being  about  40  feet  below  the  adjacent  portion  of  the 
highest  shore-line  of  the  glacial  lake.  A  strait  about  three-fourths  of  a. 
mile  wide  divides  Red  Lake  into  two  nearly  equal  parts,  which  trend  from 
east  to  west.  The  length  of  each  part  is  somewhat  more  than  20  miles, 
and  of  both  together  about  30  miles,  while  the  maximum  width  of  each  is 
about  10  miles.  Its  area  is  approximately  440  square  miles.  This  lake 
MON   XXV 4 


50  THE  GLACIAL  LAKE  AGASSIZ. 

differs  remarkably  from  all  the  preceding  in  its  regular  outlines,  broken  by 
no  capes  nor  bays,  and  in  the  complete  absence  of  islands.  The  map  plate 
shows  the  various  di-ift  deposits  adjoining  Red  Lake,  as  observed  in  a  canoe 
trip  along  its  entire  shore-line  in  September,  1885. 

RIVERS  TRIBUTARY  TO   LAKE   AGASSIZ   AND  DRAINING  ITS  AREA. 

The  area  of  Lake  Agassiz  is  drained  to  Lake  Winnipeg  chiefly  by  the 
Winnipeg,  Red,  and  Little  Saskatchewan  (or  Fairford)  rivers.  On  the  north- 
west this  glacial  lake  also  included  the  region  crossed  by  the  lower  part  of 
the  Saskatchewan.  Flowing  out  from  Lake  Winnipeg,  the  united  waters 
of  all  these  river  .systems  are  carried  by  the  Nelson  to  Hudson  Bay. 
PI.  XIII  is  colored  to  show  the  several  drainage  areas  of  the  Lake  Agassiz 
basin  and  adjoining  country. 

Rainy  and  Winnipeg  rivers. — It  seems  probable  that  the  recession  of 
the  ice-sheet  uncovered  the  entire  course  of  the  Rainy  and  Winnipeg  rivers 
before  Lake  Agassiz  had  fallen  below  the  level  of  Rainy  Lake.  These  are 
upper  and  lower  portions  of  the  main  trunk  of  the  same  I'iver  system. 
East  of  Rainy  Lake  a  large  tract  tributary  to  it  reaches  nearly  a  hundred 
miles  on  the  international  boundary,  including  ahnost  countless  lakes  and 
small  streams. 

Rainy  River,  about  80  miles  long,  connecting  Rainy  I^ake  and  the 
Lake  of  the  Woods,  is  a  broad  and  majestic,  deep  stream,  with  an  average 
width  of  a  sixth  of  a  mile,  flowing  in  general  in  a  somewhat  direct  west- 
northwest  course.  At  the  mouth  of  Rainy  Lake  it  has  rapids  that  fall 
about  3  feet.  Its  principal  falls  are  between  Koochiching  and  Fort  Frances, 
situated  opposite  to  each  other  on  the  south  and  north  banks  of  the  river, 
a  little  more  than  2  miles  from  Rainy  Lake,  where  it  descends  23  feet  in 
about  a  tenth  of  a  mile.  Manitou  Rapids,  about  35  miles  from  Rainy 
Lake,  are  a  short  descent  of  about  2  feet,  with  outcropping  rock  in  the 
channel  and  banks.  Six  miles  below  these  is  the  Long  Sault,  a  mile  in 
length,  estimated  by  Major  Long  to  have  "an  aggregate  descent  of  about 
10  feet;"^  but  subsequent  leveling  by  S.  J.  Dawson  shows  that  it  probably 

iKeating's  Narrative  of  Long's  Expedition,  Vol.  II,  p.  230. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XII- 


Mos^       Tamarack      Su 
i ^°'o. 


R.36 


T.  146 


MAP    OF  RED    LAKE    AND    ITS   VICINITV. 


us  HI  Ex  a  CO  f 


Scale,  6    miles    lo  an   incli. 


EAINY  AND  WINNIPEG  EI  VERS.  51 

does  not  exceed  two-thirds  this  amount.  Excepting  these  rapids,  Rainy 
River  has  an  average  descent  of  only  about  3  inches  per  mile,  giving  to  the 
ordinary  low  stage  of  water  a  very  gentle  current.  It  is  navigable  for  large 
steamboats  from  the  Lake  of  the  Woods  to  the  foot  of  the  Long  Sault, 
and  thence  to  Rainy  Lake  it  is  navigated  by  a  tug  or  propeller,  towing 
Mackinaw  boats.  The  banks  of  the  river  are  only  10  to  20  feet  high,  and 
are  fertile  and  heavily  wooded,  having  commonly  a  clayey  soil.  The  most 
important  tributaries  of  Rainy  River  are  on  its  south  side,  and  include  the 
Little  I  ork  and  the  Big  Fork  or  Bowstring  River  (whose  mouths  are 
respectively  about  15  and  21  miles  from  Rainy  Lake),  Black  River  (4  miles 
below  the  Big  Fork),  and  the  Rapids  or  Winter  Road  River  (about  12  miles 
from  the  Lake  of  the  Woods). 

Winnipeg  River,  the  outlet  of  the  Lake  of  the  Woods,  has  a  length  of 
about  160  miles,  flowing  in  a  winding  course  to  the  northwest.  Its  total 
descent  is  350  feet,  four-fifths  of  this  being  in  the  many  falls  and  rapids 
which  occur  along  nearly  its  entire  extent.  These  falls  are  divided  by 
portions  with  only  a  strong  or  gentle  current,  or  by  lake-like  expansions  of 
the  river  where  no  current  is  perceptible.  At  Rat  Portage  the  Winnipeg 
flows  out  from  the  Lake  of  the  Woods  by  two  channels,  which  are  divided 
by  Tunnel  Island.  Each  channel  descends  about  16  feet,  the  eastern  one 
being  called  Hebes  Falls,  and  the  western  one  the  Witches  Caldron,  which 
opens  into  Winnipeg  or  Darlington  Bay.  After  flowing  about  8  miles 
through  this  and  other  bays  or  lakes,  the  river  enters  the  Dalles,  passing 
with  a  very  swift  current  between  perpendicular  walls  of  granite.  Beyond 
the  Dalles  its  banks  and  abundant  islands  along  a  distance  of  about  15 
miles,  as  described  by  Keating,  are  clay  slate,  occasionally  varying  to  mica- 
schist.  "The  river  expands  considerably,  being  in  some  places  several 
miles  wide.  *  *  *  Its  cun-ent  is  swift,  especially  near  the  islands,  but 
it  is  free  from  i-ipples;  we  observed  none  of  the  foaming  rapids  which 
characterize  the  lower  part  of  the  stream.  The  islands,  which  in  some 
places  are  countless,  are  generally  small  and  of  a  form  nearly  square;  from 
the  vertical  stratification  of  the  rock  their  banks  are  perpendicular;  they 
generally  rise  from  10  to  20  feet  above  the  level  of  the  water."  Below  this 
belt  of  slate  the  river  flows  through  a  very  picturesque  region  of  granite, 


52  THE  GLACIAL  LAKE  AGASSIZ. 

gneiss,  and  schists,  over  many  falls,  cascades,  and  rapids,  and  tkrough 
numerous  lakes.  In  descending  order  these  include  Jacks  Falls,  the  Upper 
Falls,  "which  for  beauty  are  second  only  to  the  Lower  Falls;"  Slave  Falls, 
"computed  at  20  feet;"  Lac  du  Bonnet,  "about  15  miles  long  and  from 
600  yards  to  4  miles  in  breadth,"  and  the  Lower  Falls.^ 

On  each  side  the  country  rises  to  a  moderate  elevation  in  low  hills  and 
ridges,  with  frequent  outcrops  of  the  bed-rocks.  The  highest  land  crossed 
by  the  Canadian  Pacific  Railway  south  of  the  Winnipeg  River,  from  18  to 
28  miles  west  of  Rat  Portage,  is  about  200  feet  above  the  Lake  of  the 
Woods  and  about  550  feet  above  Lake  Winnipeg,  rising  thus  nearly  to  the 
highest  level  of  Lake  Agassiz.  English  River,  which  flows  through  Lac 
Seul,  or  Lonely  Lake,  is  a  large  tributary  of  the  Winnipeg  from  the  east. 
The  only  important  affluent  from  the  south  is  the  Whitemouth  River,  drain- 
ing a  considerable  area  west  of  the  Lake  of  the  Woods.  The  water  of 
Winnipeg  River  is  very  clear,  and  is  strongly  contrasted  with  the  muddy 
water  of  Lake  Winnipeg,  with  which  it  mingles  at  its  mouth. 

Red  Lake  River. — Originally  the  name  Red  River  was  apphed  by  the 
Indians  to  the  outlet  of  Red  Lake,  flowing  westerly  to  Grand  Forks  and 
thence  northerly  to  Lake  Winnipeg,  and  the  sti-eam  now  called  Red  River 
was  known  to  them  as  the  Ottertail  River  from  Ottertail  Lake  to  its  junc- 
tion with  the  Red  Lake  River.  Belfcrami  affirms,  with  poetic  license,  that 
the  aboriginal  names  of  Red  Lake  and  of  its  outflowing  river,  the  latter 
translated  by  him  Bloody  River,  refer  to  the  "blood  of  the  slain"  in  the 
wars  between  the  Ojibways  and  Dakotas.-     This  stream  is  the  largest  trib- 

'Keating's  Narrative  of  Long's  Expedition,  Vol.  II,  pp.  82-102. 

■^A  Pilgrimage  in  Europe  and  America,  leading  to  the  discovery  of  the  sources  of  the  Mississippi 
and  Bloody  River,  Vol.  II-,  pp.  335-340.  Also  see  Keating's  Narrative  of  Long's  Expedition,  Vol. 
II,  p.  34. 

Rev.  J.  A.  Gilfillan,  however,  states  that  the  Ojibway  name  of  Red  Lake  perhaps  alludes  to 
"  reddish,  fine  gravel  or  sand  along  the  shore  in  places,  which  in  storms  gets  wrought  into  the  v/ater 
near  the  edges,''  or  to  the  reddish  color  of  streams  flowing  into  the  lake  from  bogs  on  its  north  side. 
(Fifteenth  Annual  Report,  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  for  1886,  p.  460.) 

D.  D.  Owen,  in  the  description  of  his  canoe  journey  down  the  Red  River,  writes  of  its  junction 
with  the«Red  Lake  River  at  Grand  Forks:  "The  Red  Fork  of  Red  River,  which  flows  from  Red  Lake, 
*  *  *  is  the  stream  to  which  the  name  of  Red  River  properly  belongs.  The  stream  ■which  we 
navigated  is  known  to  the  Indians  by  the  name  of  Ottertail  River.  The  color  of  the  waters  of  Red 
River  proper  also  shows  the  origin  of  the  name.  They  are  of  a  reddish  brown  cast,  and  contrast 
strongly  with  the  whitish,  milky  appearance  of  the  stream  coming  from  Ottertail  Lake,  and  which 
henceforth  assumes  a  darker  hue." — Report  of  a  Geological  Survey  of  Wisconsin,  Iowa,  and  Minne- 
sota, 1852,  pp.  176,  177. 


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EED  LAKE  EIVER  AND  THE  GRAND  MARAIS.         53 

utary  of  the  Red  River  from  its  east  side.  From  Red  Lake  to  the  mouth 
of  Thief  River  it  flows  west-northwest  about  40  miles,  measured  in  a  direct 
line;  next  it  flows  south  16  miles  to  a  point  about  3  miles  east  of  Red  Lake 
Falls;  thence  west-southwest  21  miles  to  Crookstou,  and  finally  west  and 
northwest  23  miles  to  Grand  Forks.  Its  entire  length,  not  measuring 
minor  bends,  is  thus  approximately  100  miles,  but  if  the  course  of  the  river 
were  followed  in  all  its  meanderings  this  distance  would  be  nearly  doubled. 
Its  width  varies  mostly  from  6  to  10  rods.  At  its  mouth  it  has  only  about 
half  as  great  width  as  the  Red  River  above  their  junction,  but  probably 
can-ies  an  equal  volume  of  water,  as  it  flows  with  a  much  stronger  current, 
estimated  between  2  and  3  miles  per  hour  at  the  stage  of  ordinary  low 
water. 

The  Grand  Marais,  extending  22  miles  from  the  Red  Lake  River  near 
Fisher  to  a  point  on  the  Red  River  12  miles  below  Grand  Forks,  is  a  former 
channel  of  the  Red  Lake  River,  now  occupied  by  marshes,  pools,  and  lake- 
lets. The  width  of  this,  deserted  chamiel  or  valley,  measured  between  the 
crests  of  its  bluff's,  varies  commonly  from  15  to  30  rods,  rarely  expanding  to 
a»quarter  or  third  of  a  mile,  and  its  depth  below  the  general  level  of  the 
valley  plain  is  mostly  about  20  feet.  It  is  only  half  as  deep,  and  averages 
probably  not  more  than  a  fifth  as  wide,  as  the  present  river  valley.  During 
times  of  abundant  rains,  and  especially  when  the  snow  melts  in  the  spring 
a  stream  occupies  the  Grand  Marais,  but  through  the  greater  part  of  the 
year  it  has  no  running  water.  In  a  similar  manner  the  Wild  Rice  River  of 
Minnesota,  along  its  lower  portion,  at  first  flowed  in  the  present  channel  or 
valley  of  the  Marsh  River,  from  which  it  has  turned  away  about  2  miles 
southeast  of  Ada  to  a  more  southerly  course.  Doubtless  in  each  case  a 
smaller  stream  had  previously  begun  the  erosion  of  the  channel  into  which 
the  river  was  diverted. 

The  fall  of  Red  Lake  River  between  Red  Lake  and  Thief  River  is 
73  feet,  from  l.,172  to  1,099  feet  above  the  sea.  Thence  to  its  mouth  it 
descends  315  feet,  averaging  more  than  5  feet  per  mile  in  its  direct  course. 
Its  banks  and  bed  consist  of  glacial  drift,  excepting  where  this  formation 
is  covered  by  alluvial  deposits,  and  consequently  the  stream  has  acquired 
a  somewhat  regular  slope,  broken,  indeed,  by  frequent  rapids  where  it  runs 


54  THE  GLACIAL  LAKE  AGASSIZ. 

over  cobbles  and  bowlders,  but  having  no  abrupt  falls.  The  height  of  the 
banks  and  of  the  adjoining  country,  which  has  a  flat  or  slightly  undulating 
contour,  is  generally  30  to  40  feet  above  the  river;  but  in  the  vicinity  of 
Red  Lake  Falls  this  stream  and  the  Clear  Water  River,  an  important  tribu- 
tary to  it  from  the  southeast,  have  eroded  their  channels  to  the  depth  of 
nearly  100  feet.  The  range  of  these  rivers  from  low  to  high  water  at  Red 
Lake  Falls  is  only  5  feet,  and  the  descent  of  each  is  about  40  feet  within 

2  miles. 

Bed  River. — The  Red  River  of  the  North,  so  named  to  distinguish  it 
from  the  Red  River  of  Louisiana,  has  its  source  in  a  small  lake  about  1,550 
feet  above  the  sea,  13  miles  west  of  Lake  Itasca.  It  first  flows  south  about 
60  miles,  measured  in  a  direct  line,  passing  in  succession  through  Elbow, 
Many  Point,  Round,  Height  of  Land,  Little  Pine,  Pine,  and  Rush  lakes 
to  Ottertail  Lake,  this  portion  being  commonly  called  Ottertail  River.  In 
this  distance  it  descends  to  1,315  feet  above  the  sea.  The  contour  of  the 
adjoining  country  is  rolling  or  hilly  northward  ^nd  undulating  or  flat 
southward. 

Below  Ottertail  Lake  this  stream  is  called  the  Red  River  by  this 
report,  following  the  example  of  Owen  and  the  prevailing  popular  usage; 
but  it  is  still  occasionally  spoken  of  as  Ottertail  River  to  its  junction  with 
the  Bois  des  Sioux  River  at  Bi'eckenridge  and  Wahpeton,  42  miles  west  of 
Ottertail  Lake.^  The  descent  in  this  distance  is  372  feet,  or  about  5  feet 
per  mile,  following  the  course  of  the  stream.  It  is  most  rapid  in  the 
vicinity  of  Fergus  Falls,  amounting  to  80  feet  in  3  miles,  from  1,210  to 
1,130  feet  above  the  sea.  Because  of  the  numerous  large  lakes  on  the 
upper  part  of  the  stream,  its  volume  along  this  descent  to  Breckem-idge  is 
not  greatly  aff'ected  by  either  heavy  rains  and  snow  melting  or  dry  seasons. 
At  Fergus  Falls  the  range  from  its  lowest  to  its  highest  stage  is  only  2  or 

3  feet.  Its  banks  and  bed  are  the  hard,  stony  clay  of  the  glacial  drift, 
affording  a  good  foundation  for  dams  and  canals.  From  Ottertail  Lake 
to  the  border  of  Lake  Agassiz,  9  miles  southwest  from  Fergus  Falls,  the 

'The  Ojibways,  according  to  Rev.  J.  A.  Gilfillan  (1.  c,  p.  463),  thus  apply  the  name  Ottertail 
River  as  far  as  to  the  Bois  des  Sioux;  and  the  Red  River  thence  northward  is  called  by  them  Kitchi- 
zibi  (Great  River). 


THE  RED  RIVEE.  55 

country  is  rolling  and  hilly,  rising  50  to  100  feet  above  the  river.  Farther 
west  the  flat  or  slightly  undulating  surface  of  the  lacustrine  area  soon  sinks, 
so  that  the  average  height  varies  from  5  to  15  feet  above  the  river  in  its 
ordinary  low  stage,  yet  its  banks  are  seldom  or  never  ovei-flowed.  The  only 
noteworthy  ti-ibutary  to  the  Red  River  between  Ottertail  Lake  and  Breck- 
enridge  is  the  Pelican  River,  which  joins  it  from  the  north  3  miles  west  of 
Fergus  Falls.  This  stream,  nearly  50  miles  long  in  a  straight  line,  flows 
through  a  rolling  and  hilly  region,  receiving  the  waters  of  many  lakes,  of 
which  the  largest  are  Detroit,  Cormorant,  Pelican,  Lizzie,  and  Lida. 

From  its  bend  at  Breckenridge  and  Wahpeton  the  Red  River  flows 
north  285  miles,  measured  in  a  direct  line,  to  Lake  Winnipeg.  Its  course 
through  this  distance  has  been  already  described  in  an  earlier  portion  of 
this  chapter,  treating  of  the  Red  River  Valley.  The  entire  length  of  the 
Red  River,  measured  thus  in  straight  lines  successively  to  the  south,  west, 
and  north,  is  about  390  miles;  but  in  its  meanderings,  nowhere  diverging 
far  from  these  lines,  it  flows  nearly  700  miles.  Its  descent  below  Brecken- 
ridge is  233  feet,  and  in  total  from  its  source  to  its  mouth  approximately 
840  feet.  All  the  way  below  McCauleyville  and  Fort  Abercrombie,  15 
miles  north  of  Breckenridge,  it  is  navigated  by  steamboats,  barges,  and 
flatboats,  but  along  the  Goose  Rapids,  extending  about  12  miles  next  below 
the  mouth  of  Goose  River  as  measured  in  the  meandering  course  of  the 
stream,  the  channel  is  obstructed  by  bowlders  which  forbid  navigation 
during  low  stages  of  water.  A  broad  belt  of  till,  formed  by  the  united 
Fergus  Falls  and  Leaf  Hills  moraines,  as  described  in  Chapter  IV,  causes 
these  rapids.  The  width  of  this  river  in  the  United  States  varies  from  6  to 
20  rods,  being  in  some  places  less  than  the  length  of  the  steamboats;  but 
north  of  the  international  boundary  it  is  commonly  20  rods  wide. 

The  range  between  the  lowest  and  highest  stages  of  the  Red  River 
increases  rapidly  north  of  Breckenridge,  becoming  32  feet  at  Moorhead  and 
Fargo,  and  attaining  its  maximum  of  50  feet  at  Belmont.  It  continues 
nearly  at  40  feet  from  Grand  Forks  to  the  international  boundary  and  to 
Winnipeg.  At  Lower  Fort  Garry,  16  miles  north  of  Winnipeg  and  about 
20  miles  from  the  mouth  of  the  river,  it  is  35  feet;  but  beyond  that  point  it 
rapidly  diminishes  in  approaching  Lake  Winnipeg.     Floods  rising  nearly  or 


56  THE  GLACIAL  LAKE  AGASSIZ. 

quite  to  the  high- water  line  thus  noted  have  been  rare,  occurring  in  1826, 
1852,  1860,  1861,  and  1882.  They  are  caused  in  the  spring  by  the  melting 
of  unusual  supplies  of  snow  and  by  accompanying  heavy  rains,  and  often 
are  increased  by  gorges  of  ice,  which  is  usually  broken  up  along  the 
southern  upper  portion  of  the  river  earlier  than  along  its  lower  course. 
These  floods  attain  a  height  only  a  few  feet  below  the  level  of  the  adjoining 
prauie  where  that  is  highest,  and  along  the  greater  part  of  the  distance 
between  Grand  Forks  and  Lower  Fort  Garry  the  banks  are  overflowed 
and  the  flat  land  on  each  side  of  the  river  to  a  distance  of  2  to  4  or  5  miles 
from  it  is  covered  with  water  1  to  5  feet  or  more  in  depth. 

The  noteworthy  tributaries  of  the  Red  River  on  its  east  side,  in  their 
order  from  south  to  north,  are  the  Buffalo,  Wild  Rice,  Marsh,  Sand  Hill, 
Red  Lake,  Snake,  and  Tamarack  rivers,  the  stream  named  Two  Rivers  for 
its  two  branches  which  unite  3  miles  above  its  mouth,  and  Joe,  Roseau, 
and  Rat  rivers;  and  on  the  west,  the  Bois  des  Sioux,  Wild  Rice,  Sheyenne, 
Elm,  Goose,  Turtle,  Forest,  Park,  Pembina,  Marais,  Scratching  or  Boyne, 
La  Salle,  and  Assiniboine  rivers.  Excepting  the  Red  Lake  River,  ah-eady 
described,  and  the  Sheyenne,  Pembina,  and  Assiniboine  rivers,  all  these  are 
small,  the  farthest  portions  of  their  areas  of  di-ainage  being  40  to  75  miles 
from  the  Red  River.  In  summer  droughts  several  of  them,  including  the 
Bois  des  Sioux,  are  dried  up  along  the  greater  part  of  their  course,  contain- 
ing only  here  and  tliere  pools  in  the  deeper  hollows  of  the  channel. 

Sheyenne  Biver.—T\\e  Sheyenne,  having  its  sources  near  the  great 
southeastern  bend  of  the  Souris  or  Mouse  River,  in  North  Dakota,  first 
flows  to  the  east  nearly  100  miles,  passing  10  miles  south  of  Devils  Lake; 
next  it  flows  south  about  100  miles,  to  where  it  enters  the  area  of  Lake 
Agassiz;  and  thence  its  course  is  eastward  and  northward,  uniting  with  the 
Red  River  10  miles  north  of  Fargo  and  Moorhead.  Where  it  is  crossed 
by  the  Jamestown  and  Northern  Railroad,  south  of  the  west  end  of  Devils 
Lake,  its  elevation  is  1,410  feet  above  the  sea.  Thence  it  falls  to  1^064 
feet  at  Lisbon,  and  857  feet  at  its  mouth.  Along  its  eastward  and  south- 
ward course  it  flows  through  an  undulating  or  rolling  and  occasionally  hilly 
region,  in  which  its  valley  is  eroded  100  to  200  feet  deep.  Within  the  area 
of  Lake  Agassiz  it  has  cut  50  to  75  feet  into  its  delta,  and  beyond  occupies 


LANGS  VALLEY  AND  THE  PEMBINA  RIVER.  57 

a  channel  20  to  30  feet  below  the  flat  lacustrine  plain.  This  lower  portion 
of  the  river  is  mostly  from  50  to  75  feet  wide  and  1  to  3  feet  deep.  The 
Maple  River,  flowing  south  and  then  northeast,  parallel  with  the  Sheyenue, 
joins  this  river  about  8  miles  from  its  mouth.  The  large  valley  of  the 
upper  part  of  the  Sheyenne  River,  and  its  extensive  delta  deposited  in 
Lake  Agassiz,  are  attributable  to  a  stream  which  was  doubtless  much  larger 
than  the  present  Sheyenne,  formed  by  drainage  from  the  ice-sheet  when  it 
terminated  near  Devils  Lake.  At  that  time,  also,  a  glacial  lake  in  the  basin 
of  the  Souris  outflowed  southeastward  to  the  Sheyenne  and  James  rivers. 

Langs  Valley. — During  a  later  stage  in  the  recession  of  the  ice-sheet 
the  srlacial  Lake  Souris  was  extended  west  and  north  of  Turtle  Mountain 
and  finally  found  a  lower  outlet  in  southern  Manitoba.  Its  outflowing  river 
ran  southeasterly  from  the  elbow  of  the  Som-is,  18  miles  southwest  of  its 
mouth,  to  the  Pembina  River.  Pelican  Lake,  1 1  miles  long  from  northwest 
to  southeast  and  about  a  mile  wide,  occupies  a  part  of  the  channel  of  this 
stream;  and  a  distinct  water  course  of  similar  width,  called  Langs  Valley,^ 
eroded  110  to  150  feet  below  the  general  level,  extends  11  miles  between 
this  lake  and  the  Souris.  The  highest  portion  of  Langs  Valley  is  1,364 
feet  above  the  sea,  and  about  100  feet  above  the  Souris  at  its  elbow,  and  is 
inclosed  by  bluff's  110  feet  high.  It  is  a  channel  similar  to  that  of  Lakes 
Traverse  and  Big  Stone  and  Browns  Valley,  eroded  by  the  River  Warren, 
outflowing  from  Lake  Agassiz. 

Pembina  River. — The  Pembina  River  ^  flows  from  the  northern  part  of 
Turtle  Mountain  in  a  rather  crooked  easterly  course  through  southern 
Manitoba  and  the  edge  of  North  Dakota  about  130  miles,  measured  in  a 
direct  line,  to  its  mouth  at  Pembina  and  St.  Vincent.  From  its  junction 
with  the  outlet  of  Pelican  Lake  to  Walhalla,  at  the  base  of  the  First 
Pembina  Mountain,  its  valley  varies  from  175  to  450  feet  in  depth.  Rock 
Lake  and  Swan  Lake,  on  this  part  of  the  river,  each  several  miles  long  and 
from  a  half  mile  to  1  mile  wide,  are  due  to  deposits  brought  into  this  valley 
by  tributaries  after  it  ceased  to  be  the  avenue  of  drainage  from  the  Souris 

'Named  for  James  LauR,  Trbo  was  the  first  immigraut  here,  coming  in  1880. 

=This  name  is  stated  by  Keating  to  be  from  the  Ojil)wa.v  word  "aneiieniinan,  which  name  has 
been  shortened  and  corrupted  into  Pembina,"  meaning-  the  fruit  of  the  bush  cranberry  (  Viburnum 
opulua,  L.). — Narrative  of  Long's  Expedition.  Vol.  II,  p.  38. 


58  THE  GLACIAL  LAKE  AGASSIZ. 

basin.  In  crossing  the  Red  River  Valley  the  Pembina  runs  in  a  channel 
only  20  to  40  feet  deep.  Its  descent  from  the  northern  base  of  Tm-tle 
Mountain  to  Walhalla  is  about  700  feet,  and  thence  to  its  mouth  186  feet, 
its  junction  with  the  Red  River  being  748  feet  above  the  sea.  Long  or 
White  Mud  River,  Clear  Water  or  Cypress  River,  and  Tongue  River  are  its 
chief  tributaries,  all  from  the  south  side. 

Assiniboine  River. — The  largest  tributary  of  the  Red  River  is  the 
Assiniboine,  which  di-ains  a  basin  in  Assiniboia,  Manitoba,  and  North 
Dakota,  300  miles  wide  fx-om  south  to  north  and  400  miles  long  from  west 
to  east.  From  its  source  in  the  south  edge  of  Saskatchewan,  50  miles 
southwest  of  the  Porcupine  Hills,  the  Assiniboine  flows  south-southeasterly 
200  miles,  to  a  point  about  50  miles  below  the  mouth  of  the  Qu'Appelle 
and  40  miles  west  of  Brandon;  thence  it  flows  easterly  about  150  miles  to 
its  mouth.  Its  height  above  sea-level  at  the  mouth  of  the  Qu'Appelle 
is  1,264  feet;  at  the  bridge  of  the  Canadian  Pacific  Railway  near  Brandon, 
1,161  feet;  at  the  mouth  of  the  Souris,  about  1,075  feet;  at  Portage  la 
Prairie,  842  feet,  and  at  its  junction  with  the  Red  River  in  Wiiuiipeg,  724 
feet.  During  its  high  stages  of  water  the  Assiniboine  has  been  navigated 
by  steamboats  to  Fort  Pelly,  about  90  miles  above  the  mouth  of  the 
Qu'Appelle.     Along  this  portion  it  varies  from  10  to  25  rods  in  width. 

The  highest  floods  of  the  Assiniboine  at  Portage  la  Prairie  .and  along 
a  considerable  distance  eastward  rise  only  12  to  15  feet  above  its  lowest 
stage,  but  they  then  attain  a  height  only  a  few  feet  below  the  highest 
portions  of  the  adjoining  country,  much  of  which  is  submerged.  At  this 
extreme  height,  which  the  river  reached  and  maintained  from  the  3d  to  the 
15th  of  May,  1882,  the  only  time  of  such  high  water  since  1860  or  1861, 
it  overflowed  near  the  former  site  of  the  fort  of  the  Hudson's  Bay  Company, 
2  miles  southwest  of  Portage  la  Prairie,  and  a  portion  of  its  flood  passed 
north  in  shallow,  winding  watercourses  to  Lake  Manitoba,  making  a 
descent  of  about  40  feet  in  the  distance  of  15  miles  between  the  river  and 
the  lake.  Near  the  same  time  Lake  Manitoba  also  reached  its  highest 
stage,  about  8  feet  above  its  lowest  level,  rising  until  it  overflowed  south- 
ward across  the  east  part  of  township.  13,  range  6,  and  thence  eastward 
tln-ough  the  southern  row  of   sections  in  township   13,   range  5,  falling 


ASSmiBOINE,  QU'APPELLE  AND  SOUEIS  RIVERS.  59 

10  feet  in  15  miles  to  Long  Lake,  through  which  old  channel  of  the 
Assiniboine  its  waters  were  discharged  into  this  river  20  miles  east  of 
Portage  la  Prairie.^ 

The  excavation  of  the  Assiniboine  basin,  before  mentioned  in  con- 
nection with  the  description  of  Pembina,  Riding,  and  Dnck  mountains, 
depressing  much  of  its  area  hundreds  of  feet  below  the  great  plains 
farther  south,  was  effected  by  preglacial  rivers.  Over  the  irregular  surface 
thus  sculptured  a  thick  covering  of  glacial  di-ift  is  spread  somewhat  uni- 
formly, so  that  the  preglacial  contour  is  preserved  in  the  broader  outlines 
of  the  country;  but  the  smaller  inequalities  of  the  surface  and  the  present 
watercourses  have  been  formed  during  Glacial  and  Recent  time. 

While  Lake  Agassiz  held  nearly  its  highest  level,  the  Assiniboine 
brought  into  its  west  side  a  vast  delta,  of  gravel  and  sand,  which  extends 
from  Brandon  75  miles  east  to  Portage  la  Prairie,  and  from  Treheme, 
Glenboro,  and  Milford  40  miles  north  to  Gladstone  and  Neepawa.  Its  area 
is  fully  2,000  square  miles,  and  its  depth  probably  averages  50  feet,  with  a 
maximum  of  about  200  feet. 

Qu^Appelle  and  Souris  rivers. — The  Qu'Appelle  or  Calling-  River  and 
the  Souris  or  Mouse  River  are  the  largest  tributaries  of  the  Assiniboine. 
Each  of  these  streams  has  an  interesting  glacial  history,  which  is  recorded 
in  the  topographic  featm'es  of  their  valleys  and  areas  of  drainage.  The 
Qu'Appelle  Valley  was  eroded  by  the  outlet  of  a  glacial,  lake  in  the  basin 
of  the  South  Saskatchewan  River.  The  description,  map,  and  sections 
given  by  Hind^  show  that  this  valley  is  quite  uniformly  about  1  mile  wide, 
and  is  eroded  from  110  to  350  feet  below  the  general  level  of  the  region 
through  which  it  lies,  this  height  being  reached  by  steep  bluffs  on  each 
side.  Its  length  from  the  elbow  of  the  South  Saskatchewan  to  its  junction 
with  the  Assiniboine  is  about  270  miles,  the  general  course  being  a  little 
to  the  south  of  east.  Of  this  extent  the  west  end  of  the  valley  for  about 
12  miles  is  occupied  by  the  River  that  Turns,  and  the  remainder  by  the 
Qu'Appelle,  the  summit  or  height  of  land  in  this  channel  at  the  divide 

'Compare  H.  S.  Treherne's  description  of  this  vicinity,  "An  ancient  outlet  of  Lake  Manitoba," 
Nintli  Annual  Report  of  the  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  for  1880,  pp.  388-392. 

2  Report  ot  the  Assiniboine  and  Saskatchewan  Exploring  Expedition,  1859,  by  Heury  Youle  Hind. 


60  THE  GLACIAL  LAKE  AGASSIZ. 

between  these  rivers  being  85  feet  above  the  South  Saskatchewan,  440  feet 
above  the  mouth  of  the  Qu'Appelle,  and  1,700  feet  above  the  sea.  The 
inclosing  bhiflfs  are  composed  mainly  of  glacial  drift,  with  only  a  few 
exposures  of  the  underlying  Cretaceous  rocks.  The  alluvial  bottom  land 
of  the  Qu'Appelle  is  generally  from  a  half  mile  to  1  mile  wide,  and  through 
it  the  river  flows  in  a  winding  course,  here  and  there  passing- through.long 
lakes.  Like  the  similar  lakes  of  the  Pembina  and  Minnesota  rivers,  these 
owe  their  existence  to  the  recent  deposits  of  tributaries,  and  show  that  the 
bed  of  the  glacial  river  was  considerably  lower-  than  that  of  the  present 
stream.  The  outflow  of  the  Saskatchewan  glacial  lake,  fed  by  the  melting 
ice  fields  of  an  immense  area,  reaching  west  to  the  Rocky  Mountains,  took 
its  course  east  by  this  trough-like  channel  or  valley,  entering  the  Assini- 
boine  at  Fort  Ellice  and  reaching  the  border  of  Lake  Agassiz  at  Brandon. 

Long  or  Last  Moiintain  Lake,  about  50  miles  long  from  south  to  north 
and  1  to  2  miles  Avide,  lying  north  of  the  upper  j^art  of  the  QuAppelle 
and  tributary  to  it,  occupies  a  similar  glacial  watercourse.  The  elevation 
of  Long  Lake  is  1,598  feet,  being  about  100  feet  lower  than  the  divide  in 
the  channel  from  the  elbow  of  the  South  Saskatchewan  to  the  Qu'Appelle. 
It  seems  probable  that  when  the  ice-sheet  had  receded  so  far  north  as  to 
allow  the  Saskatchewan  Lake  to  extend  to  the  district,  northwest  and  north 
of  Long  Lake,  it  there  obtained  some  lower  point  of  discharge  and  out- 
flowed along  the  course  of  this  lake,  forsaking  its  former*  outlet.^  Owing 
to  the  changes  in  relative  elevation  which  have  taken  place  in  the  region  of 
Lake  Agassiz  since  that  time,  this  new  outlet,  or  the  earliest  and  highest 
one  of  several  successive  outlets,  across  the  watershed  between  the  Sas- 
katchewan basin  and  Long  Lake,  may  now  be  found  50  or  perhaps  even 
100  feet  higher  than  the  old  channel  to  the  head  of  the  Qu'Appelle — that 
is,  1,760  or  1,800  feet  above  the  sea,  the  possible  diff"erence  being  prob- 
ably as  much  as  a  foot  to  each  mile  of  the  distance  between  the  old  and 
new  outlets. 

Souris  River,  flowing  circuitously  southwestward  from  Assiniboia  into 
North  Dakota  and  thence  northeastwai'd  into  Manitoba,  became  tributary 
to  the.Assiniboine  after  the  waters  of  the  glacial  lake  in  its  own  basin,  at 

'Report  of  the  Assiniboine  and  Saskatchewan  Exploring  Expedition,  1859,  pp.  28,  35,  118. 


SASKATCHEWAN  EIVER.  61 

first  flowing  to  the  James  and  Sheyenne,  had  been  wholly  di*ained  away  by 
its  outlet  tlu'ough  Langs  Valley  and  the  Pembina  River.  The  length  of 
the  "Souris  is  nearly  400  miles,  but  it  is  only  5  to  10  rods  wide  along  its 
lower  portion.  In  North  Dakota  its  descent  is  approximately  from  1,650  to 
1,400  feet  above  the  sea,  and  thence  to  its  mouth  it  falls  about  325  feet. 

Little  Saskatchewan  or  Fairford  River. — An  area  that  extends  more  than 
200  miles  west  from  Lake  Wimiipeg  and  includes  an  equal  distance  in  lati- 
tude, from  the  most  northern  part  of  Lake  Winnipegosis  to  the  south  end 
of  Lake  Manitoba,  is  di-ained  by  the  Little  Saskatchewan  or  Fairford 
River.^  Several  small  streams  flow  into  the  south  end  of  Lake  Manitoba, 
and  the  Water  Hen  River,  the  outlet  of  Lake  Winnipegosis,  flows  into  its 
north  end.  Four  considerable  streams  are  tributary  to  Lake  Winnipegosis, 
namely;  Mossy  River,  the  outlet  of  Lake  Dauphin,  flowing  into  its  south 
end,  and  the  Swan,  Red  Deer,  and  Overflowing  rivers  at  its  northwest  end. 
Riding  and  Duck  mountains  form  the  southwestern  boundary  of  this  basin, 
but  the  Porcupine  Hills  are  entirely  inclosed  between  the  Swan  and  Red 
Deer  rivers,  and  the  latter  drains  much  of  the  plateau  bordered  by  the 
Pasquia  Hills. 

Saskatchewan  River. — The  lower  part  of  the  basin  of  the  Saskatchewan, 
next  to  its  mouth,  was  latest  occupied  by  the  ice-sheet;  but  that  area  was 
evidently  relinquished  by  it,  allowing  this  great  river  to  take  its  present 
course,  before  Lake  Agassiz  began  to  be  drained  northeastward.  From  the 
most  western  sources  of  the  Saskatchewan  in  the  Rocky  Mountains  to  its 
mouth  is  a  distance  of  more  than  700  miles,  and  the  maximum  width  of  its 
basin  is  about  350  miles.  Its  two  branches,  of  nearly  equal  size,  the  North 
and  South  Saskatchewan  rivers,  unite  230  miles  west  of  Lake  Winnipeg. 
The  elevation  of  the  South  Saskatchewan  at  Medicine  Hat,  where  it  is 
crossed  by  the  Canadian  Pacific  Railway,  is  2,137  feet;  at  its  elbow,  1,619 
feet,  approximately,  and  at  its  junction  with  the  North  Saskatchewan,  about 
1,200  feet.     Cedar  and  Cross  lakes,  through  which  the  Saskatchewan  flows 

'  The  portion  of  this  river  extending  10  miles,  with  a  descent  of  about  15  feet,  from  Lake 
Manitoba  to  Lake  St.  Martin,  is  commonly  called  the  Fairford  River,  and  the,  lower  portion,  extend- 
ing 31  miles  and  falling  85  feet  to  L.ike  Winnipeg,  is  known  as  the  Little  Saskatchewan. — J.  B. 
Tyrrell,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  IV,  for  1888-89, 
pp.  19-21A. 


62  THE  GLACIAL  LAKE  AGASSIZ. 

near  its  mouth,  are  apj^roximately  114  and  108  feet  above  Lake  Winni- 
peg, or  824  and  818  feet  above  the  sea.  Hind  informs  us  that  the  name 
Saskatchewan  means  "the  river  that  runs  swiftly;"  and  he  states  that  in 
the  Grand  Rapids,  between  Cross  Lake  and  its  mouth,  it  falls  43  feet  in  2  J 
miles.^  Its  average  descent  per  mile  from  Medicine  Hat  eastward  is  about 
2  feet.  The  Saskatchewan  and  both  its  north  and  south  branches  for 
several  hundi'ed  miles  above  their  jimction  vary  commonly  from  a  sixth 
to  a  third  of  a  mile  in  width,  and  during  favorable  stages  of  water  are 
navigated  by  steamboats  from  Cedar  Lake  to  Edmonton,  on  the  North 
Saskatchewan,  about  2,000  feet  above  the  sea,  and  beyond  the  confluence 
of  the  Bow  and  Belly  rivers,  which  form  the  South  Saskatchewan,  50  miles 
west  of  Medicine  Hat,  at  an  elevation  exceeding  2,200  feet.  The  chief 
hindrances  to  their  navigation  in  low  stages  are  shifting  sand  bars,  over 
which  they  expand  in  some  places  to  widths  of  a  half  mile  to  1  mile,  being 
very  shallow  and  divided  by  low  sandy  islands.  The  adjoining  country 
rises  within  a  few  miles  from  these  rivers,  or  at  the  farthest  10  or  20  miles, 
to  an  elevation  300  to  600  feet  or  more  above  them,  excepting  along  the 
last  hundred  miles  of  the  Saskatchewan,  where  it  flows  through  a  broad 
lowland  region.  There  the  highest  parts  of  the  country  are  only  50  to  100 
feet  above  the  river,  and  its  shores  are  generally  low  and  in  many  portions 
swampy. 

The  smaller  tributaries  of  Lake  Winnipeg. — Besides  the  great  affluents 
of  Lake  Winnipeg,  namely,  the  Winnipeg,  Red,  Little  Saskatchewan,  and 
Saskatchewan  rivers,  about  a  dozen  sti-eams,  varying  in  length  from  10 
to  40  miles,  enter  its  west  side,  and  twenty  or  more  of  similar  or  somewhat 
greater  length  enter  its  east  side.  Of  the  latter  the  largest  are  Berens  and 
Poplar  rivers,  each  about  100  miles  long.  The  recession  of  the  ice-sheet 
from  southwest  to  northeast  uncovered  the  entire  region  west  of  Lake 
Winnipeg,  and  probably  the  whole  of  the  country  traversed  by  these 
streams  on  the  east,  before  its  melting  finally  permitted  the  waters  of  the 
Glacial  Lake  Agassiz  to  be  di'ained  to  the  level  of  this  lake. 

Nelson  River. — The  outlet  of  Lake  Winnipeg,  as  before  noted,  is  bor- 
dered  by  no  areas  of  highland  along  its  course  of  about  400  miles  to 

'  Report  of  the  Assiniboine  and  Saskatchewan  Exploring  Expedition,  1859. 


TRIBUTAEY  AEEA  IN  THE  MACKENZIE  BASIN.  63 

Hudson  Bay.  The  upper  half  of  the  Nelson  flows  in  a  general  direction 
only  a  few  degrees  east  of  north,  passing  through  Great  and  Little  Play- 
green,  Pipestone,  Cross,  and  Sipi-wesk  lakes,  to  Split  Lake;  thence  it  turns 
to  the  east  for  about  100  miles,  passing  through  Gull  Lake,  and  finally 
takes  a  northeastward  course  along  its  lower  100  miles.  According  to  Dr. 
Bell's  observation,  Sipi-wesk  Lake  is  approximately  570  feet  above  the  sea, 
or  140  feet  below  Lake  Winnipeg;  Split  and  Gull  lakes  are  respectively 
about  440  and  420  feet  above  the  sea;  and  the  descent  in  the  next  48  miles, 
to  the  foot  of  Broad  Rapid,  is  nearly  300  feet.  The  Nelson  is  navigable 
from  the  sea  about  90  miles  to  the  First  Limestone  Rapid,  where  the  eleva- 
tion is  probably  aboiit  50  feet  above  the  sea-level. 

About  four-fifths  of  the  region  drained  by  the  Nelson,  including  the 
basins  of  the  Red  River  of  the  North,  the  Little  Saskatchewan,  and  the 
Saskatchewan,  and  the  greater  part  or  possibly  all  of  the  basin  of  the 
Rainy  and  Winnipeg  river  system,  were  uncovered  from  the  ice-sheet  and 
were  tributary  to  Lake  Agassiz  as  early  as  the  middle  portion  of  the  time 
while  it  had  its  southward  outlet.  The  waters  of  a  large  part  of  British 
America  were  thus  carried  along  the  com-se  of  the  Minnesota  and  the 
Mississippi  to  the  Gulf  of  Mexico.  The  basin  of  Lake  Agassiz  then 
included  approximately  350,000  square  miles,  of  which  nearly  a  third  was 
covered  by  the  lake  itself. 

EXTENSIOK  OF  THE  BASIN"  OF  LAKE  AGASSIZ  BY  GLACIAL  LAKES 
OUTFLOWING  TO  IT  FROM  THE  REGION  OF  THE  PEACE  ANT) 
ATHABASCA  RIVERS. 

Furthermore,  within  the  time  after  the  ice-sheet  had  retreated  beyond 
the  valley  of  the  lower  Saskatchewan,  and  before  its  melting  ujjon  Hudson 
Bay  and  the  adjoining  country  permitted  Lake  Agassiz  to  gain  an  outlet  to 
the  northeast,  it  seems  certain  that  the  ice  must  have  been  melted  upon 
a  large  region  north  of  the  Saskatchewan  basin,  where  drainage  now 
passes  east  by  the  Churchill  and  north  by  the  Mackenzie,  but  was  then 
pent  up  in  lakes  by  the  ice  barrier  and  caused  to  flow  to  the  south.  Lake 
Agassiz  thus  received  the  waters  of  the  upper  Churchill,  and  of  the  basins 
of  the  Athabasca  and  Peace  rivers,  the  great  head  streams  of  the  Mackenzie; 


64  THE  GLACIAL  LAKE  AGASSIZ. 

and  the  Churchill,  and  probably  also  the  upper  Mackenzie  basin,  continued 
to  be  tributary  to  this  lake  tlu'ough  all  its  lower  stages  of  outflow  to  Hudson 
Bay.  With  this  addition,  the  area  of  the  glacial  lake  basin  was  not  less 
than  500,000  square  miles. 

Extensive  areas  bordering  the  Peace  River  are  described  by  Dr.  G.  M. 
Dawson  as  "covered  supei-ficially  by  fine,  silty  deposits,  resembhng  those 
of  the  Red  River  Valley,  and  doubtless  indicating  a  former  great  lake  or 
extension  of  the  sea  in  the  time  immediately  succeeding  the  Glacial  period." 
The  exploration  of  ancient  shore-lines  is  very  difficult  in  that  generally 
forest-covered  region,  and  it  must  be  many  years  before  the  boundaries  and 
outlets  of  former  bodies  of  water  in  the  basins  of  the  Peace  and  Athabasca 
rivers  can  be  mapped;  but  it  may  be  predicted  with  reasonable  confidence 
that  these  basins,  now  drained  to  the  Mackenzie  and  the  Ai-ctic  Ocean,  will 
some  time  be  found  to  have  contained  glacial  lakes  outflowing  southeast- 
ward to  Lake  Agassiz.  Probably  the  earliest  outlet  from  the  glacial  lake 
of  the  Peace  River  was  across  the  watersheds  to  Lesser  Slave  Lake  and 
to  the  North  Saskatchewan  at  its  eastward  bend,  about  50  miles  below 
Edmonton;  and  the  latest  outflow  from  the  Athabasca  glacial  lake  appears 
to  have  formed  a  channel  across  the  Mackenzie  and  Churchill  divide  near 
the  famous  Methy  Portage. 

'  Descriptive    Sketch  of  the   Physical  Geography   and  Geology  of   the  Dominion  of  Canada, 
1884,  p.  32. 


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CHAPTER   III. 

GEOLOGIC  FORMATIONS  UNDERLYING  THE  DRIFT. 

Archean,  Lower  and  Upper  Silurian,  Devonian,  and  Cretaceous  forma- 
tions succeed  each  other  from  east  to  west  as  the  bed-rocks  of  the  area  of 
Lake  Agassiz  (PL  XIV).  'I'hey  will  be  briefly  described  here  in  this  order, 
which  is  that  of  their  age  and  supei'position,  begimiing  with  the  oldest  and 
lowest.  Throughout  large  portions  of  this  region,  including  the  whole 
district  drained  by  the  Red  River  in  Minnesota,  the  underlying  rocks  are 
covered  by  the  glacial  drift,  and  afford  no  outcrops ;  but  their  character  and 
approximate  boundaries  on  these  tracts  are  inferred  with  much  probability 
from  the  nearest  outcrops,  from  topographic  features,  from,  the  bowlders 
and  other  material  of  the  drift,  and  from  sections  shown  by  deep  wells 
which  pass  through  the  drift  to  the  rocks  beneath. 

Intervening  in  stratigraphic  order  between  the  Archean  and  Silurian 
systems  are  large  areas  of  the  Algonkian  and  Cambrian  systems,  as  mapped 
on  PI.  XIV  for  the  country  about  the  west  part  of  Lake  Superior;  but  the 
Algonkian  and  Cambrian  rocks  probably  have  no  outcrops  on  the  Lake 
Agassiz  area. 

ARCHEAN    FORMATIONS. 

On  the  east  side  of  the  south  part  of  Lake  Agassiz  a  belt  of  Ai'chean 
rocks  extends  from  the  Minnesota  River  northeast  and  north,  partly  covered 
west  of  Lake  Superior  by  the  Algonkian  formations,  through  central  and 
northern  Minnesota,  where  it  widens  into  the  m  ain  area  of  these  rocks  in 
North  America.  This  great  Archean  area  stretches  from  Labrador  and 
the  lower  St.  Lawrence  southwest  to  Georgian  Bay  of  Lake  Hm-on,  west 
to  Lakes  Superior  and  Winnipeg,  and  thence  northwest  and  north  to  the 
Arctic  Sea.  Its  western  border  was  covered  by  Lake  Agassiz  from  the 
Lake  of  the  Woods  to  the  north  end  of  Lake  Winnipeg. 

65 

MON  XXV 5 


66  THE  GLACIAL  LAKE  AGASSIZ. 

THK    ARCHEAN    AREA    IN    MINNESOTA. 

The  most  soutliwesteru  outcrops  of  Arclieau  formations  in  Minnesota 
are  10  to  20  miles  southwest  of  the  Minnesota  River  in  Redwood  and 
Yellow  Medicine  counties,  where  small  isolated  exposures  of  granite,  gneiss, 
and  schists  occur.  The  deeply  eroded  valley  of  the  Minnesota  River, 
channeled  by  the  River  Warren,  outflowing  from  Lake  Agassiz,  cuts  thi'ough 
the  drift  sheet  to  the  bed-rocks,  which  from  Big  Stone  Lake  to  Little  Rock 
Creek,  4  miles  below  Fort  Ridgely,  are  Archean  gneisses,  A^arying  from  a 
granitoid  to  a  schistose  structure.  In  the  next  13  miles  no  rocks  older 
than  the  Cretaceous  are  found.  Then  comes  the  last  Archean  outcrop,  a 
coarse  granite,  opposite  to  the  southeast  part  of  New  Ulm,  succeeded  east- 
ward by  Algonkian  conglomerate  and  quartzite.  Observations  of  the  strike 
and  dip  of  the  Archean  rocks  exposed  in  this  valley  show  that  the  axial 
lines  of  their  folds  run  mainly  from  southwest  to  northeast. 

Central  Minnesota  has  frequent  Archean  outcrops  in  Stearns,  Benton, 
and  Morrison  counties,  including  the  valuable  quarries  of  St.  Cloud,  Sauk 
Rapids,  and  Watab.  The  greater  part  of  this  area  is  hornblendic  granite, 
and  exhibits  no  laminated  or  gneissic  structure.  It  has  considerable  variety 
of  texture  as  to  its  coarseness  of  grain  and  readiness  to  be  quarried  and 
wrought  into  any  required  form.  Mostly  its  color  is  light-gray,  but  upon 
some  extensive  tracts  it  has  a  red  tint  similar  to  that  of  the  celebrated 
granite  of  Aberdeen,  in  Scotland.  In  other  portions  of  this  district,  mica- 
ceous granite,  gneiss,  and  mica-schist  are  the  common  rocks,  sometimes 
associated  with  hornblendic  granite.  Their  strike  is  usually  to  the  north- 
east or  east-northeast.  At  Little  Falls  and  Pike  Rapids,  on  the  Mississippi, 
and  for  several  miles  to  the  south,  Avest,  and  north,  as  also  in  northern  Todd 
County,  and  along  the  falls  of  the  St.  Louis  above  Fond  du  Lac,  and  thence 
northeastward,  is  a  group  of  rocks  quite  different  from  the  foregoing,  its 
range  of  variation  being  from  highly  cleavable  clay-slate,  and  from  mica- 
schist,  inclosing  many  crystals  of  staurolite  and  sometimes  garnet  and  iron 
pyrites,  to  very  compact,  tough,  and  massive  diorite.  Comparing  these 
rocks  Avith  the  divisions  of  the  Archean  recognized  in  Canada  and  elsewhere, 
the  granites  and  gneisses  appear  to  represent  the  Laurentian,  Avhile  the 
slate,  staurolitic  schist,  and  diorite  are  probably  Keewatin. 


THE  AECHEAN  AREA.  67 

VICINITY    OF    THE    LAKE    OF    THE    WOODS,    KAINY    LAKE,    A>D    NORTHWARD. 

Belts  of  granite,  g-neiss,  schists,  quartzites,  and  slates,  belonging-  to  the 
Ai'chean  group,  alternate  with  one  another,  trending  to  the  east  or  northeast, 
along  the  international  boundary  from  the  Lake  of  the  Woods  to  Lake 
Superior.  In  the  region  about  the  Lake  of  the  Woods  they  have  been 
described  very  fully  by  Dr.  A.  C.  Lawson.^  The  group  is  there  di^'isible 
into  two  systems,  the  older  being-  the  Laurentian  granitoid  gneisses,  and 
the  newer  a  series  of  schists,  quartzites,  and  slates,  named  Ijy  Lawson  the 
Keewatin  series.  In  later  publications  by  Dr.  Lawson  on  the  geology  of 
the  Rainy  Lake  region,^  his  descriptions  show  that  subsequent  to  the 
deposition  of  a  measured  thickness  of  2  miles  of  mica-schists  and  granulitic 
gneisses,  named  by  him  the  Coutchiching  series,  well  developed  about 
Rainy  Lake,  and  of  the  Keewatin  series  north  of  Rainy  Lake  and  about 
the  Lake  of  the  Woods,  the  whole  Archean  group  in  this  district,  comprising 
a  vast  thickness  of  sedimentary  and  volcanic  rocks,  and  perhaps  below 
these  including  a  part  of  the  first-formed  crust  of  the  globe,  was  subjected 
to  metamorphism  from  the  heat  of  the  earth's  interior,  whereby  the  lowest 
beds  observed,  to  which  the  name  Laurentian  is  restricted  by  Lawson,  were 
so  fused  that  portions  of  them  were  extravasated  through  the  overlying 
Coutchiching  and  Keewatin  beds.  Sucli  division  remains  yet  to  be  worked 
out  for  nearly  all  qf  the  Arcliean  area  east  and  north  of  Lake  Winnipeg, 
but  is  reported  and  mapped  by  Dr.  Robert  Bell  in  the  country  bordering 
the  Hayes  and  Nelson  rivers. 

BOUNDARY  OF  THE  ARCHEAN  TOWARD  THE  WEST. 

Though  the  western  boundary  of  the  Archean  area  in  Minnesota  is 
mainly  covered  by  drift  and  by  remnants  of  Cretaceous  beds  beneath  the 
drift,  it  is  somewhat  definitely  known  for  a  distance  of  160  miles  from  New 
Ulm  west,  northwest,  and  north,  to  the  south  end  of  Lake  Agassiz.  Cross- 
ing the  Minnesota  River  from  the  noi'th  at  New  Ulm,  it  runs  westerly  about 
40  miles,  and  thence  northwesterly  across  Redwood,  Yellow  Medicine,  and 

'Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  I,  1885,  Part  CC. 
2 Am.  Jour.  Soi.  (3),  Vol.  XXXIII,  ]>p.  473-180,  June,  1887.     Geol.  and  Nat.  Hist.  Survey  of  Can- 
ada, Annual  Report,  Vol.  Ill,  for  1887-88,  Part  F. 


68    .  THE  GLACIAL  LAKE  AGASSIZ. 

Lac  qui  Parle  counties  almost  parallel  with  the  Minnesota  River,  but  grad- 
ually approaching  neai'er  to  it  and  cm-ving  north  to  the  mouth  of  Big  Stone 
Lake.  Thence,  beneath  a  veneer  of  the  Cretaceous  shales  and  overlying 
glacial  di-ift,  it  passes  north-northeasterly  to  the  west  part  of  Grant  County, 
where  a  well  at  Herman,  189  feet  deep,  encountered  Archean  rocks  at  a 
depth  of  132  feet.  This  well  first  went  through  124  feet  of  till,  and  then 
thi-ough  7  or  8  feet  of  fine-grained,  buff  maguesian  limestone.  The  remain- 
ing 57  feet  were  quartzose  granite,  -with  red  feldspar,  white  micaceous 
quailzite,  and  mica-schist  of  several  varieties.-^ 

Farther  to  the  north,  through  Minnesota,  this  boundary  is  more  con- 
jectural because  of  the  almost  entire  absence  of  exposures  of  the  bed-rocks. 
Entering  the  area  of  Lake  Agassiz  east  of  Red  Lake,  it  turns  to  the  north- 
west and  traverses  a  region  wholly  drift-covered,  passing  not  far  west  of 
the  Lake  of  the  Woods. 

North  of  the  international  boundary  this  limit  of  the  Ai'chean  area 
extends  a  little  west  of  north  to  the  south  end  of  Lake  Winnipeg,  a  few 
miles  east  of  the  mouth  of  the  Red  River,  and  thence,  continuing  in  the 
same  direction,  it  follows  the  east  shore  of  Lake  Winnipeg  along  its  whole 
extent  to  the  mouth  of  the  lake.  The  farther  course  of  this  line,  accord- 
ing to  the  observations  of  Sir  John  Richardson  and  later  explorations  by 
Dr.  Bell  and  others,  of  the  Geological  Survey  of  Canada,  is  west-northwest 
from  the  mouth  of  Lake  Winnipeg  and  the  west  side  of  Great  Playgreen 
Lake  to  the  south  side  of  Beaver  Lake  and  Lac  la  Rouge,  a  distance  of 
275  miles,  and  thence  it  curves  gradually  to  the  northwest,  crossuag  the 
Chm'chill  at  the  north  extremity  of  Isle  k  la  Crosse  Lake. 

JLOWER    SIIiUKIAN    FOKISIATIONS. 

In  journeying  from  south  to  north  along  the  Red  River  Valley,  the 
first  rock  exposures  found  are  Lower  Sikman  strata,  chiefly  magnesian 
limestones,  which  outcrop  in  Manitoba  at  numerous  localities  12  to  20 
miles  north-northeast  of  Winnipeg,  and  similar  outcrops,  probably  in  part 
of  Upper  Silurian  age,  which  rise  above  the  general  surface  of  drift  5  to  20 
miles  northwesterly  from  Winnipeg  and  at  about  the  same  distances  west  of 

'Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Sixth  Annual  Report,  for  1877,  p.  29;  Final  Report, 
Vol.  11,  1888,  p.  503. 


THE  LOWER  SILUEIAN  AREA.  69 

the  river.  Farther  north  Lower  Silurian  rocks  are  exposed  on  many  of  the 
islands  of  Lake  Winnipeg  and  along  its  western  shore,  but  no  exposures  of 
the  underlying  Cambrian  beds,  which  are  peneti-ated  by  the  artesian  well 
at  Grafton,  N.  Dak.,  have  been  found  in  this  region.  Against  the  western 
border  of  the  folded  and  eroded  Archean  rocks  the  Lower  Silurian  forma- 
tions repose  with  nearly  horizontal  stratification.  Their  general  dip,  vary- 
ing from  a  few  feet  to  10  feet  or  more  per  mile,  is  westward,  at  right  angles 
with  the  axis  of  Lake  Winnipeg  and  the  line  of  junction  of  the  Archean 
and  Paleozoic  rocks. 

Descriptions  of  the  outcrops  of  Silimau  and  Devonian  strata  in  Mani- 
toba will  prepare  us  to  consider  afterwards  the  sections  of  artesian  wells 
farther  south,  which  give  evidence  that  Silurian  formations  immediately 
underlie  the  drift  upon  a  large 'portion  of  the  Red  River  Valley,  on  both 
sides  of  the  international  boundary  and  of  the  river,  where  no  rock  expo- 
sures exist. 

Outcrops  on  Lake  Winnipeg. — Near  Grindstone  Point,  on  the  west  side 
of  Lake  Winnipeg,  60  miles  north  from  the  south  end  of  the  lake.  Hind 
observed  a  section  of  18  feet  of  level  limestone  overlying  20  feet  of  sand- 
stone, and  refers  it,  upon  the  evidence  of  its  fossils,  to  the  Chazy  epoch.^ 
Beds  of  limestone,  shale,  and  sandstone  are  also  described  by  Hind  on  Deer 
Island,  about  8  miles  south  of  Grindstone  Point,  being  apjDarently  the  same 
strata  as  at  that  locality;  and  Panton  reports  an  extensive  outcrop  of  lime- 
stone on  the  west  part  of  Big  Island,  a  few  miles  east  from  Deer  Island, 
and  other  exposures  of  the  same  on  Punk  Island,  3  or  4  miles  to  the  north. 
Black  Bear  Island,  a  few  miles  northwest  from  the  Narrows  at  Dog  Head, 
and  Berens  or  Swampy  Island,  about  40  miles  farther  north,  also  contain 
low  outcrops  of  limestone,  which  Panton,  who  refers  them  to  the  same 
formation  with  the  foregoing,  found  sparingly  fossiliferous  on  the  former 
but  richly  so  on  the  latter  of  these  islands.^ 

'Eeport  of  the  Assiuiboine  and  Saskatchewan  Exploring  Expedition,  1859,  p.  8G.  These  beds 
seem  equivalent  with  the  well-defined  limestone  stratum,  about  30  feet  thick,  richly  fossiliferous, 
which  has  been  commonly  called  the  Trenton  limestoue  in  southeastern  Minnesota,  but  which  is 
recently  referred  by  Mr.  E.  0.  Ulrich  to  the  Chazy  or  perhaps  the  Black  Eiver  formation  (Geol.  and 
Nat.  Hist.  Survey  of  Minn.,  Fourteenth  Annual  Report,  for  1885,  p.  57). 

2  "Notes  on  the  geology  of  some  islands  in  Lake  Winnipeg,'"  by  J.  Hoyes  Panton.  Transactions 
of  the  Historical  and  Scientific  Society  of  Manitoba,  January  28,  1886. 


70  THE  GLACIAL  LAKE  AGASSIZ. 

The  basal  sandstone  of  these  sections  is  the  lowest  formation  exposed 
in  this  basin  above  the  Archean  rocks.  It  is  regarded  by  Mr.  J.  B.  Tyrrell, 
of  the  Canadian  Geological  Survey,  who  has  recently  examined  the  lake 
region  of  Manitoba,  as  of  the  same  age  with  the  Chazy  limestone  of  New 
York  and  the  St.  Peter  sandstone  of  the  Upper  Mississippi.  He  reports 
its  thickness  to  be  about  100  feet,  consisting  of  "white  quartzose  sandstone, 
with  generally  well-rounded  grains,  running  down,  at  the  bottom,  into  a 
quartzose  conglomerate."  ^ 

The  overlying  limestone,  called  the  Trenton  formation  by  Whiteaves 
and  Tyrrell,  appears  to  represent  both  the  Trenton  and  Galena  formations 
of  the  Mississippi  Valley.  It  is  described  by  Tyrrell  as  "consisting  at  the 
bottom  of  a  mottled  buif  and  gray  dolomitic  limestone,  found  at  Big  and 
Swampy  islands,  etc.,  and  probably  also  at  East  Selkirk,  above  which  are 
other  hoiizontal  and  evenly  bedded  limestones  and  dolomites,  amounting  in 
all  to  a  few  hundred  feet,  and  all  more  or  less  rich  in  fossils."^ 

Next  in  ascending  order,  these  authors  identify  the  Hudson  River 
formation,  the  highest  member  of  the  Lower  Silurian  system,  "represented 
by  less  than  100  feet  of  fossiliferous  shales  and  dolomites,"  at  Stony  Moun- 
tain, at  Clarks  Point  and  Harbor,  on  the  west  shore  of  Lake  Winnipeg,  and, 
10  miles  south  of  the  last-named  locality,  on  the  Little  Saskatchewan  River 
from  1  to  3  miles  above  its  mouth. 

East  Selkirk. — Dolomitic  limestone,  having  a  light-buff  or  cream  color, 
delicately  and  very  in-egularly  streaked  and  mottled  with  light  yellowish 
brown,  is  quarried  in  three  localities  near  East  Selkirk,  on  the  Red  River, 
about  20  miles  north-northeast  of  Winnipeg.  It  has  been  much  disturbed 
by  glacial  agencies,  and  most  of  the  quarrying  is  of  large  detached  blocks, 
which  have  been  removed  slightly  froin  their  original  ^josition  and  are 
embedded  in  the  drift.  In  one  of  the  excavations  a  thickness  of  10  or  12 
feet  of  the  stone  is  seen  in  place,  having  a  horizontal  stratification,  at  an 
elevation  approximately  730  to  740  feet  above  the  sea.     It  contains  abun- 

'  "Three  deep  wells  in  Manitoba."  Trans.  Roy.  Soc.  Canada,  Vol.  IX,  sec.  4,  1891,  p.  91.  Sum- 
mary Report  of  the  Geological  Survey  of  Canada  for  1891,  p.  18. 

-J.  B.  Tyrrell,  as  before  cited.  J.  F.  Whiteaves,  "The  Orthoceratidie  of  the  Trenton  limestone 
of  the  Winnipeg  Basin."    Trans.  Roy.  Soc.  Canada,  Vol.  IX,  sec.  4, 1891,  pp.  77-90. 


LOWEE  FORT  GARRY  AND  STONY  MOUNTAIN.  71 

dant  fossils,  from  which  Mr.  Whiteaves  decides  its  age  to  be  that  of  the 
"Galena  limestones  of  the  west,  equivalent  to  the  Utica  shales."^ 

Lower  Fort  Garry. — About  5  miles  southwest  from  these  quarries, 
similar  limestone  is  exposed  on  the  west  bank  of  the  Red  River,  at  Lower 
Fort  Garry,  commonly  called  the  "Stone  fort,"  and  along  a  distance  of  a 
half  mile  to  the  south.  It  rises  15  to  20  feet  above  the  river,  its  top  being 
about  730  feet  above  the  sea.  This  also  contains  many  fossils,  among 
which  are  several  species,  according  to  Panton,  that  are  not  found  at  East 
Selkirk,  but  occur  at  Stony  Mountain.  The  same  formation  has  another 
low  exposure  on  the  Red  River,  about  4  miles  farther  south.  From  the 
former  of  these  outcrops,  close  to  the  fort,  Owen  collected  fossils  which  he 
pronounced  identical  with  those  of  the  Upper  Magnesian  or  Galena  lime- 
stone of  Wisconsin  and  lowa.^ 

Stony  Mountain. — Twelve  miles  north-northwest  of  Winnipeg,  and  an 
equal  distance  west  of  Lower  Fort  Garry,  is  the  hill  called  Stony  Moun- 
tain, well  described  by  Panton  as  "like  an  island  of  limestone  raised  above 
the  surface  of  the  surrounding  prairie  some  60  feet.  *  *  *  It  is  several 
miles  in  circumference  and  resembles  in  outline  the  shape  of  a  horseshoe. 
The  west  and  north  sides  are  quite  steep,  and  along  the  escarpments  the 
exposed  edges  of  the  strata  are  easily  observed,  while  the  east  gradually 
slopes  to  the  prairie  level."  The  highest  beds  at  the  quarries  on  the  west 
side  of  Stony  Mountain  are  hard,  brownish-gray,  dolomitic  limestone,  about 
40  feet  thick  (from  825  to  785  feet,  approximately,  above  the  sea),  showing 
only  few  and  obscure  fossils,  chiefly  corals;  next  is  a  reddish-gray  lime- 
stone, with  clayey  partings,  about  10  feet,  very  fossiliferous,  containing 
many  brachiopod  shells ;  and  beneath  these  beds  a  well  at  the  penitentiary 
penetrated  60  feet  of  partially  cherty  shales,  varying  in  color  from  yellow 
to  red. 

Little  Stony  Mountain. — Eight  miles  south  of  Stony  Mountain  and  5 
miles  west-northwest  of  Winnipeg,  an  outcrop  of  limestone,  known  as 
Little  Stony  Mountain,  has  been  quarried  for  lime-burning.  The  surface 
here  rises  30  or  40  feet  in  a  half  mile,  from  east  to  west,  to  the  limekiln  and 

'  Descriptive  Sketch  of  the  Physical  Geography  anil  Geology  of  the  Domiuion  of  Canada,  by  A. 
R.  C.  Selwyn  and  G.  M.  Dawson,  1884,  p.  37. 

2  Report  of  a  Geological  Survey  of  Wisconsin,  Iowa,  and  Minnesota,  1852,  p.  181. 


72  THE  GLACIAL  LAKE  AGASSIZ. 

quan-ies,  wliicli  are  about  800  feet  above  tlie  sea,  and  thence  it  holds 
nearly  this  height  westward.  The  limestone,  shown  to  a  depth  of  about 
10  feet,  is  apparently  the  same  as  that  forming  the  upper  part  of  Stonj- 
Mountain.  It  lies  in  beds  mostly  1  to  2  feet  thick,  horizontal,  or  in  part 
dipping  1  to  2  degrees  to  the  south-southwest. 

Stonewall. — At  Stonewall,  5  miles  northwest  of  Stony  Mountain,  a  hard 
and  cherty  limestone  has  been  extensively  quaiiied,  exposing  a  vertical 
section  of  1 7  feet.  The  upper  layers  of  this  rock  to  a  thickness  of  7  or  8 
feet  are  white  and  fossiliferous,  but  it  gi-adually  changes  below  to  a  red 
sti'atum  which  has  no  fossils. 

From  his  study  of  the  fossils  collected  in  these  outcrops  on  the  Red 
River  and  westward,  Mr.  Panton  concludes  that  their  ascending  strati- 
gi-aphic  order  is  the  same  as  their  geogi-aphic  order  from  east  to  west,  and 
wi'ites  of  the  series  as  follows: 

The  Selkirk  rock  has  a  most  comprehensive  group  of  fossils,  there  being  repre- 
sentatives of  several  beds,  but  taking  them  as  a  whole  the  Trenton  fossils  are  best 
represented.  The  rocks  at  Lower  Fort  Garry  seem  to  indicate  a  transition  bed 
between  those  of  East  Selkirk  and  the  lower  layer  at  Stony  Mountain.  They  contain 
forms  common  to  both.  The  fossils  of  the  lower  layers  at  Stony  Mountain  bear  a 
marked  resemblance  to  those  found  in  the  Hudson  River  group  elsewhere,  while 
the  higher  dolomitic  beds  and  those  of  Stonewall  probably  border  on  the  Niagara 
formation.' 

UPPER    SILURIAN   AND    DEVONIAN   FORMATIONS. 

West  of  these  Lower  Silurian  strata,  rocks  of  Devonian  age,  mostly 
pale-gray  or  buff  magnesian  limestones,  occur  on  Lakes  Manitoba  and 
Winnipegosis,  as  reported  in  1884  by  Dr.  G.  M.  Dawson;  "and  it  is 
probable,"  he  wrote,  "that  the  intervening  formations  will  be  found  to  be 
extensively  developed  in  the  Lake  Wiimipeg  region  as  it  is  more  fully 
examined."^ 

Subsequent  exploration  of  this  region  by  Mr.  J.  B.  Tyn-ell  has  resulted 
in  the  discovery  of  Upper  Silm-ian  strata,  containing  fossils  characteristic 

'"Gleanings  from  outcrops  of  Silurian  strata  in  the  Eed  River  Valley."     Transactions  of  the 
Historical  and  Scientific  Society  of  Manitoba,  November  27,  1884. 

•Descriptive  Sketch  of  the  Physical  Geography  and  Geology  of  Canada,  p.  37. 


UPPER  SILURIAN  AND  DEVONIAN  AREAS,  73 

of  the  Niagara  formation,  ou  the  lower  part  of  the  Saskatchewan  River 
and  on  the  east  side  of  Lakes  Manitoba  and  Winnipegosis.  In  the  gorge 
of  the  Grand  Rapids  of  the  Saskatchewan  this  formation,  according  to 
Tyrrell,  "consists  in  its  lower  portion  of  about  60  feet  of  buff,  yellow,  and 
white  limestone,  brecciated  at  the  bottom  and  ripple-marked  toward  the 
top.  Some  bands  are  highly  fossiliferous.  *  *  *  The  upper  portion 
of  the  formation  consists  of  a  considerable  thickness  of  a  compact  or  jiorous 
dolomite,  often  containing  many  impressions  of  salt  crystals.  *  *  * 
The  highest  beds  at  Stonewall  may  belong  to  this  teiTane."^ 

Overlying  the  typical  Niagara  dolomites,  Mr.  Tyrrell  finds,  near  the 
northeastern  angle  of  Lake  Manitoba,  "a  few  feet  of  thick-bedded  stroma- 
toporoid  magnesian  limestone  holding  Pycnostylus  Guelpliensis,"  which  he 
thinks  to  be  probably  referable  to  the  Guelph  formation,  next  above  the 
Niagara  in  the  Upper  Silurian  series. 

The  succeeding  strata  of  this  disti'ict,  in  ascending  order,  shown  to  be 
soft  shales  in  the  sections  of  wells  at  Rosenfeld  and  Morden,  have  not  been 
found  in  outcrops.  These  beds  doubtless  represent  higher  formations  of 
Upper  Silurian  age  and  the  base  of  the  Devonian  system,  which  latter 
seems  to  be  identified  by  fossils  of  the  Morden  section. 

Devonian  strata  are  reported  by  Tyrrell  on  the  western  shores  and 
islands  of  Lake  Manitoba  and  Lake  Winnipegosis,  being  especially  well 
exhibited  in  the  islands  of  Dawson  Bay  and  of  Swan  Lake,  which  lies  a 
few  miles  south  of  this  bay.  Above  an  exposure  of  a  few  feet  of  red 
shales,  the  Devonian  series  in  these  outcrops  comprises  200  feet  or  more  of 
fossiliferous  magnesian  limestone,  an  overlying  thickness  of  50  to  70  feet 
of  calcareous  shales,  whose  horizon  is  marked  by  many  brine  springs,  and 
higher  beds  of  richly  fossiliferous  limestone.^ 

All  the  Paleozoic  formations  in  the  lake  region  of  Manitoba,  from  the 
St.  Peter  sandstone  to  the  highest  Devonian  beds  exposed,  are  stated  by 
Mr.  Tyrrell  to  be  "practically  conformable  and  almost  undisturbed  through- 

'"Three  Deep  Wells  in  Manitoba."    Trans.  Eoy.  Soc.  Canada,  Vol.  IX,  sec.  4,  1891,  p.  91. 

*J.  B.  Tyrrell,  paper  before  cited;  also,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report, 
new  series,  Vol.  IV,  for  1888-89,  pp.  21,  22A.  J.  F.  Whiteaves,  "Descriptions  of  some  new  or  previ- 
ously unrecorded  species  of  fossils  from  the  Devonian  rocks  of  Manitoba,"  Trans.  Roy.  Soc.  Canada, 
Vol.  VIII,  sec.  4,  pp.  93-110,  witli  seven  plates. 


74  THE  GLACIAL  LAKE  AGASSIZ. 

out."  At  Point  Wilkiiis,  on  the  west  side  of  Dawson  Bay,  the  Dakota 
sandstone,  forming  the  base  of  the  Cretaceous  series  which  underlies  the 
drift  farther  west,  was  seen  lying  on  the  eroded  surface  of  the  horizontally 
stratified  Devonian  limestones. 

Along  the  Saskatchewan,  Silurian,  and  Devonian  strata,  mainly  lime- 
stones, reach  from  Lake  Winnipeg  to  Fort  h  la  Corne,  about  12  miles  below 
the  junction  of  the  south  and  north  branches  of  this  river.  Thence  to  the 
northwest  and  north,  a  belt  of  these  rocks,  in  large  part  almost  horizontally 
bedded,  skirts  the  west  side  of  the  Archean  area  to  the  Arctic  Sea. 

SECTIONS  OF  ARTESIAN  WELLS  IN  PALEOZOIC   STRATA. 

Four  deep  borings  for  artesian  water  reveal  the  order  and  thickness  of 
the  several  members  of  the  Paleozoic  group  forming  the  floor  of  the  Red 
River  Valley  .beneath  the  drift  in  the  vicinity  of  the  international  boundary. 
These  wells,  in  their  order  from  east  to  west,  are  situated  at  Humboldt  in 
Minnesota,  Grafton  in  North  Dakota,  and  Rosenfeld  and  Morden  in  Mani- 
toba. Notes  of  their  sections  are  presented  in  the  following  pages,  and 
their  stratigraphic  relationship  is  shown  in  PI.  XV. 

The  well  at  Morden  penetrates  only  to  the  base  of  the  Devonian  or 
top  of  the  Upper  Silurian.  The  Rosenfeld  well,  entering  the  bed-rocks  at 
a  horizon  near  that  where  the  Morden  well  left  off,  gives  apparently  a 
complete  section  of  the  Upper  and  Lower  Silurian  series,  passing  at  its 
bottom  through  the  Lower  Magnesian  formation,  which  is  the  base  of  the 
latter,  lying  next  below  the  St.  Peter  sandstone.  Another  section  of  the 
Lower  Silurian  formations,  from  the  Galena  and  Trenton  to  the  Lower 
Magnesian,  is  supplied  by  the  well  at  Humboldt;  and  the  Grafton  section, 
besides  duplicating  that  of  Humboldt,  passes  nearly  300  feet  beyond  in 
probably  Upper  Cambrian  strata,  referable  to  the  Jordan,  St.  Lawrence, 
and  Dresbach  formations  of  the  St.  Croix  series. 

WELL   AT    HUMBOLDT,    MINN. 

Humboldt  is  a  station  of  the  Great  Northern  Railway,  about  7  miles 
southeast  of  St.  Vincent,  at  the  farm  of  Mr.  D.  H.  Valentine,  on  which  this 
well  is  situated.     It  is  on  the  flat  plain  of  the.  Red  River  Valley,  6  miles 


U.S. GEOLOGICAL  SURVEY. 

_ 

MONOGRAPH  XXV. 

PL.  XV. 

MORDEN. 

24  miles  wo.st  ofRosenfcld. 

Surface, 978  iect  above  llif  sea. 

^ 

JV»(^07ldJfl»u( 

31  feel 

15 

'fiP 

16  feetTiU 

DRIFT 

31 

2-t  feet 

O  (irk  shale 

S£ 

Ft-Pienv. 

-900 

^ 

GRAFTON. 

900- 

^ 

IGO  reel 

3ii  miles  south-southwf st  ot'Humbohil 

^ 

Dark  ffray 
'mosCb'ca/m  m>us 

shales 
Xiobrara. 

ROSEN  FELD.             Surfac 

e.025  feet  above  the  sea  . 

^ 

30  miles  iiurtlmesl  ur  Huraboldl 

3 

3  feet     Sou 

HUMBOLDT. 

-800 

^ 

Surl'ace.Ty^  feet  above  tlie  sea 

z^ 

25  fetit.  Clay 

Surface 

,792  feel  above  the  sea. 

8O0  - 

S 

■' 

an 

-/  />*■  e  Soil 

25 

~ 

^■ 

"'/S,Va„a       ^ 

:=^^ 

38/  feet 

-.;;: 

^ 

ie 

^ 

sandy  clay 

2W 

S 

■CRETACEOUS 

1 

nifeet 
StnUified 

J-t3  f'ceL 

i 

'i^ 

124    feel 

-700           "/ 

^ 

tOS  feet 
Dark  gray 

— -^rAes. — 

FtBenton 

3S 

day.duinginq 
total  beOiw     [ 

0_R1_FT 

g. 

oT 

Darker  clay, 
changing' 
dow^nward 
intoTiU 

710  FcEZ  Level 

OF 

;7^- 

^-T 

2'JS     feet 

r7 

LAK£W/IVNIPEG\     1 
rao  feet                                \     1 

"^ 

lis 

(if 

IOfl£ra\el 

:i^. 

25U  feet 
Da/Aer  stratified 

DRIFT 

'''■-_ 

DRIFT 

320 

r^ 

131 

^^ 

nriHaitiuii 

cUly.  chanqifta 
to'TUU>e&w 

'  ~7 

-600         3ao 

1 

eoteet 

JO  reetson 
gruTdkaU 

5 

^ 

OftBov.lda^ 

62  feet 

Gray  shale 

L? 

no 

170 
180 

?7f 

'''^'!§LyUu.l,U. 
containinq 
salt  -watir. 

10  ft. Gravel 

600- 

390 

too 

■H2 

S 

izfheteray 
3hafysaTid  - 

4 

^ 

205 
225 

1 

15  feet 

Buff  limestone 
SftetRedsluUe 

&° 

ijj 

Stona 

233 

2es 

10  ftGrayshalv 
30  feet 
Bu/f'UmestoJu: 

lofeet 

192  rcet 
UPPER 
SILURIAN 

27« 

i 

20  feet 
Hard  lUl 

^ 

-500 

1 

78a  reel 

Red.  arid  gray 
sfutlcswim 

jsa  feel                 305 

i 

Gray  sandy 
shalf 
30  feet 

;| 

^ 

295.feet 

Cream- Colo  red 

500- 

'DEVONIAN 

tjS 

ChtOkflintcstone 

131  feet 

1-^ 

maqnesian 

pontus  Umcstone 

■whUe  to  reddish. ) 

Galena  and 

nz 

limestone. 

335 

Tret  Lion 

■t' 

Oalena  and 

limestone 

Trenton 

-rj 

■"^ 

^ 

r^ 

-t. 

te 

^ 

-I— 

— lOO 

600 

^ 

Si 

1 

160  feet 

lied  sandy 

shaU- 
Hudson  tiin'r 

■163 

2. 

20  feet 
Quicksand 

■fs  feel 

3S 

317  reel 
LOWER 

-- r 

438  ffi-t 

LOWER 
'SILURIAN 

-lOO- 

-- 

White  coarse 

SILURIA/V 

■^-i- 

sand 

Ti£ 

500 

^Slate " 

I 

413 

^ 

-300                                                                                                                 ^^- 

1,-1. 
rc 
±s 

sas 

GO-* 

% 

Sandstone 

60  feet 
Red  shale 

WrlBlues/tale 

2 

I. 

546 

& 

St5^eter 
sandstone, 
reddish  and 
white.  Chazy. 

S2  feel 

Shales,  red  to 

300- 

r^ 

ei5 

^ 

intPinksttaU 

P 

gray  and  given, 
\nth  Un-ers  of 

-200 

v; 

^; 

49  feel 

Gmy  gravel. 

J^ 

»-7it/e  sand 
and  guartzitc. 
Loiver  Magnesi/ui 

200- 

^ 

305  feet 

-^^ 

Jortimi  sandstone 

!^. 

Cream-  colored 

ee* 

sae 

I^r"- 

-^ 

ma^ruvian 

r-€ 

46  feel 

64-t 

m 

eft.Gneiss            .r^rHFAN 

lOnestone 

lied  shale 

*£ 

Galena  and 
Trenton 

7P0  /'I'l^l 

110 

S 

t 

-lOO 

LOWER 
SILURIAN 

^ 

tea  feet 
CUiyryshale 

2ae  feet 
UPPER 
■CAMBRIAN 

lOO- 

A€yAt.?f_J"^  -5^^  1   1 

aoo 

§i 

35 

Z:^ 

15  feet 

Qj 

— - 

.^ 

Redstuufy 

< 

^- 

::^ 

shale 

Jg 

'.^ 

E^ 

u 

893 
S03 
SIS 

tM 

^nVresbadi  sands. 

on^ 

eis 

rr: 

a! 

m 

12  feel  Granite           ARCHEAN 

-lOO 

^ 

50  feet 
Softwliite 
sandstoni 

a, 
55 

-lOO- 

P25 

-^ 

^ 

SOfiet 

't; 

Dark  red 
s?iaJc 

a 

575 

^T- 

25feet 
Hod  and 

'00 

■2 

-200 

lOOO 

'020 

i 

green  shale 
.iO  feet 
GrwsfiaJe 

0 

-200- 

I03S 
1031 

S 

Jiedxcuiilvstmlef'^ 
2  f^ei  Gram/.- 

ARCHEAN 

1 

SECTIONS  OF  WELLS  AT  IlL'MBOLDT,  ML\N;  GHi\I<^TON,  XD;  AND  ROSENFELD 

AND  MORDEN,  MANITOBA. 


BIEN   a  CO  N  V 


THE  HUMBOLDT  ARTESIAN  WELL.  75 

east  of  the  river  and  5  miles  south  of  the  international  boundary.  The 
elevation  of  the  surface  is  792  feet  above  the  sea,  being  a  few  feet  above 
the  highest  flood  stage  of  the  Red  River.  On  account  of  the  saltness  of  its 
water,  an  analysis  of  which  is  given  in  Chapter  X,  the  well  is  not  used. 

Prof  N.  H.  Winchell  has-  reported  this  section,^  shown  by  samples  from 
the  boring,  a  summary  of  which  is  as  follows: 

Section  of  an  artesian  tcell,  Humboldt,  Minn. 

Feet. 
Soil  and  very  fine  sandy  day,  stratified 16 

Moistei  and  darker,  more  impervious  clay,  apparently  a  downward  continuation  of 
the  foregoing,  but  probably  including  pebbles  and  bowlders,  at  least  spar- 
ingly, in  its  lower  portion,  being  tbere  bowlder-clay  or  till 124 

Pebbly  blue  till,  containing  salt  water  in  small  quantity  at  165  feet  below  the 

surface 30 

Drift  gravel  and  sand,  mainly  a  gray  sand,  but  containing  pebbles  up  to  an  inch 
in  diameter,  mostly  of  limestone;  supplying  an  abundant  artesian  flow  of 
salt  water 10 

Cream-colored  magnesian  limestone,  of  grain  and  texture  like  the  Lower  Magne- 
sian  in  southeastern  Minnesota  [and  equally  like  the  Galena  or  Upper  Mag- 
nesian and  Trenton  formation  in  Manitoba],  showing  near  its  base  some 
intermixture  of  grains  of  white  quartz 295 

Sandstone,  composed  of  rounded  quartz  grains,  reddish  in  its  upper  part  for  25 
feet,  white  in  its  central  part,  from  both  of  which  the  artesian  flow  of  salt 
water  increased,  and  faintly  reddish  in  its  lowest  10  feet 71 

Shales,  varying  in  color  from  red  and  brown  to  gray  and  green,  with  occasional 
siliceous  layers  that  vary  from  white  sand  to  slightly  calcareous,  grayish 
quartzite 92 

Gneiss  or  granite,  composed  of  opaque  gray  quartz,  flesh-colored  orthoclase,  also 
a  white  feldspar  and  black  mica,  "evidently  one  of  the  Laurentiau  granites 
as  seen  at  the  Lake  of  the  Woods,"  into  which  the  boring  extended 6 

Total GU 

Drift  deposits  here  reach  a  depth  of  180  feet,  below  which  are  458  feet 
of  strata  referable  to  the  Trenton,  Chazy,  and  Calciferous  series  of  the 
Lower  Silurian  system. 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Thirteenth  Annual  Report,  for  1884,  pp.  41-46. 


76  THE  GLACIAL  LAKE  AGASSIZ. 

Next  beneath  the  drift  is  a  thick  formation  of  magnesian  limestone, 
shown  by  comparison  with  the  other  wells  to  be  the  Galena  and  Trenton 
strata,  classed  together  as  one  formation  under  the  second  of  these  names 
by  Whiteaves  and  Tyn-ell,  Avhich  outcrops  at  a  distance  of  75  to  85  miles 
northward,  in  the  ^ncinity  of  Lower  Fort  Garry  and  East  Selkirk,  Mani- 
toba. Its  top  and  bottom  at  Humboldt,  however,  are  respectively  612  and 
317  feet  above  the  sea,  the  entire  formation  here  being  thus  beneath  the 
level  of  Lake  Winnipeg.  In  southeastern  Minnesota,  southwestern  Wis- 
consin, and  adjoining  portions  of  Iowa  and  Illinois,  the  Galena  and  under- 
lying Trenton  limestones  together  range  from  200  to  300  feet  or  more  in 
thickness. 

The  sandstone  next  below,  having  a  thickness  of  71  feet,  is  evidently 
the  equivalent  of  the  St.  Peter  sandstone,  referable  to  the  Chazy  epoch, 
which  in  southeastern  Minnesota  underlies  the  Trenton  limestone,  and 
ranges  in  thickness  there  from  about  75  feet  to  164  feet.  Its  continuation 
in  Wisconsin,  as  described  by  Chamberlin  and  Irving,  averages  probably 
between  80  and  100  feet  thick,  varying  from  a  maximmn  of  212  feet  down 
to  a  fraction  of  1  foot.  In  this  and  adjoining  States,  according  to  Il'^dug, 
it  is  continuous  "over  a  region  whose  diameters  are  500  and  400  miles."^ 

Beneath  tliis  the  Humboldt  well  penetrated  92  feet  of  shales,  partly 
arenaceous  and  calcareous,  which  con-espond  to  the  Lower  Magnesian  or 
Shakopee  hmestone  of  southeastern  Minnesota,  ranging  from  96  feet  in 
thickness  at  Shakopee  to  200  feet  in  Houston  Count}^,  while  in  Wisconsin 
it  is  from  65  to  250  feet  thick.  The  reports  of  the  geological  surveys  of 
these  States  regard  this  formation  as  of  Upper  Cambrian  age,  but  Walcott, 
in  his  more  recent  review  of  the  Cambi-ian,^  assigns  the  Lower  Magnesian 
limestone  wholly  or  mainly  to  the  base  of  the  Lower  Silurian  system.  Its 
eastern  equivalent  is  the  Calciferous  sandi-ock  of  New  York. 

The  entu-e  Cambrian  and  Algonkian  systems  are  wanting  in  this  sec- 
tion, and  the  Lower  Silurian  strata  rest  directly  on  the  Archean  crystal- 
line rocks. 

'  Geology  of  Wisconsin,  Vol.  I,  pp.  145-150;  Vol.  II,  p.  555. 
=  U.  S.  Geol.  Survey,  Bulletin  Xo.  81,  1891,  p.  363. 


THE  GEAFTON  ARTESIAN  WELL.  77 

WELL    AT    GRAFTON,    N.    DAK. 

The  city  of  Grafton  is  also  on  the  Red  River  Valley  plain,  being  situ- 
ated 12  miles  west  of  the  river  and  40  miles  south  of  the  international 
boundary,  at  an  elevation  of  825  feet  above  the  sea.  Its  distance  from 
Humboldt  is  about  38  miles  to  the  south-southwest.  The  following'  record 
of  the  boring  here  was  made  by  the  engineer  in  charge  during  the  prog- 
ress of  the  work,  and  was  supplied  to  me  by  the  mayor,  Mr.  J.  Tombs,  at 
the  time  of  my  visit  to  Grafton  in  the  survey  of  the  shore-lines  of  Lake 
Agassiz.  It  has  been  published  by  the  Dakota  commissioner  of  immi- 
gration.^ 

Section  of  an  artesian  well,  Grafton,  JV.  DaJc. 

Feet. 
Black  loam 3 

White  clay 25 

Blue  clay 250 

Hardpau 20 

Limestone 137 

Quicksaud 20 

White,  coarse  sand 45 

Slate , 3 

Sandstone,  yielding  a  copious  flow  of  brackish  water 25 

Eed  shale 60 

Blue  shale 16 

Pink  shale 11 

Gray  gravel 49 

Eed  shale 46 

Soapstoue  [clayey  shale] 188 

Sandstone,  yielding  a  small  flow  of  very  salt  water 5 

Granite 12 

Total 915 

Glacial  drift,  doubtless  mostly  till,  with  a  thin  covering  of  lacustrine 
and  alluvial  clay,  reaches  to  the  depth  of  298  feet. 

The  limestone  next  encountered,  with  a  thickness  of  137  feet,  evidently 
is  the  lower  portion  of  the  thick  formation  of  limestone  of  Galena  and 

'  Resources  of  Dakota,  1887,  p.  188. 


78  THE  GLACIAL  LAKE  AGASSIZ. 

Trenton  age,  found  next  beneath  the  drift  in  the  Humboldt  well,  its  upper 
part  here  having  been  lost  by  erosion. 

The  St.  Peter  sandstone  occupies  a  thickness  of  93  feet. 

Red,  blue,  and  pink  shales,  representing  the  Lower  Magnesian  forma- 
tion, ensue,  with  a  thickness  of  87  feet. 

The  next  stratum,  49  feet  thick,  is  probably  the  equivalent  of  the 
Jordan  sandstone,  the  highest  division  in  the  St.  Croix  series  of  the  Upper 
Cambrian.  Its  thickness  in  southeastern  Minnesota  ranges  from  40  to  116 
feet,  and  in  Wisconsin,  Avhere  it  is  known  as  the  Madison  sandstone,  it  is 
from  30  to  60  feet  thick. 

The  succeeding  shales,  having  a  thickness  of  234  feet,  appear  to  rep- 
resent the  St.  Lawrence  formation,  the  second  in  the  St.  Croix  series,  which 
in  southeastern  Minnesota  varies  from  128  to  213  feet  in  thickness. 

Beneath  the  shales,  the  thin  bed  of  Avater-bearing  sandstone,  lying  on 
the  granite,  may  be  a  trace  of  the  Dresbach  sandstone,  a  tliird  division  of 
the  St.  Croix,  wliich  has  a  thickness  of  50  to  80  feet  or  more  in  southeastern 
Minnesota.  The  brine  rising  from  this  bed  was  analyzed  by  Prof  Hemy 
Montgomery,  of  the  University  of  North  Dakota,  and  was  found  to  be 
(more  saline  than  sea  water. 

Samples  of  the  borings  in  the  lowest  12  feet  were  submitted  to  Prof 
N.  S.  Shaler,  who  pronounced  them  to  be  granite  or  gneiss,  being  the 
Archean  bed  of  the  ocean  in  wliich  the  overlying  Paleozoic  strata  were 
deposited. 

The  water  used  from  this  well  is  taken  from  the  St.  Peter  sandstone, 
the  lower  part  of  the  bore  having  been  filled.  The  diameter  of  the  pipe  is 
G  inches,  and  the  flow,  according  to  three  measurements  in  1886  and  1887, 
during  the  first  year  after  the  completion  of  the  well,  was  800  gallons  per 
minute. 

WELL    AT    ROSENFELD,   MANITOBA. 

Rosenfeld  is  situated  14  miles  north  of  the  international  boundary  and 
11  miles  west  of  the  Red  River,  being  30  miles  northwest  of  Humboldt, 
and  about  54  miles  distant,  in  a  direction  slightly  west  of  north,  from 
Grafton.     Like  Humboldt  and  Grafton,  it  is  on  the  flat  plain  of  the  Red 


THE  EOSENFELD  ARTESIAN  WELL,  79 

River  Valley,  and  the  elevation  is  the  same  as  at  Humboldt,  within  1  foot, 
the  railway  at  Rosenfeld,  3  feet  above  the  surface  at  the  well,  being-  796 
feet  above  the  sea.  A  summary  of  the  section  of  this  well,  according  to 
records  and  samples  of  the  boring  supplied  by  Mr.  W.  E.  Swan,  who  drilled 
it,^  is  as  follows: 

Section  of  mi  artesian  well,  Rosenfeld,  Manitoba. 

Feet. 

Black  soil 4 

Fine  silt  or  clay,  alluvial  and  lacustrine  in  its  upper  portion,  but  below  probably 

including  a  considerable  thickness  of  bowlder-clay  or  till Ill 

Sand  and  gravel 10 

Bowlder-clay  ("bardpan") 12 

Bowlders 6 

Gray  shale  .  -    62 

Cream- colored  or  buff  limestone 15 

Eed  shale 5 

Gray  shale 10 

Cream-colored  limestone,  beneath  which  was  encountered  a  small  artesian  flow 

of  salt  water 30 

Fine  gray  sandstone  or  sandy  shale 40 

Chalky  limestone,  varying  in  color  from  white  to  pale  greenish  and  reddish  gray.  30 
Eed  shale,  containing  much  subaugular  quartz,  in  grains  which  are  very  irreg- 
ular in  size,  some  being  quite  coarse 160 

Cream-colored  magnesian  limestone,  beneath  which  came  an  additional  artesian 

flow  of  salt  water 305 

Eed  shale,  with  much  quartz  in  subangular  grains 75 

Soft  sandstone,  consisting  of  rounded  and  ijolished  quartz  grains,  white,  but 
reddish  in  the  drillings  fi-om  its  upper  portion,  apparently  because  of 
admixture  of  the  overlying  shale;  yielding  a  large  artesian  flow  of  salt 
water,  the  supply  of  which  was  increased  to  four  times  its  previous  quan- 
tity   50 

Dark-red  shale,  with  greeuish^gray  interlaminations 50 

Eeddish  and  greenish  shale 25 

'Published  by  Prof.  N.  H.  Winchell  in  the  Fourteenth  Annual  Eeport  of  the  Geol.  and  Nat.  Hist. 
Survey  of  Minnesota,  for  1885,  p.  15;  and  by  Dr.  G.  M.  Dawson,  "On  certain  borings  in  Manitoba 
and  the  Northwest  Territory,"  Trans.  Roy.  Soc.  Canada,  Vol.  IV,  sec.  4,  1886,  iip.  85-91.  Dr.  Dawson 
supplements  the  brief  record  kept  by  Mr.  Swan  with  many  descriptive  notes  from  his  examination  of 
the  samples;  and  his  identificatiou  of  the  lower  formations,  which  this  well  has  in  common  with  the 
Humboldt  and  Grafton  wells,  is  here  followed.  The  strata  above  the  Galena  limestone  were  referred 
by  Dawson  wholly  to  the  Hudson  River  epoch;  but  comparison  witli  the  Morilen  well  indicates  that 
they  probably  include  not  ouly  Hudson  River  beds,  but  also  the  Niagara  and  other  Upper  Silurian 
formations,  nearly  or  quite  to  the  base  of  the  Devonian. 


80  THE  GLACIAL  LAKE  AGASSIZ. 

Feet. 

Bluish  and  gray  shale - 20 

Eed  shale  or  clay,  inclosing  much  quartz  sand 15 

Granite  or  gneiss,  chiefly  composed  of  quartz  and  red  feldspar  in  rather  small 

crystals 2 

Total 1,037 

Alluvial  and  lacustrine  silts  and  drift  deposits  reach  a  depth  of  143 
feet,  the  top  of  the  bed-rock  being  60  feet  below  the  level  of  Lake  "Winnipeg. 
Examining  the  succession  of  strata  peneti'ated  below,  we  confidently  recog- 
nize the  thick  limestone  formation  which  extends  between  the  depths  of  495 
and  800  feet  as  the  same  that  is  found  with  nearly  as  great  thickness  in  the 
Humboldt  well.  It  is  referable,  as  Dr.  Dawson  concludes,  to  the  Galena 
limestone,  passing  below  into  the  Trenton.  In  the  distance  of  30  miles 
from  Humboldt  this  limestone  sinks  somewhat  more  than  300  feet,  aver- 
aging between  10  and  11  feet  per  mile.  Comparison  with  the  Grafton  well, 
in  which  the  base  of  this  formation  lies  73  feet  higher  than  at  Hmnboldt, 
indicates  an  approximately  west-northwest  direction  for  the  maximum  dip 
of  the  strata  here,  so  that  probably  they  sink  at  about  the  same  rate,  nearly 
11  feet  per  mile,  in  the  distance  of  24  miles  from  Rosenfeld  west  to  Morden, 
as  from  Humboldt  northwest  to  Rosenfeld.  -Such  inclination  from  the  top 
of  the  section  under  the  drift  at  Rosenfeld  would  coincide  very  nearly  (as 
shown  in  PI.  XV)  with  the  bottom  of  the  Morden  well,  from  which  Mr. 
Tyrrell  reports  fossils  belonging  to  the  lower  part,  probably  the  base,  of 
the  Devonian  series. 

From  these  considerations,  if  appears  that  the  192  feet  of  shales,  lime- 
stones, and  sandstone  shown  by  this  section  next  below  the  drift  must 
represent  the  whole  Upper  Silurian  series  of  this  district,  and  that  the 
lower  100  feet  of  this  thickness  are  probably  the  Guelph  and  Niagara 
formations.  The  lowest  of  these  hmestones,  30  feet  thick,  seems  to  be  the 
equivalent  of  the  limestone  of  Stonewall  and  the  top  of  Stony  Mountain. 

The  Lower  Silurian  series  includes  the  next  160  feet  of  red  shale, 
belonging  to  the  Hudson  River  formation;  the  305  feet  of  Galena  and 
Trenton  limestone;  the  underlying  red  shale  and  St.  Peter  sandstone, 
together  125  feet  thick;  and,  finally,  110  feet  of  shales,  occupying  the  place 
of  the  Lower  Magnesian  limestone. 


THE  CRETACEOUS  AREA.  81 

WELL  AT  MORDEN,  MANITOBA. 

Morden  is  due  west  of  Rosenfeld  at  a  distance  of  24  miles,  lying  on 
the  border  of  the  broad  plain  which  extends  from  the  Red  River  to  the 
Pembina  Mountain.  Its  elevation  is  978  feet  above  the  sea.  A  well, 
reported  by  Tyrrell,  was  drilled  here  to  the  depth  of  600  feet,  during  the 
winter  and  spring  of  1889-90,  with  the  hope  of  obtaining  artesian  water. 
Its  section  was  alluvial  sand  and  fine  gravel,  15  feet;  till,  16  feet;  gray 
Cretaceous  shales,  referred  to  the  base  of  the  Fort  Pierre  formation  and 
the  next  lower  Niobrara  and  Fort  Benton  formations,  289  feet;  the 
white  Dakota  sandstone,  92  feet;  and  red  and  gray  shales,  with  porous 
limestone,  representing,  as  shown  by  their  fossils,  probably  the  base  of  the 
Devonian  system,  188  feet.  The  westward  dip  of  the  strata  in  the  Hum- 
boldt and  Rosenfeld  wells  carries  them  beneath  the  bottom  of  the  Morden 
well.  No  artesian  flow  was  obtained  at  Morden,  but  from  the  top  of  the 
Dakota  sandstone  strongly  saline  water  rose  to  within  6  feet  of  the  surface. 

CRETACEOUS  FORMATIONS. 

Cretaceous  beds-  lie  on  the  west  border  of  the  Archean  rocks  in  Min- 
nesota ;  and  farther  north,  along  the  west  side  of  the  lower  part  of  the  Red 
River  Valley  and  of  Lakes 'Manitoba  and  Winnipegosis,  they  rest  upon,  the 
Lower  and  Upper  Silurian  and  Devonian  strata  that  form  the  floor  of  this 
broad,  flat  valley,  beneath  its  glacial,  lacustrine,  and  fluvial  deposits. 
Thence  northwestward  to  the  Mackenzie  and  the  ocean  Cretaceous  beds 
border  and  overlie  the  west  part  of  the  Silurian  and  Devonian  belt.  West 
of  Lake  Agassiz  the  Cretaceous  area  has  a  width  of  600  to  700  miles, 
including  the  entire  region  of  the  elevated  plains,  and  terminating  at  the 
east  base  of  the  Rocky  Mountains. 

Marine  series  of  the  Upper  Missouri. — In  the  region  of  the  Upper  Mis- 
souri River,  formations  belonging  to  the  middle  and  later  portions  of  the 
Cretaceous  period  are  well  developed.  Meek  and  Hayden  there  identified 
five  members  of  this  system,  in  descending  order  as  follows:^  The  Fox 
Hills  formation,  gray,  feiTuginous,  and  yellowish   sandstone,  and  arena- 

'  Report  of  tlie  U.  S. -Geological  Survey  of  the  Territories,  1870,  p.  87. 
MON    XXV 6 


82  THE  GLACIAL  LAKE  AGASSIZ. 

ceous  shales,  500  feet;  the  Fort  Pierre  formation,  dark-gray  and  bklish 
shales  and  plastic  clays,  700  feet;  the  Niobi-ara  formation,  lead-gray 
calcareous  marl,  passing  down  into  light-yellowish  and  whitish  limestone, 
200  feet;  the  Fort  Benton  formation,  dark-gray  laminated  shales  and  clays, 
sometimes  alternating  near  the  upper  part  with  seams  and  layers  of  soft 
gray  and  light-colored  limestone,  800  feet;  and  the  Dakota  formation, 
yellowish,  reddish,  and  occasionally  white  sandstone,  with,  at  places,  alter- 
nations of  various-colored  shales  and  beds  and  seams  of  impure  lignite,  400 
feet.  Leaves  of  dicotyledonous  trees,  including  many  genera  still  existing, 
are  found  in  the  Dakota  formation;  also  a  few  species  of  fresh-water  or 
brackish-water  and  marine  shells.  The  formations  here  enumerated  above 
this  are  marine  deposits,  as  shown  by  plentiful  fossils  throughout  the 
greater  part  of  the  series. 

More  recent  classifications  by  King,  White,  and  Eldridge  unite  the 
two  members  of  this  series  next  above  the  Dakota,  naming  them  together 
the  Colorado  formation ;  and  in  like  manner  the  succeeding  two  still  higher 
are  united  and  named  the  Montana  formation.^  For  the  purpose  of  the 
present  chapter,  however,  it  will  be  more  convenient  to  use  the  older  desig- 
nations. 

In  the  South  Saskatchewan  basin. — North  of  the  international  boundary, 
the  development  of  these  portions  of  the  Cretaceous  system  in  the  region 
of  the  Bow  and  Belly  rivers,  which  unite  to  form  the  South  Saskatchewan, 
is  reported  by  Dr.  George  M.  Dawson  as  follows :  The  Fox  Hills  sandstone, 
in  some  parts  of  the  district  well  defined  as  a  massive  yellowish  sandstone, 
but  inconstant,  80  feet;  the  Fort  Pierre  formation,  neutral-gray  or  brown- 
ish to  nearly  black  shales,  marine,  750  feet;  the  Belly  River  formation,  an 
extensive  fresh-water  and  brackish-water  series,  consisting  of  sandy  argil- 
htes  and  sandstones,  the  upper  portion  characteristically  pale  in  tint,  the 
lower  generally  darker  and  yellowish  or  brownish,  probably  of  the  same- 
age  with  the  Niobrara  formation,  910  feet;  and  lower  dark  shales,  observed 
on  the  upper  part  of  Milk  River,  regarded  as  representing  the  Fort  Benton 
member  of  the  Upper  Missouri  section,  800  feet.  The  lowest  or  Dakota 
formation  is  not  recognized  in  that  district.      Valuable  beds  of  lignite  are 


'  C.  A..  White,  "  Correlation  Papers — Cretaceous,"  U.  S.  Geological  Survey,  Bulletin  No.  82. 


THE  MANITOBA  ESCARPMENT,  83 

found  ill  the  Belly  River  series  and  at  the  base  and  top  of  the  Fort  Pierre 
formation.  "The  Belly  River  series,"  Dawson  writes,  "appears  to  corre- 
spond precisely  to  that  occupying  a  similar  stratigTaphical  position  on  the 
Peace  River,  and  there  designated  the  Dunvegan  series.  These  indicate 
the  existence  of  a  prolonged  interval  in  the  western  Cretaceous  area  during 
which  the  sea  was  more  or  less  excluded  from  the  region,  and  its  place 
occupied  for  long  periods  by  lagoons  or  fresh- water  lakes."  ^ 

Along  the  Manitoba  escarpment. — The  Cretaceous  series  forming  the 
Manitoba  escarpment  and  underlying  its  base  has  been  recently  studied 
and  described  by  Mr.  J.  B.  Tyrrell,  of  the  Canadian  Geological  Survey.^ 
He  divides  the  Fort  Pierre  formation  into  two  parts,  naming  the  upper  part, 
about  500  feet  in  thickness,  the  Odanah  series.  This  division  "consists 
almost  entirely  of  greenish-gray  clay  shale,  which,  when  wet  and  in  place,  is 
soft  enough  to  be  easily  Cut  with  a  knife,  but  on  diying  becomes  quite  hard 
and  brittle.  It  occupies  all  the  top  of  the  Pembina  and  Riding  mountains, 
but  farther  north  no  exposures  of  this  series  were  seen,  the  country 
throughout  being  very  thickly  covered  Avitli  di-ift.  No  fossils  of  any  Idnd 
were  found  in  this  terrane." 

The  lower  part  of  the  Fort  Pierre  shales,  named  the  Millwood  series, 
also  mainly  about  500  feet  thick,  and  attaining  a  maximum  of  664  feet  in 
the  well  bored  at  Deloraine,  "consists  of  soft,  dark-gi-ay  clay  shales,  with 
nodules  of  ironstone  in  which  many  species  of  typical  Pierre  fossils  have 
been  found.  The  terrane  is  well  exposed  at  Millwood,  18  miles  above  Fort 
Ellice,  on  the  Assiniboine  River,  and  it  may  also  be  seen  in  the  gorges  cut 
by  the  Ochre  and  Wilson  rivers  on  the  northeastern  face  of  the  Riding 
Mountain,  in  the  gorge  of  North  Pine  River  in  the  Duck  Mountain,  and 
*     *     *     on  the  eastern  face  of  Porcu^iine  Mountain." 

The  Niobrara  formation,  as  recognized  by  Tyn-ell  in  Ijorings  on  the 
Vermillion  River  at  the  northeastern  base  of  the  Riding  Mountain  escarp- 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1882-83-84 ;  and  DeBcriptive 
Sketch  of  the  Physical  Geography  .ind  Geology  of  Canada,  1884. 

Sir  William  Dawson,  White.ives,  and  Cope  find  the  fossils  of  the  Belly  Kiver  series  "  identical 
with  those  of  the  Laramie."    Am.  Naturalist,  Vol.  XXI,  p.  171,  Felirnary,  1887. 

2  "The  Cretaceous  of  JIanitoba,"  Am.  Jour.  Sci.  (3),  Vol.  XL,  pp.  227-232,  September,  1890;  and 
" Foramiuifera  and  R.idiolaria  from  the  Cretaceous  of  Manitoba,"  Trans.  Roy.  Soc.  Canada,  Vol.  VIII, 
sec.  4, 1890,  pp.  111-115. 


84  THE  GLACIAL  LAKE  AGASSIZ. 

ment,  and  at  Mordeu  and  Deloraine/  varies  in  thickness  from  128  to  545 
feet.  It  comprises  gray,  principally  calcareous  shales,  with  "a  band  of 
light-gray  chalk,  or  mottled-gray  chalk  marl,  about  200  feet  in  thickness, 
outcropping  along  the  foot  of  the  Porcupine,  Duck,  and  Riding  mountains, 
but  lying  below  what  is  generally  known  as  the  Pembina  escarpment  on 
the  eastern  face  of  the  Pembina  Mountain.  *  «  *  The  Niobrara  is 
generally  harder  and  more  resistant  than  the  terranes  either  above  or  below 
it,  and  it  often  forms  little  abrupt  cliffs  in  the  midst  of  an  otherwise  gently 
sloping  country.  It  is,  however,  by  the  constant  presence  of  great  num- 
bers of  foraminifera  that  this  terrane  can  be  identified  with  the  greatest  ease 
either  in  natural  exposures  or  in  the  mud  or  small  fragments  of  rock  taken 
from  the  wells  bored  with  a  percussion  drill.  These  drillings,  as  a  rule, 
appear  very  uninviting  to  the  geologist,  but  in  the  present  case,  when  they 
are  carefully  washed  free  from  the  impalpable  clay  that  forms  a  large  part 
of  their  bulk,  and  examined  under  the  microscope,  they  are  found  to  deter- 
mine the  Niobrara  horizon  with  almost  as  much  accuracy  as  if  good  hand 
specimens  of  the  rock  had  been  obtained."^ 

In  these  borings  the  Fort  Benton  formation  is  represented  by  a 
stratum  of  gray  shales,  from  105  to  178  feet  tliick,  underlain  by  the 
Dakota  sandstone,  which  had  a  thickness  of  only  19  feet  on  the  Vermillion 
River,  and,  with  interbedded  shales,  was  foimd  to  be  92  feet  thick  at 
Morden,  resting  in  both  these  wells  on  Devonian  strata.  Elsewhere  in  this 
district,  outcrops  of  the  Dakota  sandstone,  and  wells  penetrating  it,  show 
that  its  thickness  ranges  from  50  to  150  feet. 

The  hrachish-  and  fresh-water  Laramie  formation. — The  marine  Creta- 
ceous strata  of  the  Upper  Missouri  country  are  overlain  by  the  highest 
member  of  this  system,  the  Laramie  formation,  which  was  deposited  in 
brackish  and  fresh  water.  This  series  covers  a  broad  belt  in  North  Dakota 
and  Montana,  and  stretches  southward  to  Mexico  and  northwestward  into 
Assiniboia  and  Alberta.  It  is  also  well  developed,  but  with  interruptions, 
along  the  Mackenzie  to  the  Arctic  Sea.  The  paleontologic  characters 
of  the  Laramie  beds  caused  it  to  be  long  held  in  dispute  whether  they 

1  "Three  Deep  Wells  in  Manitoba,"  Trans.  Roy.  Soc.  Canada,  Vol.  IX,  sec.  4, 1891,  pp.  91-104. 
^Trails.  Roy.  Soc.  Canada,  Vol.  VIII,  sec.  4, 1890,  p.  113. 


THE  LAEAMIB  SEEIES.  85 

should  be  classed  with  the  Cretaceous  or  the  Eocene,  since  they  contain 
reptilian  fossils  of  Cretaceous  types,  mollusks  allied  j^artly  with  the  Creta- 
ceous and  partly  with  the  Eocene,  and  a  flora  resembling  that  of  the 
Miocene  in  Europe.  From  the  presence  of  beds  of  lignite  coal,  the  name 
Lignitic  was  formerly  often  applied  to  this  formation. 

In  the  Missouri  and  Saskatchewan  region  the  Laramie  series  consists 
mainly  of  sandy  shales  and  sandstones.  The  similar  strata  in  the  vicinity 
of  the  Bow  and  Belly  rivers,  referred  to  the  Laramie  by  Dawson,  have  a 
thickness  of  5,750  feet,  and  are  wholly  fresh-water  deposits  except  near 
their  base.  On  the  Missouri  River  this  series '  reaches  from  near  Bismarck 
westward  by  Fort  Union  and  across  the  Yellowstone  to  the  Milk  and 
Musselshell  rivers.  At  Sims,  on  the  Northern  Pacific  Railroad,  about  40 
miles  west  of  Bismarck,  it  contains  a  layer  of  lignite  8  feet  thick,  which  is 
extensively  mined.  Northward  the  Laramie  series  occupies  the  upper  por- 
tion of  the  basin  of  the  Souris  or  Mouse  River,  and  forms  the  Missouri 
Coteau  to  the  Canadian  Pacific  Railway  and  the  South  Saskatchewan,  and 
probably  will  be  found  continuous  northwest  along  this  coteau  to  the  North 
Saskatchewan.  Near  the  base  of  Turtle  Mountain,  which  beneath  its  thick 
covering  of  drift  is  an  extensive  outlying  area  of  Laramie  strata,  also  on 
the  Souris,  and  on  the  Bow  and  Red  Deer  rivers,  head  streams  of  the 
South  Saskatchewan,  the  lower  -part  of  this  formation  bears  workable 
seams  of  lignite,  apparently  on  nearly  the  same  horizon  with  the  mine  at 
Sims,  in  the  central  part  of  North  Dakota. 

The  western  plains  a  lacustrine  and  land  area  since  the  early  part  of  the 
Laramie  epoch. — Miocene  conglomerate,  sandstone,  and  sand}-  clays,  of 
fluvial  and  lacustrine  deposition,  are  found  lying  on  the  Laramie  and  other 
Cretaceous  formations  in  the  Hand  Hills,  northeast  of  Red  Deer  River,  and 
in  the  Cy^jress  Hills,  between  the  South  Saskatchewan  and  Milk  ri^•ers. 
They  are  remnants  of  strata  that  probably  once  thinlj^  overspread  consid- 
erable portions  of  the  upper  Saskatchewan  region.  Five  hundred  miles 
southeast  from  the  more  southern  of  these  localities  an  extensive  area  of 
fresh-water  Tertiary  deposits,  of  Miocene  and  Pliocene  age,  begins  on 
White  River,  in  the  southwestern  part  of  South  Dakota,  and  reaches  south- 
ward throug'h  Nebraska  to  western  Kansas.     No  marine  Tertiary  formations 


86  THE  GLACIAL  LAKE  AGASSIZ. 

are  known  in  this  interior  portion  of  the  continent.  Since  the  early  stages 
of  the  Laramie  epoch,  the  bed  of  the  Cretaceous  ocean  now  forming  the 
great  belt  of  plains  that  stretches  west  from  the  lake  district  of  Manitoba, 
the  Red  River  Valley,  and  eastern  Nebraska  and  Kansas,  to  the  Rocky 
Mountains,  has  not  been  submerged  beneath  the  sea. 

FORT    PIERKE    SHALES    WEST    OF    LAKE    AGASSIZ. 

The  ascent  upon  Cretaceous  strata,  at  the  south  a  massive  ridge  and  at 
the  north  a  bold  escarpment,  on  the  western '  border  of  the  valley  in  which 
Lake  Agassiz  lay,  called  in  successive  portions  the  Coteau  des  Prairies, 
Pembina,  Riding,  and  Duck  mountains,  and  the.  Porcupine  and  Pasquia 
hills,  has  mostly  so  thick  and  continuous  a  covering  of  glacial  di-ift  that 
only  few  exposures  of  the  underlying  strata  are  seen,  chiefly  where  chan- 
nels have  been  eroded  by  streams.  Thi'oughout  their  extent  of  800  miles 
the  ridge  and  escarpment  appear  to  consist  .mainly  of  the  Fort  Pierre  for- 
mation, presenting  a  thickness  of  several  hundred  feet  of  dark  shales,  mostly 
soft  and  somewhat  sandy.  Under  the  Fort  Pierre  beds  are  similar  shales 
belono-ino-  to  the  Niobrara  and  Fort  Benton  formations,  succeeded  below  by 
the  Dakota  sandstone.  The  overlying  drift  varies  commonly  from  10  or  20 
feet  to  more  than  100  feet  in  depth. 

Southwestern  Minnesota  and  the  Coteau  des  Prairies. — Outcrops  of  the 
Cretaceous  strata  on  the  Coteau  des  Prairies,  and  in  Minnesota  east  of  this 
highland,  are  rare  and  usually  of  small  extent,  both  in  area  and  in  the 
vertical  thickness  exposed;  but  these  beds  are  also  occasionally  penetrated 
by  wells  near  the  east  base  of  the  coteau,  and  at  the  mission  school,  IJ 
miles  north-northwest  of  the  Sisseton  Agency,  on  the  eastern  slope  of  the 
coteau  and  about  1,500  feet  above  the  sea,  a  well  boring  passed  through 
the  drift  and  entered  soft  shale  or  clay,  probably  the  lower  part  of  the  Fort 
Pierre  formation,  at  the  depth  of  138  feet.  The  outcrops  mentioned  east 
of  the  Coteau  des  Prairies  appear  to  belong  mostly  to  the  lower  divisions 
of  the  Upper  Missouri  series.  They  include  sandstones  of  the  Dakota 
formation  on  the  Cottonwood  River,  from  its  mouth  to  a  distance  ol  30 
miles  west,  yielding  numerous  species  of  fossil  leaves;  beds  of  shale,  with 
thin  seams  of  lignite  and  lignitic  clay,  occurring  in  the  bluffs  of  the  Minne- 


THE  FORT  PIERRE  SHALES.  87 

sota  River  about  15  and  30  miles  northwest  of  New  Ulm,  referred  by  Prof. 
N.  H.  Winchell  to  the  Fort  Benton  formation;  similar  deposits  about  70 
miles  farther  north,  on  the  Sauk  River  in  Stearns  County,  identified  as  this 
formation  by  Meek;  and  shales,  with  layers  of  concretionary  limestone,  in 
the  Minnesota  Valley,  at  the  mouth  of  the  Cottonwood,  close  to  New  Ulm, 
which  Professor  Winchell  refers  provisionally  to  the  Niobrara  formation. 
In  the  western  outcrops  on  the  Cottonwood,  lignite-bearing  shales  and  the 
sandstone  containing  impressions  uf  leaves  occur  together,  and  the  same  is 
true  of  tlie  shales  with  limestone  and  the  leaf-bearing-  sandstone  at  the 
mouth  of  this  river;  so  that  possibly  all  these  beds  on  the  Cottonwood  and 
Minnesota  rivers  may  belong  to  one  formation,  which  must  then  be  the 
Dakota,  according  to  Lesquereux's  determinations  of  its  fossil  leaves. 

There  is  evidence,  however,  that  the  ocean  extended  east  nearly  across 
Minnesota  in  later  stages  of  the  Cretaceous  period,  for  Cretaceous  fossils 
and  shale  have  been  found  in  the  glacial  drift,  apparently  not  far  removed 
from  their  original  beds,  at  Lime  Springs,  Iowa,  less  than  5  miles  south 
from  the  south  line  of  Fillmore  County,  Minn.,  including  sharks'  teeth 
closely  like  Otodus  appendiculahis  Ag.,  bones,  teeth,  and  scales  of  teleost 
fishes,  Ammonites  (two  species),  Ostrea,  Inocercunns,  etc.,  regarded  by  Dr. 
C.  A.  White  as  Upper  Cretaceous,  "as  late  as  any  yet  recognized  in  any 
part  of  North  America."^  A  hundi-ed  and  seventy-five  miles  northwest 
from  this  locality  a  perfect  tooth  of  Otodus  appendicidatus  Ag.  has  been 
found  on  a  sand  bar  near  the  mouth  of  Two  Rivers,  tributary  to  the 
Mississippi,  in  Morrison  County,  Minn.  Other  sharks'  teeth  and  fragments, 
belonging  to  different  species,  have  also  been  found  in  that  vicinity  and 
on  the  south  branch  of  Two  Rivers,  in  Stearns  County,  at  a  distance  of 
about  8  miles  to  the  southwest.  These  indicate  that  marine  Cretaceous 
beds,  probably  of  the  same  age  with  the  fossils  at  Lime  Springs,  underlie 
the  drift  somewhere  in  central  Minnesota;  though  it  is  possible  that  they 
have  been  wholly  eroded,  their  fossils  being  now  contained  in  the  drift.  At 
the  mouth  of  Two  Rivers,  fresh-water  shales,  probably  of  similar  middle 
Cretaceous  age  with  the  lignite-bearing  beds  of  the  Sauk  and  Minnesota 
rivers,   are  exposed  to  the  height  of  a  few  feet  above  the  level   of  the 

I  Proe.  A.  A.  A.  S.,  1872,  Vol.  XXII,  pp.  187-192. 


88  THE  GLACIAL  LAKE  AGASSIZ. 

Mississippi,  containing  Margaritmia  and  TJnio,  with  a  thin  seam  of  lignite 
and  liguitic  clay.  All  the  Cretaceous  deposits  of  western  Minnesota,  except 
in  the  high  Coteaii  des  Prairies,  now  exist  only  as  a  somewhat  thin  and 
often  discontinuous  sheet,  ranging  in  thickness  up  to  maxima  of  probablv 
nowhere  more  than  100  to  300  or  600  feet,  on  the  Archean,  Algonkian,  and 
Silurian  rocks.  They  are  doubtless  remnants  of  the  base  of  a  considerable 
thickness  of  strata,  perhaps  originally  including  the  entii'e  Cretaceous  series 
of  the  Northwest,  from  the  Dakota  to  the  Laramie. 

A  section  of  the  drift  and  Cretaceous  beds  forming  the  eastern  foot- 
slope  of  the  Coteau  des  Prairies  is  reported  by  Prof.  N.  H.  Winchell  from  a 
well  at  Tracy,  about  60  miles  west  of  New  Ulm,  619  feet  above  the  Min- 
nesota River  at  that  place,  and  1,403  feet  above  the  sea-level.  Till  extends 
from  the  siu'face  to  the  depth  of  120  feet;  next  is  fine  gravel,  largely  of 
limestone,  5  feet,  including  also  fine  sand  and  soil-like  matter,  believed  by 
Professor  Winchell  to  be  "a  remnant  of  the  old  soil  which  accumulated  on 
the  Cretaceous  rocks  during  the  Tertiary  age;"  iinder  this  is  fine  blue 
clay,  20  feet;  then  a  second  bed  of  gravel,  20  feet,  containing  pebbles  of 
buff  limestone  and  of  gray  and  dark  or  reddish  quartzite,  also  of  gray 
conglomerate  or  coarse  sandstone,  ranging  in  size  from  an  inch  in  diameter 
to  sand  grains,  with  much  slag  and  traces  of  lignite,  from  which  characters, 
according  to  Professor  Winchell,  this  bed  "can  be  supposed  to  have 
accumulated  on  the  Cretaceous  after  the  withdrawal  of  the  Cretaceous 
ocean,  the  slag  coming  from  the  combustion  of  the  lignites  contained  in 
the  strata."  From  the  bottom  of  this  gravel,  at  the  depth  of  165  feet, 
Cretaceous  beds  of  clay,  shale,  and  sandstone  reach  525  feet,  having  a 
prevailingly  dark  color  for  446  feet,  but  mostly  white  for  the  lower  79  feet. 
In  descending  order,  they  are  fine  blue  clay,  12  feet;  fine  greenish-blue 
sandstone,  20  feet;  dark-gray  shale,  213  feet;  again,  fine  greenish-blue 
sand,  60  feet;  blue  clay  or  shale,  43  feet;  quartzitic  white  sandstone,  with 
concretionary  pyrite,  32  feet;  fine  gray  sandstone,  5  feet;  again,  blue  clay 
or  shale,  30  feet;  a  second  layer  of  quartzitic  and  pyritous  white  sandstone, 
V  feet;  dark,  unctuous,  fine  clay,  24  feet;  white  kaolinic  clay,  becoming- 
reddish,  then  bluish  and  gritty,  8  feet;  white  and  gray  quartz  sand,  partly 
cemented  by  pp-ite  and  mixed  in  its  lower  part  with  kaolinic  clay,  18  feet; 


SOUTHWESTERN  MINNESOTA.  89 

white  kaolin,  clouded  with  blue  clay,  and  containing  some  grit,  25  feet; 
and  white  quartzitic  sandstone,  28  feet,  containing  kaolinic  material  in  its 
lower  part,  "apparently  resulting  from  the  decay  of  grains  of  feldspar 
after  deposition  in  the  sandstone."^ 

The  thickness  of  446  feet  of  principally  dark  beds,  lying  between 
1,238  and  792  feet  above  the  sea,  probably  corresponds  to  the  Fort  Benton 
shales  and  Dakota  sandstone,  containing  lignite  and  impressions  of  leaves, 
on  the  Cottonwood  and  Minnesota  rivers,  where  their  elevation  is  approxi- 
mately 800  to  1,000  feet  above  the  sea.  Under  these  the  thickness  of  79 
feet  of  mostly  Avhite  kaolinic  clay  or  shale  and  sandstone,  constituting  the 
base  of  the  Dakota  formation  here,  appears  to  be  the  same  with  the  deposits 
of  white  and  greenish  clay,  often  sandy  and  gritty,  which  lie  in  water- 
worn  hollows  of  the  Cambrian  strata  along  the  lower  part  of  the  JMinuesota 
River.  These  earliest  Cretaceous'  sediments  were  evidently  derived  from 
erosion  of  decomposed  surfaces  of  the  adjoining  Archean  gneiss  and  granite. 
Not  all  of  this  decayed  and  kaolinized  rock  was  worn  away  then  nor  by 
the  later  erosion  of  the  Glacial  period;  for  at  many  places  in  the  Minnesota 
Valley,  along  the  distance  of  nearly  50  miles  between  Granite  Falls  and 
Fort  Ridgely,  it  forms  the  upper  10  to  20  or  30  feet  of  the  Archean 
outcrops.  At  713  feet  above  the  sea-level  the  Cretaceous  deposits  of  Tracy 
rest  on  reddish  granite  of  Archean  age,  into  which  this  well  Avas  drilled  34 
feet,  to  a  total  depth  of  724  feet. 

In  the  village  of  Browns  Valley,  situated  between  Lakes  Travei'se  and 
Big  Stone,  in  the  channel  of  which  Lake  Agassiz  outflowed  southward,  a 
well  has  been  sunk  to  the  depth  of  465  feet,  extending-  from  975  to  510 
feet,  approximately,  above  the  sea-level.  The  general  surface  on  each 
side  of  this  valley  or  channel  is  about  1,100  feet  above  the  sea,  125  feet  of 
glacial  drift  having  been  eroded  above  the  site  of  the  well.  After  passing 
through  an  undetermined  thickness  of  alluvial  and  drift  deposits,  this  well 
penetrates  dark-bluish,  hard  clay  or  shale  to  the  depth  of  360  feet;  a  black 
layer  of  lignitic  shale,  2  feet;  gravel  and  sand,  alternating  with  layers  of 
blue  clay,  58  feet;  quartzitic  sandstone,  5  feet,  from  above  and  beneath 
which  artesian  flows  of  water  are  obtained;  greenish,  micaceous,  and  kaolinic 

iGeol.  and  Nat.  Hist.  Survey  of  Minuesota.  Fourteenth  Anun.al  Report,  for  1885,  pp.  351-353. 


90  THE  GLACIAL  LAKE  AGASSIZ. 

shale  or  clay,  20  feet;  and  white  aud  gray  sandy  shale  or  sandstone,  20  feet, 
in  which  the  well  stopped,  not  reaching  the  Archean  rocks.^  These  strata 
above  the  source  of  the  artesian  water  are  probably  equivalent  to  the  dark 
beds  of  the  Ti-acy  well,  while  the  lower  strata  correspond  to  the  white  and 
kaolinic  lower  beds  there. 

Comparing  the  elevations  of  the  top  of  the  kaolinic  deposits  in  these 
wells,  there  is  seen  to  be  a  slight  dip  of  the  strata  toward  the  north-north- 
west, amounting  to  about  240  feet  in  the  distance  of  112  miles  from  Tracy 
to  Browns  Valley.  Another  comparison  is  afforded  by  a  well  near  Sleepy 
Eye,  which  is  -45  miles  east  of  Tracy  and  1,034  feet  above  the  sea,  pene- 
trating 182  feet  of  drift;  then  79  feet  of  white  and  gray  Cretaceous  clay, 
containing  one  thin  stratum  of  brownish-red  clay,  together  corresponding 
apparently  to  the  lowest  79  feet  of  the  Cretaceous  beds  in  the  Tracy  well, 
and  lying,  like  those  beds,  on  Archean  red  granite.^  These  observations 
indicate  a  slight  westward  dip,  amounting  to  about  60  feet,  in  the  Creta- 
ceous .  strata  between  Sleepy  Eye  and  Tracy.  The  resultant  inclination 
satisfying  both  these  sets  of  observations  is  a  dip  of  about  3  feet  per  mile 
to  the  northwest,  being  thus  directed  away  from  the  ridge  of  Algonkian 
quartzite,  1,300  to  1,700  feet  above  the  sea,  which  outcrops  in  northern 
Cottonwood  County,  on  the  east  flank  of  the  Coteau  des  Prairies,  and  in 
Pipestone  and  Rock  counties,  on  its  west  side. 

Above  the  strata  thus  far  described,  a  hard,  gray,  somewhat  calcareous 
and  concretionary  sandstone,  probably  representing  the  Niobrara  formation, 
is  seen  in  a  few  low  outcrops  near  Alta  Vista,  in  the  northeast  corner  of 
Lincoln  County,  and  within  7  miles  eastward,  having  an  elevation  approxi- 
mately 1,17.5  to  1,150  feet  above  the  sea.  These  outcrops  are  30  to  35 
miles  northwest  from  Tracy,  and  occupy  nearly  the  same  stratigraphic 
horizon  with  the  gravel  bed,  between  145  and  165  feet  in  depth,  in  the  well 
at  that  place.  The  only  organic  remains  detected  in  this  sandstone  are 
particles  of  lignite  and  traces  of  wood. 

Clay  or  shale,  containing  fossils  characteristic  of  the  Fort  Pierre  and 
Fox  Hills  formations,  the  upper  members  of  the  marine  Cretaceous  series, 
has  been  encountered  in  numerous  instances  by  wells  in  the  same  region, 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Fourteenth  Annual  Report,  p.  14. 
-Ibid.,  p.  15. 


ALONG  THE  SHEYENXE  RIVER.  91 

within  7  miles  north  and  20  miles  southeast  from  Alta  Vista,  along  the  foot 
of  the  steep  eastern  ascent  of  the  Coteau  des  Prairies,  at  elevations  from 
1,150  to  1,250  feet  above  the  sea.  Perhaps  some  of  these  wells  have 
reached  Cretaceous  strata  in  place;  but  others  evidently  have  been  wholly 
in  the  glacial  drift,  containing  disrupted  and  transported  masses  of  Creta- 
ceous shale  with  fossils.  The  frequency  of  these  fossils  in  the  drift  indicates 
that  Upper  Cretaceous  marine  strata  originally  covered  much  of  this  disti'ict 
and  supplied  a  large  part  of  the  drift,  and  that  they  probably  iinderlie  the 
drift  in  the  Coteau  des  Prairies.  The  list  of  fossils  thus  found  includes 
Baculites  ovatus  Say,  Placent'iceras  (^Ammonites)  placenta  Dekay,  both  these 
represented  by  abundant  specimens,  chiefly  fragments;  Scaphites  nicoUetii 
Morton,  Nuciila  canceUata  M.  &  H.,  and  an  Inoceramus  which  may  be  /. 
prohlematicus  Schlot.^  Twenty-five  miles  distant  to  the  southwest  and  west 
the  cre^t  of  the  Coteau  des  Prairies  attains  a  height  of  1,950  to  2,000  feet 
above  the  sea,  rising  800  feet  above  the  outcrops  and  wells  here  noted. 
This  massive  highland,  beneath  its  mantle  of  drift,  which  probably  varies 
from  50  to  250  feet  in  thickness,  doubtless  consists  mainly  or  wholly  of  the 
Fort  Pierre  and  Niobrara  clays  and  shales,  dipping  very  slightly  to  the 
west  and  northwest.  Because  of  the  soft  character  of  these  beds,  they  are 
not  exposed  in  any  projecting  knob  or  ridge;  and  their  resemblance  in 
material  and  color  to  the  bowlder-clay  or  till,  which  is  derived  in  large  part 
from  them,  makes  their  exposures  less  liable  to  be  noticed  if  they  are 
anywhere  cut  into  by  ravines. 

Alone/  the  Sheyenne  Biver. — The  Fort  Pierre  shales  have  plentiful 
exposures  in  the  bluffs  of  the  Sheyenne  River,  from  where  it  flows  by  the 
Cretaceous  hills  west  and  south  of  Devils  and  Stump  lakes,  covered  partly 
with  morainic  drift,  as  described  in  the  next  chapter,  to  the  most  southern 
bend  of  this  river,  where  it  enters  the  area  of  Lake  Agassiz.  A  sheet  of 
till,  varying  from  10  to  50  feet  or  niore  in  thickness,  sometimes  with  over- 
lying beds  of  gravel  and  sand,  forms  the  upper  part  of  the  Sheyenne  bluffs, 
and  their  lower  portion  consists  of  the  dark-gray,  easily  disintegrating, 
sandy  shales  of  this  formation  to  heights  varying  from  50  to  175  feet  above 
the  river.     There  are  many  excellent  sections  of  both  the  shales  and  the 

'Geol.  and  Nat.  Hist.  Survey  of  Miniiesotn.  Fiiinl  Report,  Vol.  I,  1884,     ji.  600. 


92  THE  GLACIAL  LAKE  AGASSIZ. 

drift,  where  the  slope  has  been  so  lately  underiuined  that  the  shale  forms 
continuous  cliffs  from  a  few  hundred  feet  to  a  quarter  or  half  of  a  mile  in 
leng-th. 

Fossils  are  infrequent,  but  would  doubtless  be  detected  in  many  places 
by  careful  search.  On  the  western  slope  of  a  hill,  partially  bared  of  drift 
and  consisting  of  this  shale,  near  the  west  line  of  section  33,  township  139 
north,  range  58  west,  8  miles  south  of  Valley  City  and  about  IJ  miles  west 
of  the  Sheyenne,  I  found  Inoceranius  sagensis  Owen,  fragments  of  other 
lamellibranchs,  and  Baculites  ovatus  Say.  These  were  on  nearly  the  aver- 
age level  of  the  surrounding  country,  at  a  height  of  about  175  feet  above 
the  river,  or  1,350  feet  above  the  sea. 

In  the  vicinity  of  the  southern  bend  of  the  Sheyenne  are  scanty 
exposures  of  Cretaceous  beds  which  contain  lignite  and  may  belong  to 
the  Fort  Benton  formation.     The  lowest  outcrop,  situated  just  Avithin  the 

* 

highest  shore-line  of  Lake  Agassiz,  is  in  the  southeast  quarter  of  section 
32,  township  135,  range  54, .about  20  rods  west  of  Edward  Bowden's 
house.  Here  the  east  or  right  bank  of  the  Sheyenne  shows  the  following 
section,  in  descending  order :  Soil  and  gray  clay,  with  slight  intermixture 
of  gravel,  2  to  3  feet;  very  coarse  iron-rusty  gravel,  from  1  inch  to  1  foot 
thick,  containing  cobbles  of  limestone,  granite,  and  a  partly  decayed  gneiss, 
of  all  sizes  up  to  6  and  12  inches  in  diameter;  gray  till,  very  compact,  1  to 
IJ  feet;  fine  gravel  and  sand,  about  G  feet,  containing  in  some  portions 
very  plentiful  flakes  and  fragments  of  lignite  from  an  eighth  of  an  inch  to 
2  or  3  inches  long;  and  hard,  dark-bluish  Cretaceous  shale,  seen  only 
to  the  depth  of  a  few  feet  and  hidden  below  by  the  talus,  containing  near 
its  top  a  layer  of  lignite  about  3  inches  thick,  at  the  height  of  25  or  30 
feet  above  the  river,  and  approximately  1,060  feet  above  the  sea.  Springs 
issue  from  the  river  bank,  a  few  rods  farther  southeast,  at  the  top  of  this 
shale.  Mr.  Bowden  reports  another  outcrop  of  a  thin  seam  of  lignite,  per- 
haps belonging  to  the  same  layer,  some  8  miles  distant  from  this  toward 
the  south-southwest,  occurring  in  a  ravine  tributary  to  the  Sheyenne,  about 
a  mile  west  of  its  most  southern  bend.  From  the  second  to  the  first  of 
these  localities  the  river  falls  20  feet,  and  these  outcrops  of  lignite  differ 
little  in  their  elevation  above  the  sea-level. 


PLATEAU  OF  PEMBINA  MOUl^TAIK.  93 

In  the  escarpment  and  plateau  of  Pembina  ^fountain. — Sections  cut  by 
the  head  streams  of  the  Goose  and  Turtle  rivers,  in  the  highland  between 
the  Red  River  Valley  and  Devils  Lake,  and  the  similar  erosion  of  the 
Pembina  Mountain  by  the  branches  of  Park  River  and  by  the  Toiague, 
Little  Pembina,  and  Pembina  rivers,  show  that;  beneath  the  drift,  this  long 
escarpment  and  the  plateau  which  it  bounds  consist  of  dark,  sandy  shale, 
horizontal  or  nearly  so  in  stratification,  and  nearly  uniform  in  character  for 
a  great  thickness.  Gravel  of  this  shale  abounds  in  the  channels  of  the 
sti'eams  for  many  miles  east  of  the  escarpment,  and  is  found  sparingly  in 
the  drift  southward  to  the  Coteau  des  Prairies.  It  is  commonly  called 
"slate"  by  the  people  of  this  region;  but  no  portions  observed  possess 
the  hardness  and  texture  deserving  this  name,  and  no  slaty  cleavage  is 
exhibited. 

The  highest  outcrops  of  this  formation  seen  by  me,  close  to  the  west 
shores  of  Lake  Agassiz,  are  on  the  plateau  that  extends  westward  from  the 
top  of  the  Pembina  Mountain,  where  this  is  channeled  by  the  North  Branch 
of  Park  River  in  the  vicinity  of  Milton.  Along  a  distance  of  5  miles  from 
northwest  to  southeast  through  the  north  part  of  township  159  north,  range 
57  west,  this  stream  cuts  75  to  125  feet  into  the  shale,  its  top  being  1,500 
to  1,550  feet  above  the  sea.  It  is  overlain  by  only  5  to  25  feet  of  till, 
which  continues  equally  thin,  as  shown  by  watercourses  and  wells  pene- 
trating to  the  shale,  for  15  to  30  miles  westward  and  northwestward,  and, 
excepting  two  or  three  morainic  belts,  upon  all  the  country  southwest  to 
Devils  Lake.  The  surface  about  Milton  is  moderately  undulating  and 
rolling,  with  the  crests  of  its  higher  jDortions  25  to  40  feet  above  the 
depressions.  From  this  plateau  an  irregular  descent,  amounting  to  about 
100  feet  per  mile,  occupies  the  east  part  of  this  township  and  the  edge  of 
that  next  east,  falling  in  3  miles  to  the  upper  shore-line  of  Lake  Agassiz, 
which  here  is  approximately  1,200  feet  above  the  sea. 

The  deepest  part  of  the  gorge  of  the  North  Branch  of  Park  River  is  in 
sections  4,  9,  and  10,  township  159,  range  57,  where  it  is  125  to  150  feet 
deep  and  from  a  quarter  to  a  half  of  a  mile  wide,  with  numerous  fine 
exposures  of  the  shale  from  the  base  to  the  top  of  the  bluft's,  exce})t  the  thin 
capping  of  drift.     In  these  places  the  stream,  flowing  at  the  base  of  the 


94  THE  GLACIAL  LAKE  AGASSIZ. 

bluff,  removes  the  talus  which  elsewhere  conceals  its  lower  portion,  and  the 
section  rises  with  cliff-Hke  steepness  at  an  angle  of  60°  to  75°.  Excepting 
occasional  thin  beds,  the  whole  thickness  of  the  formation  here  exposed  is 
hard  gray  shale,  more  or  less  sandy,  divided  into  layers  from  an  eighth  of 
an  inch  to  2  or  3  inches  thick,  and  much  jointed,  so  that  it  crumbles  into 
small  fragments  on  the  weathered  surface.  Rarely  a  bed  a  few  inches  thick, 
having  the  general  dull-gray  color,  is  harder  and  less  jointed,  owing  to  its 
cementation  by  carbonate  of  lime;  and  occasionally  the  ordinary  shale  is 
blackened  by  the  deposition  of  iron  rust  and  of  manganese  oxide  as  films 
in  the  jointage  seams,  the  thickness  of  the  portion  thus  colored  being  usually 
only  a  few  inches,  but  in  one  place,  half  way  up  the  north  bluff,  3  or  4  feet. 
Gypsum  was  observed  only  in  minute  crystals  in  thin  fissures  coinciding 
with  the  planes  of  stratification,  and  in  the  form  of  satin  spar,  filling  the 
mold  from  which  some  shell,  commonly  Inoceramus,  has  been  dissolved 
away.  FossiLs  are  ver}^  infrequent,  but  by  careful  seai-ch  BacuUtes  ovatus 
Say  and  Scaphites  nodosus  Owen  were  found,  each  represented  by  a  single 
specimen;  also  numerous  Inoceramus  casts,  mostly  I.  sagensis  Owen,  besides 
casts  and  fragments  of  other  lamellibranchs,  not  yet  identified;  and  the 
teeth  of  fishes,  apparently  Pachyrlmodus  latimentimi  Cope  and  Lamna  mudgei 
Cope,  or  a  smaller  species.^  The  teeth  occur  somewhat  plentifully  in  a 
remarkably  hard  layer,  6  inches  to  a  foot  thick,  about  50  feet  above  the 
stream.  With  them  this  hard  layer  contains  softer  lumps,  of  somewhat 
irregular  form,  from  one-third  to  three-quarters  of  an  inch  in  diameter, 
of  light-gray  color  inside,  with  a  greenish  exterior,  which  are  probably 
coprolites.  The  other  fossils  were  found  in  the  shale  fragments  forming 
the  talus,  and  their  place  in  the  section  was  not  ascertained.  Although 
few,  they  supply  decisive  evidence  that  this  is  the  Fort  Pierre  formation. 

The  lowest  exposure  of  this  shale  observed  along  the  course  of  the 
Pembina  Mountain  in  North  Dakota  is  21  miles  north  of  the  preceding,  on 
the  Pembina  River,  at  the  "fish  trap,"  a  rude  weir  of  brush  and  poles,  in  the 
northeast  corner  of  the  northwest  quarter  of  section  30,  township  163, 
rano-e  57.     Here  the  river  falls  7i  feet  in  about  40  rods,  its  elevation  being 


■For  aid  in  the  identification  of  tbese  fossils,  and  of  those  collected  on  the  Pembina  River,  I  am 
indebted  to  Dr.  C.  A.  White,  of  this  .Survey. 


FORT  PIERRE  FOSSILS.  95 

estimated'  about  1,060  feet  above  the  sea.  On  each  side,  within  a  mile,  the 
plateau  of  the  Pembina  Mountain,  which  the  river  cuts  through,  rises  400  to 
450  feet  higher.  A  bluff  150  feet  high  ascends  steeply  from  the  fish  trap 
on  the  southwest  side,  and  at  the  time  of  my  first  Adsit,  in  August,  1885,  was 
newly  exposed  by  slides,  being  shown  to  he  fissile,  dark-gray  shale  to  the 
height  of  100  feet,  capped  by  glacial  drift.  The  shale  of  this  lower  jjart  of 
the  Fort  Pierre  formation  is  more  sandy,  softer,  and  darker  than  that  of  its 
upper  part,  seen  on  the  North  Branch  of  Park  River,  and  it  further  differs 
noticeably  in  having  few  joints.  It  is  horizontally  laminated,  and,  where 
it  has  been  somewhat  dried  on  the  surface  of  the  bluff',  is  easily  separated 
in  layers  from  a  quarter  of  an  inch  to  1  inch  thick;  Ijut  at  a  depth  of  only 
2  or  3  feet  within  its  mass,  where  it  is  moist,  no  lamination  is  discernible. 
In  this  shale  crystals  of  selenite  2  or  3  inches  long  are  frequent,  and  the 
same  mineral  occurs  in  its  crevices  and  seams.  No  lignite  is  found  here, 
nor  in  any  of  the  other  outcrops  of  this  formation  along  the  whole  extent 
of  the  Pembina  Mountain  to  the  south  and  north. 

My  second  visit  to  this  locality  was  made  in  August,  188G,  to  search  for 
fossils,  though  none  were  found  the  year  before.  Only  the  upper  20  feet  of 
the  shale  was  visible  in  place  at  this  later  time,  as  the  lower  part,  previously 
exposed  ahnost  to  the  level  of  the  nver,  was  concealed  by  the  talus  of  fallen 
shale  and  dinft.  A  portion  of  the  shale  beds  2  to  3  feet  thick,  about  10  feet 
below  their  top  in  this  section  and  90  feet  above  the  river,  not  distinctly 
contrasted  in  color  or  texture  with  the  beds  above  and  below,  was  found 
to  have  an  odor  resembling  that  of  petroleum,  and  to  contain  sparingly, 
on  the  planes  of  bedding,  impressions  of  ScapJiites  nicoUefii  Morton,  of 
which  about  a  dozen  specimens  were  collected,  and  occasional  casts  and 
fragments  of  Inoceramus  and  Ostrea  species,  one  being  probably  Inoceramus 
sagensis  Owen.  From  a  mass  of  shale  in  the  talus  numerous  cycloid  fish 
scales,  and  a  vertebral  bone,  If  inches  in  diameter,  belonging  to  some 
selachian  fish,  were  obtained.  If  the  formation  is  level  in  its  stratification 
from  south  to  north,  as  seems  to  be  the  case,  this  outcrop  presents  a  portion 
of  it  approximately  200  to  300  feet  lower  than  the  bottom  of  its  exposures 
on  the  North  Branch  of  Park  River. 


96  THE  GLACIAL  LAKE  AGASSIZ. 

About  three-quarters  of  a  mile  east  from  the  fish  trap,  this  snale  is 
exposed  to  a  height  of  75  feet  above  the  Pembina  River  in  a  bluff  on  its 
northeast  side.  Its  highest  outcrop  examined  by  me  in  this  vicinity  is 
Heart  Mound/  a  peculiar  hillock  with  very  steep  sides  and  smoothly 
rounded  top,  situated  on  a  broad,  uneven  terrace  of  Pembina  Mountain, 
near  the  center  of  section  6,  township  163,  range  57,  3^  miles  north  of  the 
fish  trap  and  2  miles  south  of  the  international  boundary.  The  base  and 
top  of  this  hillock  are,  respectively,  about  1,360  and  1,390  feet  above  the 
sea.  Some  have  erroneously  supposed  it  an  artificial  mound.  Glacial 
drift,  containing  granitic  bowlders  up  to  4  or  5  feet  in  diameter,  thinly 
covers  its  northeast  side;  but  the  other  sides  and  the  crest  of  this  knob 
consist  of  shale  similar  to  that  on  the  North  Branch  of  Park  River,  show- 
ing that  it  is  an  outlier  of  the  Fort  Pierre  beds  that  form  higher  land,  drift- 
covered,  about  a  mile  westward.  Heart  ]\Iound  has  been  left  thus  isolated 
by  the  erosion  of  these  beds  from  the  surrounding  area. 

The  thickness  of  the  Fort  Pierre  formation  in  the  northeast  part  of 
North  Dakota,  according  to  these  observations,  is  at  least  300  or  400  feet; 
but  it  doubtless  considerably  exceeds  this,  for  there  is  no  indication  that 
these  exposures  mark  its  upper  and  lower  limits.  Wells  in  Langdon,  17 
miles  northwest  of  Milton  and  1,610  feet  above  the  sea,  after  passing 
through  only  12  to  15  feet  of  till,  enter  this  shale.  With  the  underlying 
Niobrara  and  Fort  Benton  formations,  which  in  this  part  of  the  State  differ 
little  in  lithologic  characters  from  the  Fort  Pierre,  a  thickness  of  1,403  feet 
of  dai;k-gray  shales  was  penetrated  by  the  Devils  Lake  artesian  well 
before  reaching  the  top  of  the  Dakota  sandstone,  which  there  is  39  feet 
above  the  sea-level.  In  Fort  Pierre  outcrops  on  the  North  Branch  of 
Turtle  River,  1^  miles  north  of  Niagara  and  about  1,375  feet  above  the  sea, 
Baculites  ovatus  Say  was  found  in  abundance.  The  eroded  eastern  edge  of 
the  Fort  Pierre  shale  forms  the  long,  high  escarpment  of  the  "Second" 
Pembina  Mountain,  as  the  eroded  border  of  the  Pembina  delta  at  Walhalla 
forms  the  almost  equally  notable,  though  much  shorter,  "First  Mountain." 

'Commonly  called  by  Engli8h-s]ieakiiig  immigrants  "the  Indian  Mound,''  but  more  properly 
named  as  above,  in  accordance  with  the  usage  of  the  Trench  voyagers  and  residents,  who,  probably 
translating  the  aboriginal  name,  call  this  mound  and  the  small  area  of  prairie  around  it  La  Baie  du 
Cceur. 


THE  NIOBEARA  FORMATION.  97 

But  till  or  bowlder-clay,  containing  frequent  granitic  bowlders  up  to  5  or 
sometimes  8  feet  in  diameter,  thinly  covers  the  shale,  so  that  good  expos- 
ures of  it  are  rarely  seen,  excepting  in  the  bluffs  cut  by  streams. 

In  western  Manitoba  and  Assinihoia. — Dr.  George  M.  Dawson  gives  the 
following  summary  of  observations  of  the  Cretaceous  formations  in  the 
district  bordering  the  west  side  of  Lake  Agassiz  north  of  the  international 
boundary,  as  obtained  in  the  Geological  Sm-vey  of  Canada: 

The  character  and  thickness  of  the  different  members  of  the  Cretaceous  in  the 
Manitoba  region  have  not  been  worked  out  in  detail,  owing  to  the  extent  of  the  drift 
covering  and  scarcity  of  sections.  *  *  *  In  the  flat  country  of  the  Eed  River 
Valley  no  exposures  of  the  Cretaceous  rocks  are  found,  and  it  is  below  the  alluvium 
of  this  region  that  the  older  subdivisions  probably  occur.  The  western  margin  of 
the  valley  is  formed  by  the  escarpment  of  the  second  prairie  steppe,  and  here,  in  the 
so-called  Pembina  Mountain,  and  in  its  continuation  to  the  northwestward,  the 
Cretaceous  beds  are  first  met  with.  About  25  miles  north  of  the  forty-ninth  j)arallel, 
where  the  Boyue  River  cuts  through  the  Pembina  escarpment,  beds  clearly  referable 
to  the  Niobrara  group  are  known  to  occur,  and  precisely  resemble,  both  lithologically 
and  in  their  included  fossils,  those  of  the  corresponding  Nebraska  division.  The  rock 
is  generally  a  cream-colored  limestone,  chiefly  composed  of  shells  of  Inoveramus  and 
Ostrea  conyesla,  but  in  places  a  white  chalky  material,  which  under  the  microscope  is 
resolved  into  a  mass  of  foraminiferal  shells,  coccoliths,  and  allied  minute  organisms. 
This  exposure,  though  probably  small  in  extent,  enables  the  outcrop  of  the  Niobrara 
to  be  defined  at  a  point  nearly  400  miles  beyond  the  farthest  northern  locality  known 
previous  to  its  discovery.  Still  farther  north,  along  the  outcrop  of  the  Cretaceous, 
at  Swan  River  and  Thunder  Hill,  west  of  Lake  Winnipegosis,  limestones  and  marls 
containing  fossils  like  those  of  the  last-mentioned  locality,  and  evidently  of  Niobrara 
age,  are  again  found,  and  other  outcrops  of  these,  and  possibly  of  older  beds,  may 
probably  be  discovered  in  this  vicinity. 

With  these  exceptions,  however,  the  Cretaceous  rocks  known  to  occur  between 
the  Eed  Eiver  Valley  and  the  Lignite  group  of  the  Souris  region  belong  exclusively  to 
the  Pierre  group  of  the  Cretaceous,  while  the  Fox  Hill  group,  which  should  intervene 
between  this  and  the  lignite-bearing  series,  has  not  in  this  district  been  recognized, 
and  is,  not  improbably,  but  feebly  developed.  The  Pierre  rocks  *  *  *  consist  of 
dark-colored  grayish,  bluish,  or  blackish  shales,  generally  homogeneous  in  character 
through  great  thicknesses,  and  seldom  containing  fossils  of  any  kind,  though  frequently 
charged  with  selenite  crystals  and  hoMing  nodular  layers  of  poor  limestone.  Expos- 
ures of  these  beds  are  found  in  the  Pembina  escarpment  on  the  Pembina  Eiver  and 
its  tributaries,  and  on  the  Assiniboine,  wliere  the  thick  drift  deposits  have  been  cut 
through.  The  clays  or  shales  are  generally  quite  characteristic  in  api)earance,  and 
MON  XXV 7 


98  THE  GLACIAL  LAKE  AGASSIZ. 

where  they  are  found  it  may  be  taken  for  granted  that  the  lignite-bearing  formation 
has  either  been  removed  by  deniadation  or  has  from  the  first  been  wanting.  Though 
usually  in  appearance  quite  horizontal,  these  beds  must  have  a  slight  westerly  dii), 
which  carries  them  beneath  the  Lignite  group  of  the  Souris  Eiver.' 

Since  this  was  written,  Mr.  J.  B.  Tyrrell  lias  examined  the  Fort  Pierre, 
Niobrara,  and  Lower  Ci'etaceous  formations  in  this  district,  as  ah-eady  cited, 
and  has  determined  their  thicknesses,  chiefly  made  known  by  deep  well 
borings.  Rocks  belonging  to  the  Niobrara  formation  have  also  been 
examined  and  described  by  Director  Selwyn,  of  the  Geological  Survey  of 
Canada,  on  the  southeast  or  right  bank  of  the  Assiniboine,  in  section  36, 
township  8  north,  range  11  west,  about  4  miles  east  from  the  mouth  of  the 
Cypress  River,  at  an  elevation  approximately  950  feet  above  the  sea.  "The 
outcrop  extends  along  the  bank  of  the  river  for  about  500  yards,  and  con- 
sists of  beds  of  highly  fossiliferous  sandy  limestones,  brown  freestone,  and 
dark,  almost  black,  soft  shales.  The  sandstone  and  limestone,  when  broken 
or  struck,  emit  a  strong  odor  of  petroleum."^ 

From  my  own  notes  of  this  locality  I  may  add  that  the  most  conspicu- 
ous sti'atum,  in  which  some  quarrying  has  been  done,  is  a  light-yellowish, 
hard,  sandy  limestone,  exposed  from  the  lt>w-water  line  of  the  river  to  a 
height  of  about  8  feet.  It  is  horizontally  stratified  in  layei's  from  an  inch 
to  a  foot  in  thickness.  Fossil  shells,  chiefly  Ostrea  congesta  Com-ad,  occur 
frequently  tlu-oughout  its  whole  thickness,  being  most  abundant  3  or  4 
feet  below  its  top,  where  they  sometimes  form  nine-tenths  of  the  rock. 
With  these  are  occasional  specimens  of  Belemnitella  manitohensis,  a  species 
recently  described  by  Mr.  Whiteaves.^  This  stratum  along  the  greater  part 
of  its  extent  is  overlain  by  till  20  feet  or  more  in  thickness,  which  in  turn 
is  overlain  by  the  delta  deposits  of  gravel  and  sand  that  the  Assiniboine 
here  brought  into  the  west  side  of  Lake  Agassiz.  But  at  the  south  end  of 
its  exposure,  where  the  limestone  sinks  beneath  the  river,  it  is  seen  to  be 
conformably  overlain  along  a  distance  of  some  25  rods  by  soft,  dark  shale, 
probably  the  base  of  the  Fort  Pierre  formation,  portions  of  which  contain 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1879-80,  pp.  14, 15  A. 

=  Ibid.,  Annual  Report,  new  series,  Vol.  I,  for  1885,  p.  38  A. 

^Ibid.,  Contributions  to  Canadian  Palaeontology,  Vol.  I,  p.  189,  PI.  XXVI,  1889. 


PILOT  AND  STAR  MOUNDS.  99 

very  abundant  casts  of  Inoceramus  prohlematicus  Schlot.     Scales  of  fishes 
are  also  found  in  both  the  limestone  and  shale.  ^ 

The  Tiger  Hills,  extending-  westward  from  the  north  end  of  the  Pem- 
bina Mountain,  consist  of  the  Fort  Pierre  shales,  eroded  in  massive  rounded 
elevations  and  overlain  by  drift  from  a  few  feet  to  50  feet  or  more  in  thick- 
ness, much  of  which  has  the  rough  contour  and  abundant  bowlders  char- 
acteristic of  terminal  moraines.  Thence  southward  to  the  international 
boundary  the  shale  is  frequently  encountered  at  moderate  depths  in  digging 
wells ;  and  here  and  there  remnants  of  its  highest  beds  form  isolated  hills, 
which  show  that  much  erosion  has  taken  place  during  a  former  baselevel- 
ing  of  the  surrounding  plain  country.  Pilot  Mound,  in  section  20,  town- 
ship 3,  range  11,  about  a  third  of  a  mile  in  diameter  at  its  base  and  rising 
steeply  80  feet  above  the  general  level  to  a  rounded  summit  about  1,630 
feet  above  the  sea,  thus  consists  of  the  hard  upper  portion  of  this  shale 
formation,  thinly  covered  with  drift.  Star  Mound,  a  more  massive  and 
moderately  sloping  elevation,  situated  in  sections  22,  23,  26,  and  27,  town- 
ship 1,  range  10,  about  15  miles  southeast  of  Pilot  Mound,  is  of  the  same 
character.  The  base  of  this  hill  extends  three-fourths  of  a  mile  from  east 
to  west  and  a  third  of  a  mile  or  more  from  north  to  south ;  and  it  rises 
with  a  very  regular  oval  form  to  a  small  plain  30  to  40  rods  long  from 
east  to  west  and  half  as  wide  at  its  top,  which  is  100  feet  above  the  adjoin- 
ing country  and  about  1,650  feet  above  sea-level. 

At  the  Niobrara  outcrop  on  the  Assiniboine  the  base  of  the  Fort  Pierre 
formation  is  about  950  feet  above  the  sea ;  on  the  Vermillion  River  it  is 
stated  by  Tyrrell  to  be  at  1,205  feet ;  and  on  the  Swan  River  it  is  probably 
not  higher  than  1,200  or  1,300  feet.  Above  these  elevations  the  Fort  Pierre 
shales  form  the  upper  portion  of  Ridiiig  and  Duck  mountains  and  of  the 
Porcupine  and  Pasquia  hills,  reaching  to  the  depth  of  several  hundi-ed  feet 
beneath  the  glacial  drift  along  the  entire  course  of  this  great  escarpment. 

The  records  of  common  and  artesian  wells  in  Chapter  X  contain 
further  notes  of  the  Cretaceous  formations  underlying  the  drift  on  the  Red 

•My  thanks  are  due  to  Mr.  J.  F,  Whiteaves,  of  the  Canadian  Geological  Survey,  for  his  kind 
assistance  in  the  identification  of  these  fossi  Is.  A  series  of  the  variable  small  Ostrea  obtained  at  this 
locality,  and  from  the  same  formation  on  the  Boyne  and  in  the  district  of  the  Riding  and  Duck  moun- 
tains and  northward,  was  submitted  by  him  to  Dr.  C.  A.  White,  who  refers  them  to  0.  (.■ovgesta  Conrad. 


100  .  THE  GLACIAL  LAKE  AGASSIZ, 

River  Valley  plain  south  and  southwest  of  the  Silurian  area.  Tracts  of  the 
Dakota  sandstone  probably  supply  the  brackish  water  which  is  found  by 
many  wells  in  this  valley,  similar  to  the  water  derived  from  this  sandstone 
by  deep  artesian  wells  at  Tower  City  and  Devils  Lake,  along  the  James 
River,  and  on  higher  land  in  South  Dakota  west  of  the  James  Valley. 


FORMER  EXTENT  OF  CRETACEOUS  BEDS  EASTWARD  ON   THE  AREA 

OF  LAKE  AGASSIZ, 

East  from  the  foot  of  the  highlands  of  Pembina,  Riding,  and  Duck 
mountains  and  the  hills  farther  north.  Cretaceous  strata  have  not  been 
found,  so  far  as  I  have  learned,  in  Manitoba,  nor  in  the  region  north  and 
northeast  from  Lake  Winnipeg  to  Hudson  Bay.  It  seems  quite  certain, 
however,  that  Cretaceous  beds  continuous  from  this  escarpment  originally 
extended  east  a  considerable  distance,  probably  so  far  as  to  cover  the  area 
now  occupied  by  Lake  Winnipeg.  As  Hind  and  Dawson  have  pointed  out, 
it  was  by  the  erosion  of  their  eastern  portion  that  this  steep  line  of  high- 
lands was  formed ;  ^  and  it  may  be  expected  that  thin  remnants  of  them 
will  yet  be  found  in  central  and  eastern  Manitoba. 

The  eastward  continuation  of  the  Cretaceous  formations  in  southern 
and  central  Minnesota,  indicated  by  numerous  outcrops,  has  been  noticed  in 
the  preceding  pages.  Further  evidence  of  their  former  extent  is  afforded 
in  the  north  part  of  this  State  by  Mr.  Horace  V.  Winchell's  discovery  of 
Cretaceous  shales  in  place  on  the  Little  Fork  of  Rainy  River,  ^  and  by  the 
frequent  occurrence  of  lignite  in  the  drift  upon  the  country  south  of  the 
Lake  of  the  Woods  and  between  Rainy  Lake  and  Vermilion  Lake.  Possi- 
bly this  lignite  may  be  of  interglacial  age,  like  beds  that  are  found  between 
deposits  of  till  in  southeastern  Minnesota,  in  the  basin  of  the  Moose  River, 
tributary  to  James  Bay,  and  in  other  places;  but  Prof  N.  H.  Winchell 
thinks  that  more  probably  its  origin  is  from  lignite-bearing  Cretaceous 

'  H.  Y.  Hind,  Report  of  the  Assiniboine  and  Saskatchewan  Exploring  Expedition,  Toronto,  1859, 
pp.  168, 169;  Narrative  of  the  Canadian  Exploring  Expeditions,  London,  1860,  Vol.  II,  pp.  48,55,  and 
265.     G.  M.  Dawson,  Geology  and  Eeeources  of  the  Forty-ninth  Parallel,  1875,  pp.253,  254. 

2  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Sixteenth  Annual  Report,  for  1887,  pp.  403-9,  431, 434. 


SOUECES  OF  THE  CRETACEOUS  DEPOSITS.  101 

strata  such  as  outcrop  on  the  Sauk  and  Minnesota  rivers.     Concerning-  the 
eastern  hmits  of  Cretaceous  beds  in  this  State  he  writes : 

A  line  drawn  from  the  west  end  of  Hunters  Island,  on  the  Canadian  boundary 
line,  southward  to  Minneapolis,  and  thence  southeastwardly  through  Eochester  to 
the  Iowa  State  line,  would,  in  general,  separate  that  part  of  the  State  in  which  the 
Cretaceous  is  not  known  to  exist  from  that  in  which  it  does.  It  is  not  intended  to 
convey  the  idea  that  the  whole  State  west  of  this  line  is  spread  over  with  the  Creta- 
ceous, because  there  are  many  places  where  the  drift  lies  directly  on  the  Silurian  or 
earlier  rocks,  but  throughout  this  part  of  the  State  the  Cretaceous  exists  at  least  in 
patches,  and  perhaps  once  existed  continuously.' 

SOURCES    OP    THE    CRETACEOUS    DEPOSITS. 

Deposits  of  Cretaceous  clay  are  found  in  waterworn  hollows  of  the 
Lower  Magnesian  or  Shakopee  limestone  forming  the  walls  of  the  channel 
or  valley  of  the  Minnesota  River  at  numerous  places  in  Blue  Earth,  Le 
Sueur,  and  Nicollet  counties.  It  is  thus  known  that  before  the  Cretaceous 
period,  when  western  Minnesota  and  the  region  of  the  Upper  Missouri  were 
depressed  and  covered  by  the  sea,  a  deep  channel  had  been  cut  by  some 
river  in  the  Lower  Silurian  and  Cambrian  strata  of  the  Minnesota  Valley ; 
but  the  small  width  of  this  channel  indicates  that  the  stream  then  flowing 
here,  probably  westward,  was  not  larger  than  the  present  Minnesota  River 
This  and  many  other  streams  of  similar  size,  flowing  into  the  Cretaceous 
ocean  as  it  spread  to  the  east  over  the  former  land  surface  of  Iowa,  Minne- 
sota, and  Manitoba,  contributed  part  of  the  detritus  which  made  its  vast 
mass  of  sediments,  probably  averaging  a  quarter  of  a  mile  in  depth  over 
most  of  its  area.  These  beds  could  be  supplied  only  by  extensive  and 
deep  denudation  upon  the  land  areas  both  west  and  east  of  the  Cretaceous 
mediterranean  sea. 

The  very  great  disturbances  of  the  region  on  the  west  in  the  elevation 
of  the  Cordilleran  Mountain  ranges,  since  the  Cretaceous  period,  make  it 
impossible  to  trace  there  the  course  of  the  larger  tributaries  to  this  sea. 
On  the  east  half  of  the  continent  the  principal  drainage  system,  carrying 
its  vast  freight  of  detritus  west  to  the  Cretaceous  ocean,  is  probably  marked 

'  Bulletins  of  the  Minnesota  Academy  of  Natural  Sciences,  Vol.  I,  p.  348.      Geology  of  Minne- 
sota, Final  Report,  Vols.  I  and  II. 


102  THE  GLACIAL  LAKE  AGASSIZ. 

by  the  chain  of  great  lakes  from  Ontario  to  Superior,  the  west  end  of  which 
is  close  to  the  east  border  of  the  submerged  belt.  At  that  time,  and 
onward  tln'ough  the  Tertiary  era,  much  of  this  eastern  land  area  appears 
to  have  been  elevated  at  least  several  hundred  feet  above  its  present  level, 
so  that  streams  eroded  the  deep  basins  which  are  now  occupied  by  these 
lakes,  but  then  had  a  continuous  westward  descent.  It  seems  probable 
also  that  other  great  tributaries  may  have  flowed  westward  and  southward 
into  the  Cretaceous  sea,  bringing  sediments  eroded  from  the  areas  of  Hud- 
son Bay,  Lake  Athabasca,  and  Great  Slave  and  Great  Bear  lakes.  The 
absence  of  Mesozoic  and  Tertiary  formations  on  the  east  border  of  the  con- 
tinent north  of  the  southern  coast  of  New  England  shows  that  from  the 
Gulf  of  Maine  to  Labrador  and  Hudson  Bay  the  land  during  these  eras 
stood  higher  above  the  sea-level  than  now.  So  long-continued  high  eleva- 
tion, probably  culminating  at  the  beginning  of  the  Glacial  period,  enabled 
streams  to  erode  the  fjords  of  Maine,  Newfoundland,  and  Labrador,  the 
gulf  and  estuary  of  the  St.  Lawrence,  the  deep  channel  of  the  Saguenay, 
and  the  broad  straits  and  bays  dividing  the  lands  of  the  Arctic  archipelago 
and  separating  them  from  Greenland. 

DENUDATION    OF    THE    CRETACEOUS    AREA. 

EROSION    OF    THE    PLAINS    TO    A    BASELEVEL. 

Rains,  rills  and  rivulets,  creeks  and  rivers  have  been  slowly  but  con- 
stantly wearing  away  the  Cretaceous  formations  since  their  elevation  above 
the  sea  and  the  drainage  of  the  immense  Laramie  lake,  which  for  a  long 
period  covered  much  of  their  area.  When  these  marine  and  lacustrine 
deposits  were  first  raised  to  be  diy  land,  they  had  a  monotonously  flat  sur- 
face; and  they  probably  extended  east,  as  we  have  seen,  over  the  entire 
basin  of  the  Red  River  of  the  North  and' of  the  great  lakes  of  Manitoba, 
from  which  they  now  reach  to  the  Rocky  Mountains.  The  greater  part  of 
the  present  Cretaceous  area,  though  eroded  far  below  its  original  surface, 
is  flat,  undulating,  or  only  moderately  rolling,  and  conetHutes  a  broad 
expanse  of  plains  with  very  slow  ascent  westward.  But  here  and  there 
isolated  areas  of  much  higher  hilly  land,  as  the  Turtle  Mountain,  consist  of 
remnants  of  horizontal  Cretaceous  strata  which  elsewhere  have  suff'ered 


DENUDATIOI^  OF  THE  WESTERN  PLAINS.  103 

clenudatioii  over  all  the  surrounding  country.  The  plains  have  been 
formed  by  the  erosion  of  this  vast  area  to  a  uniform  baselevel,  excepting 
only  the  isolated  hilly  tracts  of  comparatively. small  extent,  which  serve  to 
show  that  on  the  eastern  part  of  the  plains,  in  North  Dakota  and  south- 
western Manitoba,  a  thickness  of  not  less  than  500  to  1,000  feet  of  the 
Laramie,  Fox  Hills,  and  Fort  Pierre  formations  has  been  carried  away. 
Around  the  Highwood  and  Crazy  mountains,  in  central  Montana,  accord- 
ing to  Prof.  W.  M.  Davis^  and  Dr.  J.  E.  Wolff,"  the  corresponding  erosion 
of  the  plains  m  horizontally  bedded  Cretaceous  formations  has  been  3,000 
to  5,000  feet. 

When  the  depth  and  great  extent  of  this  denudation  are  compared  with 
those  of  the  subsequent  erosion  which  formed  the  Red  River  Valley  and 
the  lowland  adjoining  the  Manitoba  lakes  by  the  removal  of  the  foraier 
eastern  part  of  the  Cretaceous  plains  to  the  limit  of  the  great  escarpment 
west  of  Lake  Agassiz,  the  early  baseleveling  seems  probably  to  have 
occupied  the  Eocene  and  Miocene  periods,  with  nearly  all  of  the  Pliocene, 
comprising  nine-tenths  or  a  longer  portion  of  the  whole  Tertiary  era.  Its 
duration  apparently  coincided,  as  to  both  beginning  and  end,  with  the 
Tertiary  or  Somerville  cycle  of  partial  baseleveling  which  Davis  and 
Wood  have  studied  in  Pennsylvania  and  northern  New  Jersey  and  believe 
to  have  affected  a  large  area  of  the  other  Eastern  States.^  The  termination 
of  the  denudation  forming  the  plains  of  the  Cretaceous  area,  and  their  uplift 
to  undergo  the  erosion  of  the  Red  River  Valley  and  of  the  present  Assini- 
boine  and  Saskatchewan  valleys,  were  probably  also  contemporaneous  with 
the  great  epeirogenic*  movement  which  in  California,  according  to  Mr.  J.  S. 
Diller,  ended  a  long  cycle  of  baseleveling  that  had  extended  through  the 
whole  of  Cretaceous  and  Tertiary  time,  and  raised  a  part  of  that  base- 
leveled  district  at  the  beginning  of  the  Quaternary  era  to  form  the  lofty 

'  Mining  Industries  of  the  United  States,  Tenth  Census,  Vol.  XV,  pp.  710,  737,  745. 

-Notes  on  the  Petrography  of  the  Crazy  Mountains  and  other  localities  in  Montana  Territory, 
p.  16.     Bull.  Geol.  Soc.  Am.,  Vol.  Ill,  1892,  pp.  445-452. 

'National  Geographic  Magazine,  Vol.  1, 1889,  pp.  183-253;  Vol.  11,  1890,  pp.  81-110.  Proceedings, 
Boston  Society  of  Natural  History,  Vol.  XXIV,  1889,  pp.  365-423. 

■•A  term  proposed  by  Gilbert,  equis-alent  with  continent-making.  "The  process  of  monutain 
formation  is  orogeny ;  the  process  of  contiueut  formation  is  epeirogentj."  U.  S.  Geol.  Survey,  Monograph 
I,  Lake  Bonneville,  1890,  p.  340. 


104  THE  GLACIAL  LAKE  AGASSIZ. 

Sierra  Nevada/  Again,  the  same  record  of  long-continued  baseleveling, 
followed  by  uplift  and  a  new  cycle  of  rapid  valley  erosion,  is  found  by 
Powell  and  Dutton  in  the  plateaus  and  Grand  Canyon  of  the  Colorado.^ 
The  denudation  above  these  plateaus,  when  compared  with  the  studies  thus 
noted  in  other  regions  and  with  the  total  erosion  of  the  canyon,  seems  to 
have  required  not  only  the  Eocene  and  Miocene  periods  but  also  most  of 
the  Pliocene;  for  the  ratio  of  the  denudation  to  the  canyon-cutting  must 
be  nearly  or  quite  as  great  as  that  between  the  duration  of  the  entire 
Tertiary  era  and  the  comparatively  short  time  since  its  close.  Instead  of 
referring  the  division  of  these  parts  of  the  history  of  the  Grand  Canyon 
district  to  the  beginning  of  the  Pliocene,  as  was  done  provisionally  by 
Dutton,  it  may  therefore  mark  the  final  stage  of  the  Pliocene  and  the 
inauguration  of  the  Glacial  period,  with  high  elevation  of  all  the  northern 
part  of  this  continent  and  of  the  glaciated  northwestern  portion  of  Europe.^ 

LATER  EROSION  OF  THE  TROUGH  OF  LAKE  AGASSIZ. 

At  the  time  of  uplifting  of  the  plains  near  the  end  of  the  Pliocene 
period,  this  great  baseleveled  region  appears  to  have  stretched  from  the 
Rocky  Mountains  to  the  Archean  hills  on  the  eastern  border  of  Lake 
Agassiz,  and  to  have  included  also  the  expanse  of  flat  or  only  moderately 
undulating  country  which  slowly  falls  from  Lake  Winnipeg  and  the  upper 
part  of  the  Nelson  River  toward  Hudson  Bay.  The  Tertiary  drainage  of 
this  district,  from  the  present  sources  of  the  Saskatchewan,  Red,  and  Rainy 
rivers  to  Hudson  Bay  and  Strait,  probably  formed  a  gi-eat  river  flowing 
through  the  Apjialachian-Laurentide  mountain  belt  in  the  deep  valley 
which  is  now  submerged  to  form  this  strait,  and  emptying  into  the  Atlantic 
between  Labrador  and  Cape  Farewell.  The  depression  of  the  lower  part 
of  this  basin  beneath  the  sea  seems  to  me  referable  to  the  time  of  the  cul- 
mination and  departure  of  the  Quaternary  ice-sheet.      Between  the  Ter- 

'  U.  S.  Geol.  Survey,  Eighth  Annual  Report,  pp.  428-432.  Compare  also  articles  hy  Prof.  Joseph 
Le  Conte,  Am.  Jour.  Sci.  (3),  Vol.  XIX,  pp.  176-190,  March,  1880;  Vol.  XXXIl,  pp.  167-181,  Sept.,  1886; 
Vol.  XXXVIIl,  pp.  257-263,  Oct.,  1889. 

*  Exploration  of  the  Colorado  River  of  the  West,  1875.  Geology  of  the  eastern  portion  of  the 
Uinta  Mountains,  1876.  U.  S.  Geol.  Survey,  Monograph  ll,Tertiary  History  of  the  Grand  Cafion  District, 
1882.    Am.  Jour.  Sci.  (3),  Vol.  XXXII,  pp.  170,  171,  .Sept.,  1886. 

"Am.  Geologist,  Vol.  VI,  pp.  327-339,  396,  Dec,  1890.  Am.  Jour.  Sci.  (3),  Vol.  XLl,  pp.  33-52,  Jan., 
1891 ;  Vol.  XLVI,  pp.  114-121,  Aug.,  1893. 


EROSION  OF  THE  TROUGH  OF  LAKE  AGASSIZ.  105 

tiaiy  baseleveling  and  this  subsidence  a  widely  extended  epeirogenic  uplift 
of  North  America  intervened.  To  this  period  of  late  Pliocene  and  early 
Quaternary  elevation  belong  the  erosion  of  the  canyons  of  the  Colorado 
and  its  tributaries,  of  the  canyons  on  the  slopes  of  the  Sierra  Nevada,  and 
much  river  channeling  of  the  plains  east  of  the  Rocky  Mountains. 

The  eastern  margin  of  these  plains,  which  probabl)"  extended,  as  before 
noted,  over  the  whole  area  of  Lake  Agassiz,  was  then  subjected  to  renewed 
erosion,  removing  the  mostly  soft  Cretaceous  sti-ata  upon  a  width  of  a 
hundred  miles  or  more  and  to  a  depth  westward  of  several  hundred  feet. 
Previous  to  this  new  cycle  of  active  work  by  tlie  streams,  Riding  and 
Duck  mountains  stood  above  the  general  level,  like  Turtle  Mountain  and 
other  isolated  high  areas  farther  west;  and  the  maximum  depth  of  the  late 
stream-cutting  by  which  the  trough  of  the  Red  River  Valley  and  Lake 
Agassiz  was  formed  is  approximately  measured  by  the  height  of  the  Pem- 
bina Mountain  escarpment,  which  rises  300  to  400  feet  from  its  base  to  its 
crest  along  its  extent  of  about  80  miles.  The  greater  part  of  this  erosion 
we  must  attribute  to  the  probably  long  time  of  elevation  preceding,  and 
finally  at  its  climax  producing,  the  ice-sheet  of  the  Glacial  period.  So 
far  as  can  be  discerned,  the  entire  hydrographic  basin  of  Lake  Agassiz 
may  have  continued,  through  all  these  vicissitudes  of  changes  of  levels, 
excepting  when  it  was  wholly  or  partially  ice-covered,  to  be  drained  in 
the  same  north  and  northeast  direction  as  during  the  Tertiary  era  and  at 
the  present  day.^ 

In  the  progress  of  denudation  by  the  Tertiary  baseleveling  and  by 
the  later  erosion  of  the  hollow  which  was  to  hold  Lake  Agassiz,  some  of 
the  Cretaceous  strata  have  proved  more  durable  than  those  next  above 
and  below,  and  consequently  have  had  a  more  important  influence  on  the 
topography.  This  is  especially  noteworthy  in  the  case  of  the  Fort  Pieire 
formation,  which  forms  the  upper  and  main  part  of  the  great  escarpment 
that  borders  the  west  side  of  Lake  Agassiz  from  the  Coteau  des  Prairies 
north-northwest  to  the  Saskatchewan  River.  East  of  the  Red  River  Valley 
in  Minnesota  the  similar  but  less  prominent  ascending  slope  from  the  flat 

■  Am.  Geologist,  Vol.  XIV,  pp.  235-246,  Oct.,  1894.     Bulletin  Geol.  Soo.  of  America,  Vol.  VI,  pp.  17-20, 
•Nov.,  1894. 


106  THE  GLACIAL  LAKE  AGASSIZ. 

valley  plain  doubtless  also  consists  of  Cretaceous  shales,  perhaps  chiefly 
the  Niobrara  and  Fort  Bentou  formations,  beneath  the  envelope  of  glacial 
drift.  Farther  east  and  southeast,  through  northern  and  central  Minnesota, 
it  seems  certain  that  at  least  many  Cretaceous  knobs  and  hills  thus  far  had 
escaped  the  general  Tertiary  and  early  Pleistocene  denudation,  but  most  of 
them  were  leveled  during  the  Ice  age  and  mingled  with  the  glacial  drift. 
Westward  from  the  Pembina  and  Manitoba  escai-pment  the  Fort  Pien-e 
formation  generally  constituted  the  preglacial  surface,  and  is  now  the  floor 
on  which  the  drift  lies,  until  it  is  succeeded  by  the  Laramie  series.  This 
again  includes  especially  enduring  beds,  which  have  caused  the  preservation 
of  extensive  outlying  areas,  as  the  Turtle  Mountain  and  probably  other 
masses  of  hills  farther  north,  situated  many  miles  east  of  the  principal 
Laramie  outcrop.  In  the  same  way  that  the  Fort  Pierre  formation  makes 
the  escarpment  west  of  the  valley  of  the  Minnesota  and  Red  rivers  and  the 
Manitoba  lakes,  the  Laramie  beds,  underlying  the  drift,  make  the  greater 
part  of  the  equally  prolonged  terrace-like  highland  of  the  Coteau  du  Mis- 
souri from  South  Dakota  northwesterly^  through  North  Dakota,  Assiniboia, 
and  Saskatchewan.  Numerous  outliers  exist,  however,  east  of  the  main 
course  of  this  coteau,  in  the  region  crossed  by  the  North  Saskatchewan 
River. 

The  course  of  the  preglacial  rivers  flowing  from  the  Cretaceous  area 
west  of  Lake  Agassiz,  after  the  late  Pliocene  uplifting  of  the  continent, 
probably  coincided  approximately  with  the  present  avenues  of  di-ainage 
throughout  the  region  north  of  the  international  boundarj^,  in  the  Assini- 
boine,  Saskatchewan,  and  Athabasca  basins.  In  North  and  South  Dakota, 
the  present  channel  of  the  Missouri  River,  as  shown  by  Gen.  G.  K.  Warren^ 
and  by  Prof  J.  E.  Todd,  dates  only  from  the  Glacial  period,  this  great 
stream  having  been  turned  aside  by  the  ice-sheet  to  the  west  and  south 
from  its  preglacial  course,  which  may  have  occupied  the  valley  of  the 
James  or  Dakota  River,  nearly  parallel  with  the  Missouri  of  to-day,  or 
perhaps  continued  east  to  the  most  southern  bend  of  the  Souris  River,  or 
to  the  Sheyenne  and  Red  rivers.  Professor  Todd  finds  also  in  the  topog- 
raphy of  that  region  evidence  that  in  preglacial  time  the  great  tributaries 
coming  from  the  west  to  join  this  part  of  the  Missouri,  namely,  the  Cannon 

•Annual  Report  of  the  Chief  of  Engineers,  U.  S.  Army,  for  1868,  pp.  307-314. 


THE  PEEGLACIAL  CONTOUE.  1()7 

Ball  River,  the  Grand  and  Jloreau  rivers,  then  united,  the  Cheyenne,  and 
the  White  River,  flowed  east  to  the  James  Valley;  and  he  is  inclined  to 
believe  that  from  that  valley  the  great  stream  formed  by  these  affluents 
passed  northeast  to  the  Red  River  of  the  North  and  Hudson  Bay.^  That 
the  greater  part  of  the  excavation  of  the  trough  of  Lake  Agassiz  could  be 
accomplished  by  a  river  of  such  size  during  the  Lafayette  period  of  conti- 
nental elevation,  following  the  Pliocene  period  and  inaugurating  the  Ice 
age,  may  be  readily  believed  when  we  compare  it  with  the  Lafayette 
erosion  of  the  Mississippi,  which  from  Cairo  southward,  along  an  extent  of 
abc^ut  500  miles,  formed  a  channel  200  to  300  feet  deep  and  averaging  60 
miles  wide.^ 

Tertiary  and  early  Quaternary  erosion  had  sculptured  the  grand  features 
of  the  basin  of  Lake  Agassiz,  and  its  whole  extent  probably  had  approx- 
imately the  same  contour  immediately  before  the  accumulation  of  the  ice- 
sheet  as  at  the  present  time.  The  surface  of  the  feldspathic  Archean  rocks 
was  doubtless  in  many  places  decomposed  and  kaolinized  as  it  is  now  seen 
where  they  are  uncovered  in  the  Minnesota  Valley,  and  as  such  rocks  are 
frequently  changed  to  a  considerable  depth  in  regions  that  have  not  been 
glaciated.  On  these  and  all  the  other  rock  formations  the  ordinary  disinte- 
grating and  eroding  agencies  of  rain  and  frost  had  been  acting  through  long 
ages.  Much  of  the  loose  material  thus  supplied  had  been  carried  by  streams 
to  the  sea,  but  certainly  much  also  remained  and  was  spread  in  general 
with  considerable  evenness  over  the  surface,  collecting  to  the  greatest  depth 
in  valleys,  while  on  i-idges  or  hilltops  it  would  be  thin  or  entirely  washed 
away.  Except  where  it  had  been  transported  by  streams  and  consequently 
formed  stratified  deposits,  the  only  fragments  of  rock  held  in  this  mass 
would  be  from  underlying  or  adjoining  rocks.  The  surface  then  probably 
had  more  small  inequalities  than  now,  due  to  the  irregular  action  of  the 
processes  of  weathering  and  denudation,  which  are  apt  to  spare  here  and 
there  isolated  cliffs,  ridges,  and  hillocks;  but  most  of  these  minor  features 
of  the  topography  have  been  obliterated  by  glacial  erosion  or  buried  under 
the  thick  mantle  of  the  drift. 


'Proc,  A.  A.  A.  S.,  Vol.  XXXIII,  1884,  pp.  381-393,  with  map. 

2  Am.  Naturalist,  Vol.  XXVIII,  pp.  979-988,  Dec,  1894.     Bulletin,  Geol.  Soc.  of  America,  Vol.  V,  1894 
pp.  87-100.  ' 


CHAPTER  IV. 

THE    GLACIAL    PERIOD    AND    ITS    DRIFT    DEPOSITS. 

REVIEW   OF   THE   GLACIAL,  PERIOD  IN  NORTH  AMERICA. 

In  the  latest  geologic  period,  immediately  preceding  the  Recent  and 
present  period  in  which  we  live,  the  north  part  of  our  continent  was  deeply 
enveloped  in  snow  and  ice.  Every  year  the  snowfall  was  greater  than 
could  be  melted  away  in  summer,  and  its  depth  gradually  increased  till  its 
lower  portion  was  changed  to  compact  ice  by  the  pressure  of  its  weight. 
This  pressure  also  caused  the  vast  sheet  of  ice  to  move  slowly  outward 
from  the  region  of  its  greatest  thickness  toward  its  margin. 

Among  the  proofs  of  this  Glacial  period,  it  is  first  to  be  observed  that 
the  surface  of  the  bed-rocks  in  the  northern  drift-covered  portion  of  the 
United  States,  and  thence  north  to  Hudson  Bay  and  the  Arctic  Ocean,  bears 
fine  scratches  and  markings,  called  strise,  like  those  which  are  found 
beneath  the  glaciers  of  the  Alps.  Only  one  cause  is  known  which  can 
produce  markings  like  these,  and  this  is  the  rasping  of  stones  and  bowlders 
frozen  in  the  bottom  of  a  moving  mass  of  ice  accumulated  upon  the  land 
in  a  solid  sheet  of  great  extent  and  depth.  As  these  striae  are  found  upon 
the  rocky  surface  of  British  America  and  our  own  coantry  to  a  southern 
limit  that  coincides  approximately  with  the  course  of  the  Ohio  and  Missouri 
rivers,  we  must  conclude  that  an  ice-sheet  has  covered  these  regions. 

The  superficial  material  that  overlies  the  bed-rock  within  the  northern 
glaciated  area  has  everywhere  been  plowed  up  and  worked  over  hj  the 
slowly  moving  ice-sheet,  and  at  its  disappearance  the  greater  part  of  this 
glacial  drift  was  left  in  a  deposit  of  clay,  sand,  gravel,  and  bowlders, 
mixed  in  a  confused  mass,  which  is  called  till.  The  thickness  of  the  till 
upon  much  of  the  bed  of  Lake  Agassiz  is  from  50  to  200  feet,  but  in  some 
tracts  it  is  only  from  5  or  10  to  20  or  30  feet.     Throughout  nearly  all  of 

108 


EEVIEW  OF  THE  GLACIAL  PERIOD.  109 

this  lacustrine  area  lying  in  Minnesota  and  North  Dakota  it  forms  a  sheet 
of  such  great  extent  and  thickness  that  exposures  of  the  underlying  older 
rocks  are  very  rare  or  wholly  absent,  none  being  known  in  the  Minnesota 
portion  of  the  basin  of  the  Red  River. 

By  the  directions  in  which  the  bowlders  have  been  carried  from  their 
original  ledges,  and  by  the  courses  of  the  glacial  striae,  it  is  known  that 
in  the  northern  United  States  and  the  southern  part  of  the  Dominion  of 
Canada  the  ice  moved  in  general  from  north  to  south.  In  the  eastern 
provinces  and  in  New  England  its  current  was  prevailingly  southeastward, 
and  the  border  of  the  ice-sheet  was  pushed  into  the  Atlantic.  In  the 
region  of  the  Great  Lakes,  and  from  the  Laurentide  highlands,  James  Bay, 
and  the  south  half  of  Hudson  Bay  westward  nearly  to  the  Rocky  Moun- 
tains, the  ice-flow  was  mostly  to  the  southwest  and  south.  For  example, 
glacial  currents  moving  southwestward  spread  upon  eastern  Minnesota  a 
red  till,  thus  colored  by  the  hema,tite,  or  anhydrous  sesquioxide  of  iron, 
contained  in  its  portion  eroded  from  the  red  quartzite,  sandstone,  and  shales 
of  Lake  Superior;  but  in  western  Minnesota  the  ice  flowed  southward 
from  Lake  Winnipeg  to  Big  Stone  Lake  and  thence  southeast  into  northern 
Iowa,  spreading  a  blue  till,  with  many  limestone  bowlders  derived  from 
outcrops  of  Silurian  limestone  strata  near  Winnipeg. 

Besides  the  striae,  till,  and  transportation  of  bowlders,  another  proof 
that  the  drift  was  formed  by  vast  sheets  of  land  ice  is  supplied  by  terminal 
moraines,  or  hills,  knolls,  and  ridges  of  drift  heaped  along  the  ice  border. 
These  moraines  are  found  stretching  in  remarkably  curved  and  looped 
courses  across  the  Northern  States  from  Nantucket  and  Cape  Cod  to  Noi'th 
Dakota.  The  outermost  bounds  the  areas  that  were  overspread  by  the 
ice-sheet  during  the  late  part  of  the  Glacial  period,  which  Professor  Cham- 
berlin  has  named  its  East  Wisconsin  stage  ;^  and  others  mark  the  lines 
where  the  ice  border  paused  or  readvanced  during  its  subsequent  general 
recession. 

'"Preliminary  paper  on  the  terminal  moraine  of  the  Second  Glacial  Epoch,"  by  T.  C.  Cham- 
berlin,  in  the  Third  Annual  Report  of  the  U.  S.  Geol.  Survey,  pp.  291-402.  "Glacial  phenomena  of 
North  America,"  forming  two  chapters  in  J.  Geikie'a  The  Great  Ice  Age,  third  edition,  1894,  pp. 
724-775,  with  maps. 


110  THE  GLACIAL  LAKE  AGASSIZ. 


THE   CON'TINENTAT.   ICE-SHEET.' 


The  relation  of  Lake  Agassiz  to  the  ice-sheet  leads  us  to  inquire  more 
particularly  what  were  its  boundaries,  area,  and  thickness,  its  centers  of 
outflow,  the  manner  of  its  final  departure,  and  the  areas  probably  occupied 
by  its  latest  remnants. 

Boundaries. — The  extreme  southern  limit  of  the  glacial  drift  and  of  the 
ice-sheet  during-  its  gi'eatest  extent,  and  the  division  between  the  earlier 
drift,  belonging  to  the  Kansan  and  East  lowan  stages  of  the  Glacial 
period,  and  the  later  drift,  belonging  to  its  East  Wisconsin  stage,  during 
which  Lake  Agassiz  existed,  have  been  delineated  by  Professor  Cham- 
berlin,"  and  are  again  here  presented  in  PI.  XVI,  combining  the  results 
obtained  by  many  observers  during  the  past  twenty-five  years.  The 
southern  margin  of  the  drift  and  of  the  maximum  ice  extension  is  shown 
to  lie  wholly  within  the  United  States,  excepting  that  it  is  indented  at  the 
eastern  foot  of  the  Rocky  Mountain  range  by  an  angle  which  barely 
touches  the  forty -ninth  parallel.  Dr.  Dawson's  recent  map  of  the  extent 
of  the  drift  in  the  western  part  of  Canada,  however,  places  the  aj^ex  of  this 
angle  south  of  the  international  boundary,  along  which  he  has  had 
exceptional  opportunity  for  examination.^  But  the  limit  of  the  ice-sheet  in 
the  Wisconsin  stage,  or  the  time  of  formation  of  the  outermost  prominent 
moraines,  is  found  north  of  this  boundary  from  the  one  hundred  and  fourth 
to  the  one  hundred  and  fourteenth  meridian;  that  is,  across  southern 
Assiniboia  and  Alberta,  from  the  Coteau  du  Missouri  to  the  Rocky 
Mountains.  The  abundance  of  lakelets  held  in  hollows  of  the  drift  and 
the  small  amount  of  change  in  the  drift  contour  since  the  departure  of 
the  ice-sheet  indicate  that  during'  its  time  of  accumulation  of  marffinal 
moraines  in  these  pro%'inces  it  reached  south  to  the  Wood  Mountain  and 
Cypress  Hills  and  to  Lake  Pakowki  and  the  upper  portion  of  Milk  River. 

'The  greater  part  of  this  discussiou  of  the  extent  and  thickness  of  the  ice-sheet  is  from  the 
author's  previously  published  articles,  "Glacial  Lakes  iu  Canada,"  Bulletin,  G.  S.  A.,  Vol.  II,  1891,  jip. 
243-274;  and  "Glaciatiou  of  Mountains  in  New  England  and  New  York,"  Appalachia,  Vol.  V,  1889,  pp. 
291-312  (also  in  the  Am.  Geologist,  Vol.  IV,  Sept.  and  Oct.,  1889). 

=U.  S.  Geol.  Survey,  Seventh  Annual  Report,  PI.  VIII.  The  Great  Ice  Age,  third  edition,  1894, 
PI.  XV. 

'Trans.  Royal  Society  of  Canada,  Vol.  VIII.  sec.  4. 1890,  PI.  II. 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH    XXV.    PL.  XVI. 


57°    LoTT-gitude  37"  West  from  GreeiwvicK  ^ 


us  DiCN   »  CO   NY 


MAP  OF  THE  GLACIATED  AREA  OF  NOKTH  AMERICA 

Scale ,  abou-t  550  nailes  to  an  iucli . 


Areas  covered  b^Landlce  during  ti\eQiialcrji€iryEra  Quaternary  Lalte.s  13onr\eviUe  .uiill-nluniLan  ami  IhcCllHCial  L;ikcA^assiz 

Glacial  Currents  known  by  Striae 


a  ^ 


Glacial  Ciirreiils  known  b^HrLlt 'rrausportalioiiorollierwise  inl'orrod 


\  \  ^ 


Note. .- Th-^  dottfji-souOia-ii.  part  ofthe  drift  asrccu  in.  the- Missisaifipi  tutcL  Missouri  rCv&r  basins  reptvse.Ttt.s  tJit;  dnt't 
of  tihe.  ecbrlv  Kctnscui.  oJicl  Kasi  lowcin  sta^ca  ofgla'cintAxyn.  Thr.  norUimL  honndarv  of  Uii.t  tract  notes  Uifi 
ext&i-t  of  ijie  ie€-s?ieei  alfJie  Lime  of  beffifirting  of  lis  ninf^aiThe-foT-mJjiff  ni-JSastWCscoiisui  stfi^e- 


THE  CONTIiSrENTAL  ICE-SHEET.  HI 

Including  this  Canadian  part  of  the  southern  hmit  of  the  Wisconsin 
stage  of  the  ice-sheet,  its  course  at  the  beginning  of  its  time  of  formation 
of  the  series  of  marginal  moraines,  several  of  which  were  formed  contem- 
poraneously with  the  existence  of  Lake  Agassiz,  may  be  briefly  noted  as 
follows:  From  Nantucket,  Marthas  Vineyard,  Block  Island,  and  Long  Island 
it  I'uns  west-northwestward  across  northern  New  Jersey  and  northeastern 
Pennsylvania,  to  an  angle  near  Salamanca,  N.  Y.,  about  50  miles  south  of 
Buffalo  and  the  eastern  end  of  Lake  Erie;  thence  it  passes  southwestward 
into  southern  Ohio;  thence  west-northwestward  and  northward  in  numerous 
loops  through  Indiana,  northeastern  Illinois,  and  Wisconsin,  to  an  angle 
less  than  75  miles  southeast  of  the  western  end  of  Lake  Superior;  thence 
southward  to  Des  Moines,  Iowa;  thence  north-northwestward  to  the  head 
of  the  Coteau  des  Prairies;  again  southward  to  the  Missouri  River  and  the 
northeastern  edge  of  Nebraska;  thence  northwestward,  very  irregularly 
lobate,  througli  South  Dakota  and  North  Dakota,  to  Wood  Mountain,  in 
the  southern  edge  of  Assiniboia;  thence  westward  by  the  Cypress  Hills 
to  the  Rocky  Mountains  on  the  international  boundary;  and  thence,  in 
lobes  determined  by  the  mountainous  character  of  the  country,  across 
northwestern  Montana,  the  narrow  northern  extremity  of  Idaho,  and  the 
northeastern  edge  and  the  central  and  western  parts  of  Washington,  to 
the  Pacific  coast  on  the  latitude  of  48°,  Puget  Sound  and  the  Strait  of 
Juan  de  Fuca  being  wholly  inside  the  glaciated  area. 

Along  the  shores  of  British  Columbia  and  southern  Alaska  the  ice- 
sheet  pushed  through  gaps  of  the  Coast  Range  and  terminated  in  the  sea 
from  the  Strait  of  Juan  de  Fuca  and  Vancouver  Island  northwestward  to 
the  vicinity  of  the  Copper  River  and"  Prince  Williams  Sound.^  But  most 
of  Alaska  and  a  portion  of  the  adjacent  Northwest  Territory  of  Canada 
had  too  little  snowfall  or  were  otherwise  affected  by  climatic  conditions 
unfavorable  for  glaciation.  The  northwestern  limit  of  the  continental 
ice-sheet,  as   determined   by  Russell,^  McConnelV  and   Dawson,*  passes 

•G.  M.  Dawson,  in  Quart.  Jour.  Geol.  Soc,  London,  Vol.  XXXVII,  1881.  p.  278;  Trans.,  Roy.  Soc.  of 
Canada,  Vol.  VIII,  sec.  4, 1890,  PI.  II 

2 Bulletin,  G.  S.  A.,  Vol.  I,  pp.  140, 146-148. 

=  Ibid.,p.544. 

■iGeol.  and  Nat.  Hist.  Survey  of  Canada,  Annu.al  Report,  new  series.  Vol.  III.  for  1887-88,  pp.  132  B 
and  149  B. 


112  THE  GLACIAL  LAKE  AGASSIZ. 

northeastwardly  from  the  Coast  Ranges  about  Mount  St.  Elias,  to  cross 
the  Yukon  and  Pelly  near  the  meridian  136°  15',  and  thence  extends 
nearly  due  north  to  the  Arctic  Ocean,  close  west  of  the  mouth  of  the 
Mackenzie. 

The  scanty  observations  which  have  been  gathered  in  the  Arctic 
Archipelago  concerning  the  transportation  of  drift  from  the  Archean  area 
of  the  Northwest  Territory  northward  to  Baring  Land,  from  the  region  of 
the  Coppermine  River  northward  to  Prince  of  Wales  Strait,  from  North 
Somerset  100  miles  or  more  toward  the  northwest  and  northeast,  and  from 
south  to  north  in  Smith  Sound,  ^  indicate  that  the  greater  part  of  this 
archipelago  was  enveloped  by  the  continental  ice-sheet,  and  that  from 
Baffin  Land,*  North  Devon,  Ellesmere  Land,  and  Grinnell  Land  it  was 
continuous  eastward  to  the  ice-sheet  of  Greenland. 

On  the  Atlantic  coast  it  filled  Hudson  Strait  with  an  eastward 
outflow,  as  determined  by  Dr.  Robert  Bell;^  Labrador  was  wholly  ice- 
covered,  excepting  the  upper  portion  of  the  mountain  range  south  of  Cape 
Chidley,  which,  70  miles  from  the  cape,  attains  an  elevation  of  about 
6,000  feet  above  the  sea;''  Newfoundland,  enveloped  by  the  farthest  east- 
ward portion  of  this  ice-sheet,  was  glaciated  radially  outward  into  the 
ocean  on  the  north,  east,  and  south;*  and  thence  southwestward  the  border 
of  the  ice-sheet,  passing  beyond  the  shore-lines  of  Nova  Scotia,  New 
Brunswick,  and  Maine,  probably  reached,  at  its  time  of  maximum  area,  to 
the  irregular  submarine  ridges  and  plateaus  of  the  Fishing  Banks,  which 
consist  of  Tertiary  strata,  more  or  less  overspread  with  morainic  and 
iceberg  drift  deposits,  extending  from  Newfoundland  to  Cape  Cod  and 
Nantucket. 

Area  and  thickness. — The  part  of  North  America  and  outlying  islands 
which  were  covered  by  the  ice-sheet  and  are  now  overspread  with  its  drift 
amount  to  about  4,000,000  square  miles,  as  shown  on  PI.  XVI.      The 

'Gr.  M.  Dawson,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  Vol.  II,  for  1886, 
pp.  56-58  R. 

'Geol.  and  Xat.  Hist.  Survey  of  Canada,  Report  of  Progress,  1882-84,  p.  36  DD ;  Annual  Report, 
Vol.  IV,  for  1888-89,  p.  Ill  E. 

2 A.  .S.  Packard,  Memoirs  of  the  Boston  Society  of  Natural  History,  Vol.  1,  1866,  pp.  219,220;  The 
Labrador  Coast,  1891. 

"John  Milne,  Quart.  Jour.  Geol.  Soc,  London,  Vol.  XXX,  1874,  pp.  725-728. 


AEEA  AND  THICKNESS  OF  THE  ICESHEET.  113 

thickness  of  the  ice-sheet,  known  by  the  Uniits  of  glaciation  on  mountains, 
inci'eased  from  a  few  hundred  feet  in  the  vicinity  of  its  border  to  about  1 
mile  at  a  distance  of  200  to  250  miles  inside  the  border,  both  in  New- 
England  aiid  in  British  Columbia;  and  from  these  data  and  from  the 
courses  of  glacial  movement  and  distribution  of  the  drift,  it  is  computed  to 
have  ranged  from  1  to  2  miles  or  more — that  is,  from  5,000  to  10,000  or 
12,000  feet — in  its  central  portions.  Probably  two-thirds  of  a  mile,  or 
about  3,500  feet,  is  an  appi'oximate  estimate  of  the  average  thickness, 
or,  in  other  words,  mean  depth  of  the  ice-sheet  at  its  stage  of  maximum 
development.  Since  in  its  recession  the  ice  became  the  barrier  of  Lake 
Agassiz,  and  the  probable  influence  of  its  mass  in  producing  changes  in 
the  relative  levels  of  the  land  and  of  lakes  and  the  sea  will  therefore  be 
considered  in  a  later  part  of  this  report,  we  may  profitably  review  here  the 
evidences  that  it  attained  so  great  extent  and  depth. 

Measures  of  the  thickness  of  the  ice-sheet  and  of  the  rates  of  slope 
of  its  surface  in  New  England  and  New  York  are  supj^lied  by  its  drift  and 
strife  on  Mount  Katahdin,  the  White  Mountains,  the  Green  Mountains,  the 
Adirondacks,  and  the  Catskills. 

Prof.  C.  H.  Hitchcock,^  Prof  C.  E.  Hamlin,"  and  others  have  shown 
that  the  upper  limit  of  the  drift  on  Mount  Katahdin  is  about  4,700  feet 
above  the  sea.  The  top  of  this  mountain,  which  rises  500  feet  higher,  is 
covered  with  fragments  riven  from  the  underlying  rock  by  frost ;  but  it 
appears  to  be  destitute  of  drift,  and  probably  formed  an  island  projecting 
out  of  the  continental  mer  de  glace  during  the  stage  of  maximum  glacia- 
tion. If  we  compare  the  slope  of  the  surface  of  the  ice-sheet  with  the 
present  sea-level,  the  average  ascent  from  the  glacial  border  in  the  Atlantic 
to  Katahdin,  across  a  probable  distance  of  about  200  miles,  was  approxi- 
mately 25  feet  per  mile.  The  greatest  thickness  attained  by  the  ice  upon 
the  country  surrounding  the  base  of  Katalidin  was  about  4,000  feet,  or 
four-fifths  of  a  mile. 

The  most  noteworthy  observations  on  the  glaciation  of  the  White 
Mountains  are  those  of  Dr.  Edward  Hitchcock  in  1841,  marking  the  upper 

'Sixth  Anuual  Report  of  the  Secretary  of  the  Maine  Boartl  of  Agriculture,  1861. 
"Bulletin  of  the  Museum  of  Comparative  Zoology  at  Harvard  College,  Vol.  VII,  1881. 

MON  XXV 8 


1 14  THE  GLACIAL  LAKE  AGASSIZ. 

limit  of  the  usual  drift  deposits,  striae,  and  ice- worn  ledges  about  1,000  feet 
below  the  top  of  Mount  Washington ;  and  of  his  son,  Prof.  Charles  H. 
Hitchcock,  who  in  1875  found  glacially  transported  bowlders  on  the  very 
summit  of  this  mountain,  6,293  feet  above  the  sea.^  The  ice-sheet,  there- 
fore, at  one  time  overtopped  even  this  highest  peak  of  the  eastern  portion 
of  its  area.  Very  rare  bowlders  and  small  fragments  of  gneiss  foreign  to 
Mount  Washington,  which  in  its  upper  part  is  andalusite  mica,  schist  and 
gneiss,  occur  above  the  limit  of  the  ordinary  drift  action,  as  similar  foreign 
rock  fragments  are  found  very  scantily  on  the  high  portion  of  Katahdin  to 
within  600  or  500  feet  below  its  liighest  point.  But  on  Mount  Washington 
the  drift  fragments  are  scattered  thus  scantily  quite  to  its  summit,  near 
which  Professor  Hitchcock  has  obtained  two  bowlders,  each  weighing  about 
90  pounds.  One  of  these  is  in  the  museum  of  Dai'tmouth  College,  and  the 
other  in  that  of  the  Boston  Society  of  Natural  History.  These  bowlders 
were  transported  by  a  glacial  current  moving  from  northwest  to  southeast, 
and  in  the  distance  of  probably  15  miles  from  their  parent  ledges  to  the 
top  of  the  mountain  they  were  can'ied  upward  about  5,000  feet. 

Before  this  discovery,  while  it  was  believed  that  Mount  Washington 
and  adjacent  portions  of  the  same  range  rose  above  the  ice-sheet  at  its  time 
of  greatest  thickness.  Prof.  James  D.  Dana  had  computed,  fi-om  the  slope 
of  the  ice  surface  thus  known,  and  from  the  courses  of  striation  and  trans- 
portation of  bowlders  in  Canada,  that  the  elevation  of  the  surface  of  the 
ice-sheet  over  the  northern  border  of  New  England  was  about  8,000  feet, 
and  over  the  Canadian  watershed  between  the  St.  Lawrence  and  Hudson 
Bay  13,000  feet  above  the  present  sea-level,  giving  to  the  ice  an  average 
thickness  of  about  5,000  feet  in  the  region  of  the  White  Mountains,  6,500 
feet  on  the  international  boundary,  and  not  less  than  12,000  feet  on  the 
Laurentide  highlands.^  It  still  appears  to  be  true  that  the  upper  limit  of 
the  ice-sheet  was  about  1,000  feet  below  the  summit  of  Mount  Washington 
during  the  greater  part  of  the  Ice  age,  and  that  Dana's  estimates  of  the 
thickness  of  the  ice  farther  north  are  very  probable.  There  seem  to  be 
good  reasons  for  believing  that  the  land  at  length  sank  beneath  this  heavy 

'Geology  of  New  Hampshire,  Vol.  Ill,  1878. 

2Am.  Jour.  Sci.  (3),  Vol.  V,  pp.  198-211,  March,  1873, 


GLACIAL  DRIFT  ON  MOUNT  WASHINGTON.  115 

burden ;  and  to  that  time  I  would  refer  the  complete  glacial  envelopment  of 
Mount  Washington,  as  well  as  the  transportation  of  the  highest,  very  scanty 
di-ift  on  Katahdin.  This  depression  of  the  earth's  crust  led  to  changes  of 
climate,  from  the  rigorous  conditions  causing  glaciation  to  mild  temperatures 
by  which  the  ice  was  finally  melted ;  but  at  first  the  subsidence  was  perhaps 
attended  by  an  increase  in  the  thickness  of  the  ice,  whose  surface  may  have 
been  maintained  by  the  snowfall  during  a  short  time,  geologically  speaking, 
at  its  former  altitude,  while  the  area  of  the  White  Mountains  sank  the  1,000 
feet  which  would  envelop  the  top  of  Mount  Washington  in  the  ice-sheet. 
The  mountain  was  not  thus  ice-covered  so  long  that  the  glacial  cuiTent 
could  sweep  away  much  of  the  abundant  frost-i'iven  dtibris,  nor  conspicu- 
ously emboss  any  pi'ojecting  knobs  of  rock,  nor  bring  many  bowlders  .and 
fragments  of  foreign  drift.  In  the  220  miles  from  the  terminal  moraine  of 
Long  Island,  Marthas  Vineyard,  and  Nantucket,  north  to  Mount  Washing- 
ton, the  slope  of  the  ice  surface  therefore  averaged  in  its  maximum  about 
30  feet  per  mile,  compared  with  the  present  sea-level  and  height  of  the 
mountain,  but  was  only  about  25  feet  per  mile  through  the  greater  part  of 
the  Glacial  period.  It  is  presumable,  however,  that  in  a  process  of  subsid- 
ence of  the  land,  only  the  thickness  of  the  ice-sheet,  and  not  the  slope  of 
its  sm'face,  was  increased  when  the  mountain  became  wholly  ice-covered. 

Supplementing  the  reports  of  the  Geological  Survey  of  Vermont,  Mr. 
Edward  Hungerford  published  in  1868  a  valuable  paper  on  the  glaciation  of 
the  Green  Mountains,  ^  from  which  most  of  the  following  notes  are  derived, 
their  order  being  from  north  to  south.  Striae  on  the  summit  of  Jay  Peak, 
4,018  feet  above  the  sea,  bear  S.  40°  E.  Very  large  transported  bowlders 
occur  on  the  top  of  Mount  Mansfield,  with  strise  bearing  S.  23°  to  28°  E. 
This  mountain,  the  liighest  in  Vermont,  attains  the  elevation  of  4,430  feet. 
Masses  of  quartz  contained  in  the  mica-schist  of  the  top  of  Camels  Hump, 
4,088  feet  in  height,  show  fine  lines  of  striation,  noted  in  three  places,  S. 
10°  W.,  the  same  with  variation  to  due  south,  and  S.  35°  E.  It  is  also  to 
be  remarked  that  the  rounded  northwest  side  of  Camels  Hump  and  its 
jjrecipitous  cliff  on  the   south  and   southeast  afford    evidence   of  glacial 

'  Am.  Jour.  Sci.  (2),  Vol.  XLV,  pp.  1-5,  Jan.,  1868.     These  and  other  bearings  noted  in  this  volume 
are  referred  to  the  astronomic  meridian. 


116  THE  GLACIAL  LAKE  AGASSIZ. 

erosion.  Killington  Peak,  4,221  feet  high,  has  similar  rounded  outlines, 
forming  a  "well-defined  northern  stoss  side;"  and  Mr.  Hungerford  observed 
numerous  small  bowlders  of  foreign  rock  within  20  feet  of  the  highest  point. 
He  concludes  that  all  these  summits,  the  highest  in  Vermont,  were  enveloped 
by  the  ice-sheet. 

The  glacial  current  crossed  the  Green  Mountain  range  from  northwest 
to  southeast  and  south.  It  transported  bowlders  of  the  Burlington  red 
sandstone  across  the  range  near  Camels  Hump,  where  they  were  carried 
upward  3,000  feet  above  their  source,  and  deposited  them  in  the  Quechee 
Valley,  near  the  Connecticut  River,  and  in  Hanover,  N.  H.,  about  60  miles 
from  their  starting  point. 

The  Adirondack  group  culminates  in  Mount  Marcy  or  Tahawus,  5,344 
feet  above  the  sea;  and  Mount  Mclntyre,  at  5,113  feet,  is  next  in  elevation. 
Mr.  Verplanck  Colvin,  in  charge  of  the  Adirondack  Survey,  states  that  the 
summit  of  Marcy  is  contrasted  with  the  other  high  peaks  in  its  being  desti- 
tute of  glacial  drift;  but  its  embossed  and  rounded  ledges,  as  he  observes, 
indicate  glacial  erosion  there,  although  its  stride  have  been  obliterated  by 
weathering.^  This  summit  lies  about  125  miles  west  and  a  few  miles  south 
of  Mount  Washington,  and  its  distance  north  from  the  terminal  moraine  on 
Long  and  Staten  islands  is  about  235  miles.  The  average  slope  of  the  sur- 
face of  the  ice-sheet  from  its  terinination  to  the  Adirondack  Mountains  was, 
therefore,  not  less  than  23  feet  per  mile;  and  from  the  Catskills,  where  the 
upper  limit  of  glaciation  is  known,  it  was  not  less  than  17  feet  per  mile. 
How  much  it  may  have  exceeded  these  figures  can  not  be  determined,  but 
what  we  know  of  Katahdin  and  Washington  shows  that  the  peak  of  Marcy 
doubtless  lacked  only  a  little  of  rising  above  the  ice-sheet  at  its  time  of 
maximum  thickness.  In  this  connection  it  is  to  be  remarked  that  the 
change  from  a  northward  ascent  of  about  30  feet  per  mile  south  of 
the  Catskills  to  an  average  of  17  feet  per  mile,  or  shghtly  more,  for  the 
next  130  miles  to  the  Adirondacks  is  analogous  with  the  slopes  of  the 
Greenland  ice-sheet,  and  with  the  northward  ascent  of  the  ice -surface 
assumed  by  Dana  in  the  computation  before  mentioned,  namely,  an  aver- 

'  Seventh    Annual    Report    of    the  Topographical    Survey  of  the   Adirondack  Region,   to  the 
year  1879. 


THE  CATSKILL  MOUNTAINS.  117 

age  of  10  feet  per  mile  for  the  distance  from  the  international  boundary  to 
the  watershed  nortli  of  the  St.  Lawrence. 

In  New  Jersey  Prof  John  C.  Smock's  observations  show  that  the 
ice-sheet  covered  the  highest  point  of  the  State,  which  lies  near  its  most 
northern  angle,  at  an  elevation  of  1,804  feet.  Its  distance  north  from  the 
terminal  moraine  is  about  31  miles:  The  New  York  Highlands  and  the 
Shunemunk  and  Shawangunk  mountains  are  also  glaciated  to  their  crests. 
But  in  the  Catskill  Mountains  Professor  Smock  finds  that  the  glacial  drift 
and  strife  extend  upward  only  to  an  elevation  approximately  3,000  feet 
above  the  sea.^  Their  limit  is  thus  1,000  feet  below  the  highest  summits, 
Slide  Mountain,  the  culminating  point  of  this  group,  having,  according  to 
Guyot's  determination,  an  altitude  of  4,205  feet.  The  distance  from  Slide 
Mountain  south  to  the  terminal  moraine  on  Staten  Island  at  the  sea-level  is 
105  miles.  The  ice-sheet  in  this  distance  had  an  average  slope  of  nearly 
30  feet  per  mile,  or  slightly  less  than  a  third  of  a  degree;  and  a  consider- 
able area  of  the  Catskills  rose  above  its  surface  at  its  time  of  maximum 
thickness  and  extent. 

Farther  to  the  west  the  continental  giacier  stretched  in  a  vast  expanse, 
unbroken  by  any  projecting  mountain  or  highland,  to  the  basin  of  Lake 
Agassiz,  and,  excepting  a  single  group  of  hills  which  rose  above  it,  I  believe 
that  the  same  ice  expanse  continued  to  the  Rocky  Mountains,  whose  sum- 
mits, as  will  be  presently  shown,  appear  also  to  have  been  wholly  ice- 
enveloped  in  the  region  of  the  Peace  River  and  northward. 

The  upper  portions  of  the  Cypress  Hills,  in  southwestern  Assiniboia, 
of  the  Hand  Hills,  in  eastern  Alberta,  and  of  the  Three  Buttes  or  Sweet 
Grass  Hills,  in  the  north  edge  of  Montana,  rose  above  the  glaciation  which 
spread  drift  on  all  the  surrounding  country.  Mr.  R.  G.  McConnell  writes 
of  this  region  as  follows  : 

The  western  part  of  the  Cypress  Hills  is  entirely  uuglaciated,  and  must  have 
formed  an  island  in  glacial  times  projecting  about  •lOO  feet  above  the  surface,  as  no 
drift  or  other  mark  of  glacial  action  was  observed  within  that  distance  of  the  summit, 
and  as  this  part  has  a  height  of  about  4,800  feet  above  the  sea,  this  would  give  the 
surface  of  the  glacial  sea  or  glacier,  disregarding  Post  Tertiary  changes  in  elevation, 

1  Am.  Jour.  Sci.  (3),  Vol.  XXV,  pp.  339-350,  May,  1883. 


118  THE  GLACIAL  LAKE  AGASSIZ. 

a  height  of  4,400  feet  above  the  present  sea-level.  The  Hand  Hills  are  stated  by  Mr. 
Tyrrell  to  be  uuglaciated  above  a  height  of  3,400  feet,'  and  as  these  hills  are  situated 
N.  40°  W.  from  the  western  end  of  the  Cypress  Hills,  at  a  distance  of  about  150 
miles,  a  line  connecting  the  bases  of  the  driftless  parts  of  the  two  plateaus  would 
incline  toward  the  northwest  at  a  rale  of  6.7  feet  per  mile,  and  would  have  an  average 
elevation  above  the  present  surface  of  about  1,550  feet.  Drift  was  also  observed  by 
Dr.  G.  M.  Dawson  on  the  West  Butte  [of  the  Sweet  Grass  Hills]  at  an  elevation  of 
4,660  feet,  or  1,260  feet  above  the  level  at  which  it  disappears  in  the  Hand  Hills, 
which  are  in  nearly  the  same  meridian,  and  260  feet  above  the  same  point  in  the 
Cypress  Hills.  These  differences  in  level,  divided  by  the  difference  in  latitude  of 
the  several  elevations,  aft'ord  evidence  of  a  Post- Tertiary  depression  of  the  plains  to 
the  north  in  this  region,,  relatively  to  those  in  the  vicinity  of  the  forty-ninth  parallel, 
of  about  7.2  feet  per  mile.  The  glacial  sea  or  continental  glacier  is  also  shown,  by 
subtracting  the  elevations  given  above  from  the  present  level  of  the  surface,  to  have 
had  a  maximum  depth  in  the  plains  surrounding  the  Cypress  Hills  of  2,000  feet,  and 
to  have  averaged  about  1,500  feet.^ 

On  the  Rocky  Spring  plateau,  25  miles  west -southwest  from  the  West 
Butte,  the  upper  limit  of  the  drift  is  reported  by  Dr.  Dawson  to  have  an 
elevation  of  about  4,100  feet.  The  descending  slope  of  the  ice-sheet  thus 
indicated  for  this  distance  is  22  feet  per  mile. 

In  New  England,  as  before  noted,  we  are  indebted  to  Prof  C.  H. 
Hitchcock  for  the  proof  that  the  ice-sheet  enveloped  the  top  of  Mount 
Washington,  which  has  a  height  of  6,293  feet;  and  in  British  Columbia 
Dr.  George  M.  Dawson  finds  that  it  covered  mountains  5,000  to  7,640  feet 
high,  and  he  estimates  that  its  highest  central  part  upon  that  province  "had 
an  elevation  of  at  least  7,000  feet  above  the  mean  elevation  of  the  interior 
plateau,  which  would  be  equivalent  to  an  elevation  of  about  10,000  feet 
above  the  present  sea-level,  or  probably  11,000  feet  above  the  sea-level 
of  the  time."^  Between  these  eastern  and  western  areas  of  great  known 
thickness  of  the  ice,  as  determined  by  the  height  of  glacial  drift  and  strise 
on  mountains,  probably  the  ice-sheet  across  the  interior  of  Canada  at  one 
time  attained  a  thickness  of  a  mile  or  more  on  a  central  belt  several 


'  Mr.  Tyrrell,  in  the  later  Annual  Report  of  the  Canadian  Geol.  Survey,  Vol.  II,  for  1886, 
p.  145  E,  gives  thia  as  "  about  3,200  feet."    [W.  U.] 

=  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series.  Vol.  I,  for  1885,  pp.  75  and 
76  C.  Al.so  see  Dr.  George  M.  Dawson's  descriptions  of  the  superficial  deposits  and  glaciation  of  the 
Bow  and  Belly  rivers,  ibid.,  Report  of  Progress  for  1882-83-84,  pp.  139-152  C. 

^  Trans.,  Roy.  Soc.  Canada,  Vol.  VIII,  sec.  i,  p.  28. 


LAURENTIDE  AND  CORDILLERAN  GLAOIEKS.  119 

hundreds  of  miles  wide,  reaching  from  the  Rocky  Mountains  and  the 
Upper  Mackenzie  to  Reindeer  Lake  and  Lake  Winnipeg,  the  southwestern 
part  of  Hudson  Bay,  James  Bay,  the  Laurentide  highlands,  and  the 
southern  part  of  Labrador. 

This  proposition,  however,  differs  widely  from  the  opinions  of  Mr.  J.  B. 
Tyrrell,  who  thinks  that  a  narrow  unglaciated  tract  (designated  on  Pis.  II 
and  XVI  as  a  "debatable  tract")  borders  the  eastern  base  of  the  Rocky 
Mountain  range  in  Canada,^  and  of  Dr.  Dawson,  who  doubts  that  an  ice- 
sheet  has  ever  existed  on  a  much  wider  area  stretching  from  the  Rocky 
Mountains  far  eastward  across  the  Peace  and  Saskatchewan  plain  country 
nearly  to  Lake  Athabasca  and  the  lakes  of  Manitoba."  It  is  needful, 
therefore,  that  the  evidences  of  glaciation  in  that  district  should  be  defi- 
nitely and  particularly  stated.  Without  considering  here  the  methods  of 
formation  of  the  various  drift  deposits,  it  may  make  my  views  more  readily 
understood  to  add  that  I  agree  perfectly  with  Mr.  Tyrrell  in  referring  all 
deposits  of  bowlder-clay  or  till  directly  to  the  agency  of  land  ice,  without 
modification  or  aid  by  water;  while  Dr.  Dawson,  on  the  other  hand,  refers 
all  these  deposits  of  till  to  a  glacio-natant  origin — that  is,  to  deposition 
from  floating  ice  supplied  from  glaciers  and  borne  over  the  till-covered 
areas  during  their  submei'gence  by  lakes  or  the  sea. 

LAURENTIDE  AND  CORDILLEEAN  CENTERS  OF  OUTFLOW. 

The  prevailing  courses  of  glaciation  and  dispersal  of  the  drift  lead  me 
to  recognize,  with  Dr.  Dawson,  the  existence  of  two  central  areas  upon 
which  the  ice  was  accumulated  in  greater  depth  than  elsewhere,  and  from 
which  consequently  it  flowed  outward  on  all  sides.^     One  of  these  areas 

I  Bulletin,  G.  S.  A.,  Vol.  I,  pp.  396,  400,  401. 

"Trans.,  Roy.  Soc.  Canada,  Vol.  VIII,  sec.  4,  pp.  54-74. 

^  Dr.  George  M.  Dawsen,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol. 
II,  for  1886,  pp.  56-58  R;  Geol.  Magazine,  (3),  Vol.  V,  pp.  347-350,  Aug.,  1888;  Am.  Geologist,  Vol.  VI, 
pp.  153-162,  Sept.,  1890;  Transactions,  Royal  Society  of  Canada,  Vol.  VIII,  sec.  4.  1890,  pp.  3-74,  with 
five  majis. 

Compare  with  Dr.  Robert  Bell's  opinion,  based  on  his  observations  throughout  the  eastern  two- 
thirds  of  British  America,  that  during  the  Ice  age  "the  basin  of  Hudsons  Bay  may  have  formed  a 
sort  of  glacial  reservoir,  receiving  streams  of  ice  from  the  east,  north,  and  northwest,  and  giving  forth 
the  accumulated  result  as  broad  glaciers,  mainly  towards  the  south  and  southwest,'-'  and  also  to  the 
northeast  and  east  through  Hudson  Strait.  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress 
for  1882-83-84,  pp.  36,  37  DD. 

Also  see  an  article  by  Prof.  E.  W.  Clayjiole,  on  "Glaciers  and  glacial  radiants  in  the  Ice  age," 
Am.  Geologist,  Vol.  Ill,  pp.  73-94,  Feb.,  1889. 


120  THE  GLACIAL  LAKE  AGASSIZ. 

embraced  the  Laurentide  highlands,  James  Bay,  a  portion  of  Hudson  Bay, 
and  the  western  part  of  the  Archean  region  from  Lakes  Superior  and 
Winnipeg  to  Great  Slave  and  Great  Bear  lakes.  From  this  large  north- 
eastern or  Laurentide  center  of  outflow  the  ice-sheet  crept  southward, 
eastward,  and  northward  to  the  limits  of  glaciation  before  noted.  West- 
ward the  ice  from  this  area  outflowed,  as  I  beheve,  to  the  limit  of  Archean 
bowlders  on  or  near  the  base  of  the  Rocky  Mountains,  where  I  find,  from 
Dr.  Dawson's  observations  of  the  drift  in  Alberta  and  on  the  Peace  River, 
that  it  abutted  against  and  was  confluent  with  ice  outflowing  eastward  and 
southeastward  from  the  Rocky  Mountains.  The  other  area  whence  currents 
of  the  ice-sheet  flowed  radially  in  everj^  direction  was  the  northern  central 
part  of  British  Columbia;  and  the  portions  of  the  ice-sheet  pouring  outward 
respectively  from  these  two  centers  have  been  named  by  Dawson  the 
Laurentide  and  Cordilleran  glaciers.  Toward  the  south,  west,  and  north- 
west the  Cordilleran  outflow  extended  to  the  boundaries  of  our  glaciated 
area;  but  eastward,  pouring  through  passes  of  the  Rocky  Mountains,  and 
in  the  Peace  River  region  probably  overtopping  the  highest  summits,  which 
there  are  only  about  6,000  feet  above  the  sea,  the  Cordilleran  ice  pushed 
across  a  narrow  belt  adjoining  the  mountains  to  a  maximum  distance  of 
nearly  a  hundred  miles,  and  there  (on  land  about  2,500  feet  above  the  sea) 
became  confluent  with  the  Laurentide  ice,  the  two  united  currents  thence 
passing  in  part  to  the  south  and  in  part  to  the  north  from  the  interior  tract 
where  the  confluent  ice  was  thickest. 

JUNCTION    OF    THE    LAURENTIDE    AND    CORDILLERAN    DRIFT. 

Taking  up  the  particular  description  of  localities  where  the  junction 
of  the  Laurentide  and  Cordilleran  drift  has  been  observed,  we  may  begin 
at  the  international  boundary  and  proceed  northward.  Laurentian  erratics 
and  di-ift  are  stated  by  Dawson  to  extend  quite  to  the  foot  of  the  Rocky 
Mountains  near  the  forty-ninth  parallel,  and  to  occur  between  the  forty- 
ninth  and  fiftieth  parallels,  "stranded  on  the  surface  of  moraines  produced 
by  the  large  local  glaciers  of  the  Rocky  Mountains."^ 

In  Montana,  within  30  miles  southward  from  the  forty-ninth  parallel, 
Prof  G.  E.  Culver  finds  that  ice  was  accumulated  so  thickly  west  of  the 

1  Tran.s.,  Roy.  Soo.  Canada,  Vol.  VIII,  sec.  4,  p.  57 ;  Am.  Geologist,  Vol.  VI,  p.  162,  Sept.,  1890. 


JUNCTION  OF  LAUEENTIDB  AND  OOEDILLEEAN  DRIFT.        121 

main  eastern  range  of  the  Rocky  Mountains  that  it  outflowed  eastward 
thi'ough  the  passes,  carrying  diorite  bowlders  from  ledges  west  of  the 
watershed  to  a  distance  of  several  miles  on  the  plains  at  the  eastern  base 
of  the  mountains.  No  Laurentian  drift  was  observed  there,  but  in  the 
valley  at  the  head  of  St.  Marys  River,  a  tributary  of  the  Belly  River,  on 
longitude  113°  30',  5  to  20  miles  south  of  the  international  boundary, 
shore-lines  of  a  glacial  lake,  which  was  probably  formed  by  the  neighbor- 
ing barrier  of  the  Laurentide  ice-sheet  on  the  northeast,  occur  up  to  the 
height  of  at  least  800  feet  above  the  present  St.  Marys  lakes,  or  approx- 
imately 5,400  feet  above  the  sea.^ 

In  the  neighborhood  of  Calgary,  which  is  the  western  limit  of  Lau- 
rentian bowlders  and  till,  Dawson  reports  somewhat  farther  westward  a 
deposit  resembling  bowlder-clay,  in  which  the  stones  "are  entirely  those  of 
the  mountains  or  sandstone  blocks  from  the  underlying  beds."  Accord- 
ingly, he  declares  that  the  absence  of  Laurentian  erratics  west  of  Calgary 
is  probably  to  be  accounted  for  "by  the  existence  of  Rocky  Mountain 
glaciers  of  sufficient  size  in  this  region  to  fend  off  the  eastern  glaciating 
agent."  Again,  he  mentions,  west  of  Calgary,  "heavy  glacial  striation  in 
a  southward  or  southeastward  direction  *  *  *  about  13  miles  east  of 
the  mountains,  in  a  region  of  wide  vallej^s  and  low  foothills."" 

On  the  Peace  River,  in  its  course  close  east  of  the  Rocky  Mountains, 
and  on  its  tributary,  Piiie  River,  Dawson  reports  drift  containing  a  large 
proportion  of  "hard  quartzite  pebbles  like  the  more  resistant  materials  of 
the  axial  range  of  the  Rocky  Mountains.  These  are  mingled  Avith  a  pre- 
ponderating number  of  fragments  of  the  softer  sandstones  of  the  country, 
and  embedded  in  a  Avhitish  or  cream-colored  silty  clay,  not  unlike  the 
material  representing  the  bowlder-clay  over  wide  districts  west  of  the 
Rocky  Mountains.  No  Laurentian  or  other  fragments  of  eastern  origin 
were  observed  in  this  region."  Continuing  eastward,  these  drift  deposits 
become  more  conspicuous,  attaining  in  jjlfices  a  thickness  of  150  feet.  On 
reaching   the   D'Echafaud    River,    about   100   miles  from  the  mountains, 

'"Notes  on  a  littlo-kuown  region  in  northwestern  Montana,"  Transactions,  Wisconsin  Academy 
of  Science,  Arts,  and  Letters,  Vol.  VIII,  pp.  187-205,  with  map,  Dec  30, 1891. 

'Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress,  1882-84.  pp.  146  C,  151  C;  Annual 
Report,  new  series.  Vol.  I,  for  1885,  p.  167  B. 


122  THE  GLACIAL  LAKE  AGAiSSIZ. 

though  "no  change  in  the  character  of  the  drift  deposits  was  noted, 
*  *  *  Laurentian  pebbles  and  bowlders  were  for  the  first  time  seen 
in  considei'able  abundance.  *  *  *  East  of  this  point  *  *  *  the 
surface  is  thickly  covered  with  drift  deposits,  so  much  so  that  exposures 
of  the  underlying-  rocks  are,  as  a  rule,  only  found  in  the  larger  river 
valleys."^  No  better  evidence  could  be  desired  by  a  glacialist,  account- 
ing for  the  formation  of  the  bowlder-clay  by  the  agency  of  land  ice,  to 
demonstrate  the  confluence  here  of  two  currents  of  the  ice,  one  flowing 
eastward  from  the  Cordilleran  area  and  the  other  flowing  westward  from 
the  Archean  area,  whose  nearest  portion  is  on  Lake  Athabasca,  about  400 
miles  distant. 

Near  the  divide  between  the  Liard  and  Yukon  River  systems,  Dawson 
found  drift  on  the  summit  of  an  isolated  mountain  4,300  feet  above  the  sea 
and  about  1,000  feet  above  this  part  of  the  Pacific-Arctic  watershed.^  This, 
however,  is  on  the  west  side  of  the  Rocky  Mountains  proper,  which,  as 
defined  by  Dawson,  constitute  the  northeastern  marginal  range  of  the  broad 
mountainous  Cordilleran  belt.  With  this  definition,  the  Rocky  Mountains 
are  intersected  by  the  Mackenzie  River  south  and  west  of  Great  Bear  Lake. 

Farther  northward  the  Laurentide  or  eastern  portion  of  the  ice-sheet 
pushed  northwestward  to  the  extreme  limit  of  the  drift.  "The  till  near  the 
lower  ramparts  of  the  Mackenzie,"  according  to  Mr.  R.  G.  McConnell,  "is 
in  approximately  the  same  latitude  as  the  northern  boundary  of  the  Archean 
area  on  the  east,  and  the  gneissic  bowlders  which  it  contains  must  have 
traveled  either  directly  west  or  northwest  in  order  to  reach  their  present 
situation."  He  therefore  infers  that  "the  ice  from  the  Archean  gathering 
grounds  to  the  east  poured  westward  through  the  gaps  and  passes  in  the 
eastern  flanking  ranges  of  the  Rocky  Mountains  until  it  reached  the  barrier 
formed  by  the  main  axial  range,  when,  being  unable  to  pass  this,  it  was 
deflected  northwestward  in  a  stream  from  1,500  to  2,000  feet  deep  down  the 
valley  of  the  Mackenzie  and  thence  out  to  sea."^ 

All  the  testimony  thus  gathered  concerning  the  line  of  junction  and 
the  limits  of  the  eastern  and  western  drift  seems  to  the  present  writer  to 

>  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress,  1879-80,  pi5. 139, 140  B. 
■^  Ibid.,  Annual  Report,  Vol.  Ill,  for  1887-88,  p.  119  B. 
3  Bulletin,  G.  S.  A.,  Vol.  I,  p.  .543. 


COMPARISON  WITH  THE  GEEEJ^LAND  ICE-SHEET.  123 

amount  to  full  and  convincing'  proof  that  the  ice  of  the  Laurentide  and 
Cordilleran  areas  of  outflow  became  confluent,  and  at  its  culmination 
stretched  as  one  continuous  ice-sheet  from  the  Atlantic  to  the  Pacific, 
enveloping  the  northern  portion  of  the  Rocky  Mountains  in  their  compara- 
tively low  development  within  the  basin  of  the  Mackenzie  and  Peace 
rivers,  and  overspreading  the  whole  of  the  Dominion  of  Canada  south- 
ward, except  the  highest  parts  of  the  Rocky,  Selkirk,  and  Coast' ranges. 

COMPARISON    WITH    THE    PRESENT    ICE-SHEET    OF    GREENLAND. 

An  ice-sheet  similar  to  that  of  North  America  in  the  Glacial  pei'iod 
now  covers  the  Antarctic  lands,  and  another  is  spread  over  the  interior  of 
Greenland.  The  latter  has  been  so  far  explored  within  the  past  ten  years 
by  Nordenskjold,  Peary,  and  Nansen  as  to  give  us  a  knowledge  of  its 
slopes  and  the  altitude  of  its  surface,  with  which  the  ancient  ice-sheets  of 
North  America  and  Europe  may  be  most  instructively  compared. 

The  first  long  journey  on  the  Greenland  ice-sheet  was  accomplished 
by  Nordenskjold  in  1883,  going  eastward  from  Aulatsivik  Fjord,  close  south 
of  Disco  Bay,  near  latitude  68°  20'  north.  At  a  distance  of  about  73 
miles  from  the  head  of  this  fjord  and  edge  of  the  inland  ice  Nordenskjold 
reached  an  altitude  of  4,950  feet;  and  at  a  probable  distance  of  45  or  50 
miles  farther,  crossed  by  Lapps  on  the  peculiar  snowshoes  called  "ski,"  the 
barometers  indicated  a  height  of  6,386  feet.  The  average  ascent  of  the  ice 
surface  here  in  the  first  73  miles,  including  the  more  rapid  rise  near  the 
margin,  is  about  68  feet  per  mile,  or  slightly  less  than  three-quarters  of  a 
degree;  but  in  the  next  45  miles  of  estimated  distance  it  is  reduced  to  32 
feet  per  mile,  or  about  a  third  of  a  degree.^ 

A  second  important  journey  on  the  inland  ice  of  Greenland  was  by 
Lieut.  R.  E.  Peary  and  Christian  Maigaard  in  1886,  going  east  from  the 
head  of  Pakitsok  Fjord,  on  the  northeast  part  of  Disco  Bay,  in  latitude 
69°  30'  north.  These  explorers  advanced  to  an  estimated  distance  of 
about  100  miles  from  the  edge  of  the  ice,  attaining  an  altitude  of  about 
7,500  feet.2 

'  Science,  Vol.  II,  pp.  732-738,  with  map,  Dec.  7, 1883.  For  the  more  accurate  final  computations 
and  estimates  of  distance.'!  aud  altitudes,  see  The  First  Crossing  of  Greenland,  by  F.  Nansen,  1890,  Vol. 
I,  pp.  494-499,  with  map ;  Vol.  II,  pp.  467,  468. 

•  Bulletin  of  the  American  Geographical  Society,  Vol.  XIX,  1887,  pp.  261-289. 


124  THE  GLACIAL  LAKE  AGASSIZ. 

Two  years  later,  in  1888,  Dr.  Fridtjof  Nanseu  crossed  this  ice-sheet 
from  east  to  west  between  latitude  64°  10'  and  64°  45'  north.  The  width 
of  the  ice  here  is  about  275  miles,  extending  into  the  ocean  on  the  east, 
but  terminating  on  the  west  about  14  miles  from  the  head  of  Ameralik 
Fjord  and  70  miles  from  the  outer  coast-line.  For  the  first  15  miles  in  the 
ascent  from  the  east,  rising  to  the  altitude  of  1,000  meters,  or  3,280  feet, 
the  average  gradient  was  nearly  220  feet  per  mile.  In  the  next  35  miles 
an  altitude  of  2,000  meters,  or  6,560  feet,  was  reached;  and  the  average 
gradient  in  this  distance,  between  15  and  50  miles  from  the  margin  of  the 
ice,  was  thus  about  94  feet  per  mile,  or  a  slope  very  slightly  exceeding  1 
degree.  The  highest  part  of  the  ice-sheet,  about  112  miles  from  the  point 
of  starting,  was  found  to  have  an  altitude  of  2,718  meters,  or  about  8,920 
feet.  Its  ascending  slope,  tlierefore,  in  the  distance  from  50  to  112  miles 
was  about  38  feet  per  mile.  Thence  descending  westward,  the  gradients 
are  less  steep,  averaging  about  25  feet  per  mile  for  nearly  100  miles  to  the 
altitude  of  2,000  meters,  about  63  feet  per  mile  for  the  next  52  miles  of 
distance  and  1,000  meters  of  descent,  and  about  125  feet  per  mile  for  the 
lower  western  border  of  the  ice.^ 

Lieutenant  Peary,  in  an  expedition  from  Inglefield  Gulf,  near  latitude 
78°,  on  the  northwest  coast  of  Grreenland,  starting  early  in  May  and 
returning  August  6,  1892,  crossed  the  northwestern  and  northern  parts  of 
this  ice-sheet,  reaching  altitudes  of  5,000  to  8,000  feet,  and  determining 
approximately  the  northern  boundary  of  the  ice  from  Petermann  Fjord  to 
the  eastern  coast  at  Independence  Bay,  in  latitude  81°  37'  and  longitude 
34°  west  from  Greenwich. 

In  comparing  the  slopes  and  altitudes  of  the  upper  limits  of  glaciation 
on  mountains  in  Maine,  New  Hampshire,  and  New  Yoi'k,  with  the«ice  in 
Greenland,  we  observe  tlie  remarkable  contrast  that  the  former  show 
gradients  only  about  half  as  steep  as  the  latter.  Mount  Washington,  as 
before  noted,  indicates  an  average  gradient  of  only  about  25  feet  per  mile 
for  the  rise  of  the  ice  surface  along  a  distance  of  220  miles  from  its  margin 
during-  the  principal  part  of  the  Glacial  period;  to  Mount  Katahdin  in 
a  similar  distance  it  appears  to  have  risen  somewhat  less  steeply,  or  per- 

'  The  First  Crossing  of  Greenland,  Vol.  II,  pp.  464-466,  with  section  and  maps. 


GLACIATED  AREAS  UPLIFTED  AS  PLATEAUS.        125 

haps  nearly  the  same;  and  to  the  Catskills  the  apjiarent  ascent  was  only 
30  feet  per  mile  for  the  distance  of  100  miles  from  the  ice  border.  But  in 
Greenland  all  of  the  four  journeys  on  the  inland  ice  find  it  to  ascend 
with  much  steeper  slopes,  attaining  the  altitude  of  the  summit  of  Mount 
Washington  at  distances  which  vary  from  50  to  125  miles  from  its  edge. 
Nor  does  the  less  area  of  the  Grreenland  ice  explain  its  steeper  gradients, 
for  it  probably  has  a  length  of  more  than  20  degrees  from  south  to  north, 
or  over  1,400  miles,  with  a  width  of  200  to  600  miles,  and  an  area  of 
about  600,000  square  miles,  or  one-seventh  as  much  as  the  later  ice-sheet 
of  North  America. 

Apparently  the  c(jiiditions  for  outflow  of  the  ice  from  this  area  are 
similar  and  equally  favorable  with  those  which  prevailed  on  our  continent 
in  the  Glacial  period.  The  comparison  therefore  suggests  that  the  present 
elevation  of  the  glaciated  portion  of  this  continent  is  probably  much 
changed  from  that  which  it  had  during  its  epochs  of  glaciation.  If  the 
North  American  ice-sheet  during  its  stages  of  growth  and  culmination 
attained  steep  slopes  and  high  altitudes  near  its  borders  comparable 
with  the  Greenland  ice,  the  records  of  glaciation  on  our  mountains  show 
that  during  the  time  of  accumulation  of  the  ice  and  until  it  attained  its 
maximum  extent  the  glaciated  area  was  uplifted  as  a  high  continental 
plateau,  with  the  same  principal  topographic  features  of  mountains, 
valleys,  and  general  contour  as  in  preglacial  and  postglacial  times,  but 
having  in  its  outer  100  or  200  miles  slopes  of  probably  20  to  30  feet 
per  mile,  descending  from  the  jDlateau  of  the  interior  of  the  ice-enveloped 
country  to  its  margin.^ 

Similar  uplifting  seems  also  to  have  affected  the  glaciated  northwestern 
portion  of  Europe,  for  there,  too,  the  slopes  and  height  of  the  limits  of  the 
drift  resemble  those  of  North  America  rather  than  the  Greenland  ice-sheet. 
Prof.  James  Geikie  finds  that  the  surface  of  the  ice  which  moved  westward 
from  northern  Scotland  across  the  Minch  and  the  Hebrides  had  a  descent 
of  25  feet  per  mile;  "but  slight  as  that  incline  was,"  he  remarks,  "it  was 
probably  twice  as  great  as  the  slope  of  the  mer  de  glace  that  filled  up  the 
German  Ocean." ^     Mr.  T.  F.  Jamieson  therefore  concludes  that  when  the 

'  The  Ice  Age  in  North  America,  p.  595. 

=  Quart.  Jour.  Geol.  Sou.,  Vol.  XXXIV,  p.  G81,  Nov.,  1868. 


126  THE  GLACIAL  LAKE  AGASSIZ. 

ice-sheets  of  Scandinavia  and  Scotland  were  being  accumulated  tliese  coun- 
tries stood  far  above  their  present  height,  the  maximum  uplift  being  at  least 
equal  to  4,080  feet,  which  is  the  depth  of  Sogne  Fjord,  the  longest  and 
deepest  fjord  of  Norway.^ 

At  the  end  of  the  Glacial  period,  however,  the  glaciated  regions  are 
known  to  have  been  mostly  depressed  somewhat  below  their  present  level. 
This  change  seems  to  be  well  accounted  for  by  the  vast  weight  of  the  ice- 
sheet  itself,  causing  the  land  to  sink  finally  beneath  its  load;  and  the 
subsequent  rise  of  the  land  is  an  expression  of  the  buoyancy  of  the  earth's 
cnist  when  it  had  been  relieved  by  the  disappearance  of  the  ice.  The  pre- 
glacial  elevation  may  well  have  produced  a  cool  climate  throughout  the 
year,  with  abundant  snowfall  and  resulting  ice  accumulation;  and  the  sub- 
sidence of  the  burdened  land  would  cause  rapid  melting  of  the  ice  upon  its 
borders  and  thence  backward  progressively  over  its  whole  area. 

EECESSIOIS^  OF    THE    ICE-SHEET. 

During  the  departure  of  the  ice  its  melting  was  due  to  the  inflvience 
of  sunshine  and  rains,  the  latter  being  doubtless  brought  then,  as  now,  by 
great  storms  sweeping  across  the  continent  in  an  eastward  and  northeast- 
ward course.  In  consequence,  the  borders  of  the  ice-sheet  appear  to  have 
been  pushed  back  generally  in  the  same  northeastward  direction,  beginning 
on  the  west  in  the  region  of  the  Missouri  and  upper  Mississippi  rivers  and 
of  the  Red  River  of  the  North,  and  yielding  successively  or  almost  con- 
temporaneously the  region  of  the  Laurentian  lakes.  New  England,  and  the 
eastern  provinces  of  Canada."  Thus  Lake  Agassiz  was  formed  in  the  Red 
River  Valley,  and  the  basins  of  the  Lam-entiau  lakes  became  filled  by 
glacial  lakes  outflowing  southwestward  to  the  Mississippi,  until  the  outlet 
from  Lake  Ontario  by  the  Mohawk  and  Hudson  rivers  was  uncovered  from 
the  ice.  Along  the  valley  of  the  St.  Lawrence  the  glacial  current,  which 
had  before  passed  southeast  transversely  across  it  to  the  coast  of  New 
England,  was,  during  this  recession  of  the  border  of  the  ice-sheet,  deflected 
toward  the  southwest,  conforming  to  the  law  that  the  glacial  motion  near 
the  edge  of  the  ice  turned  perpendicularly  toward  its  boundary. 

'Geol.  Magazine  (3),  Vol.  VIII,  i>p.  387-392,  Sept.,  1891. 

2  Compare  Proc,  A.  A.  A.  S.,  Vol.  XXXII,  1883,  pp.  231-231 ;  and  Geology  of  Minnesota,  Vol.  I,  p.  611. 


RECESSION  OF  THE  ICE-SHEET.  127 

Extensive  and  thick  beds  of  gravel,  sand,  and  clay  or  fine  silt,  called 
stratified  or  modified  drift,  were  deposited  along  the  avenues  of  drainage 
from  the  glacial  boundary,  especially  during  its  rapid  final  recession.  The 
dissolution  of  the  ice,  with  accompanying  rains,  produced  extraordinary 
floods  along  all  the  rivers  flowing  away  from  the  waning  ice-sheet;  and 
these  were  heavily  laden  with  detritus  set  free  from  the  lower  part  of  the 
ice  in  which  it  had  been  held,  and  brought  down  by  the  rills  and  small  and 
large  streams  formed  on  the  melting  ice  surface.  Other  portions  of  the 
englacial  drift  were  let  down  as  an  upper  deposit  of  till,  which  lies  in  a 
loose,  unstratified  mass  upon  the  subglacial  till  or  ground  moraine.  The 
abundant  deposition  of  drift,  both  stratified  and  unstratified,  during  the 
final  melting  of  the  ice-sheet,  was  first  brought  into  due  prominence  by 
Prof  James  D.  Dana,^  who  denominated  this  the  Champlain  epoch,  deriv- 
ing the  name  from  its  marine  beds  adjoining  Lake  Champlain. 

On  the  Atlantic  Coast  the  Champlain  subsidence  of  the  land  below  its 
present  level  is  known,  from  fossihferous  marine  beds  overlying  the  till,  to 
have  been  slight  in  northeastern  Massachusetts,  150  to  230  feet  in  New 
Hampshire  and  Maine,  nothing  or  of  small  amount  in  Nova  Scotia,  but 
considerable,  with  increase  from  east  to  west,  along  the  lower  St.  Lawrence 
Valley,  being  375  feet  opposite  the  Saguenay  and  560  feet  at  Montreal, 
but  thence  diminishing  southward  along  Lake  Champlain  and  westward  in 
the  upper  St.  Lawrence  and  Ottawa  valleys.  The  country  southwest  of 
Hudson  Bay  sank  300  to  500  feet;  Labrador,  1,000  to  1,500  feet;  and 
western  Greenland  and  Grinnell  Land,  1,000  to  2,000  feet.  Again,  in 
British  Columbia  and  the  Queen  Charlotte  Islands  Dr.  Dawson  and  otliers 
find  proofs  of  submergence,  ranging  up  to  200  or  300  feet,  while  the  glacial 
conditions  still  endured. 

This  closing  stage  of  the  Glacial  period  was  immediately  succeeded 
by  a  time  of  great  erosion  of  the  valley  deposits  of  stratified  drift,  as  soon 
as  the  continued  glacial  recession  beyond  the  drainage  areas  of  the  rivers 
cut  off  the  supply  of  water  and  of  drift  that  had  been  derived  from  the 
melting  ice.  The  resulting  excavation  of  the  glacial  flood-plains  has  left 
remnants  of  those  deposits  in  conspicuous  terraces  along  all  our  river  val- 

'  Am.  Jour.  Sci.  (3),  A'ol.  V,  p.  198,  aud  various  papers  in  Vol.  X- 


128  THE  GLACIAL  LAKE  AGASSIZ. 

leys  which  lead  southward  within  the  glaciated  region  or  on  its  southern 
border;  and  postglacial  time,  extending  to  the  present  day,  is  therefore 
named  by  Dana  the  Recent  or  Terrace  epoch.  It  is  to  be  remarked,  how- 
ever, that  much  of  the  terracing  of  the  valley  di-ift  was  doubtless  done 
speedily  after  the  retreat  of  the  ice  from  any  basin,  while  yet  adjacent 
di-ainage  areas  on  the  north  were  receiving  from  it  thick  flood-plain  depos- 
its. The  Glacial,  Champlain,  and  Terrace  epochs  thus  overlap,  the  second 
being  wholly  and  the  third  partially  included  within  the  Glacial  or  Pleis- 
tocene period,  if  continental  areas  are  considered;  but  for  any  limited 
disti-ict,  as  a  single  river  basin,  the  sculpturing  of  the  terraces  took  place 
chiefly  after  the  departure  of  the  ice  beyond  its  watershed. 

Latest  glaciation  far  north. — In  the  latest  stages  of  the  glacial  recession 
the  ice-sheet  probably  became  divided  into  three  remnants,  one  covering 
northern  British  Columbia  and  contiguous  portions  of  the  Northwest  Terri- 
tory and  Alaska,  another  occupying  the  region  west,  northwest,  and  north 
of  Hudson  Bay,  stretching  northward  to  the  large  islands  of  the  Arctic 
Ocean,  and  a  third  covering  Labrador  and  the  country  north  of  the  St. 
Lawrence.  The  present  glaciers  of  British  Columbia  and  southern  Alaska, 
the  broad  Malaspina  glacier  or  ice-sheet,  described  by  Russell,  between  the 
St.  Elias  Range  and  the  ocean,  and  the  extensive  ice-enveloped  country 
seen  by  Russell  in  the  view  northward  from  Mount  St.  Elias,  estimated  by 
him  to  embrace  not  less  than  30,000  square  miles,  are  surviving  repre- 
sentatives of  glaciation  wliich  probably  has  been  continuous  in  that  region 
since  the  time  of  maximum  extent  and  depth  of  the  continental  ice-sheet.^ 
From  the  second  of  these  areas  glacial  cun-ents  moved  south-southwest- 
wardly  across  the  Churchill  River  and  Reindeer  and  Athabasca  lakes, 
partly  obliterating  the  earlier  westward  stria?,  and  southeastwardly  across 
Marble  Island,, in  the  northwestern  part  of  Hudson  Bay.  This  division  of 
the  North  American  ice-sheet  is  probably  still  represented  by  glaciers  or  a 
small  ice-sheet  in  Baffin  Land,  on  the  coast  of  Fox  Channel,  from  which 
its  icebergs  are  carried  southeastward  mto  Hudson  Strait.^     Possibly  the 

1  National  Geographic  Magazine,  Vol.  Ill,  pp.  53-203,  -with  19  plates.  May  29,  1891.    Am.  Jour. 
Sci.  (3),  Vol.  XLIII,  pp.  169-182,  with  map,  March.  1892.     Am.  Geologist,  Vol.  IX,  pp.  322-336,  May,  1892. 

2  Dr.   Robert  Bell,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1882-83-84, 
p.  24  DD. 


GLACIAL  CURRENTS  SHOWN  BY  STRI.E.  129 

recession  and  final  melting  of  the  continental  ice-sheet  caused  it  to  extend 
over  lands  within  the  Arctic  Circle  which  had  not  been  covered  by  the  ice 
when  it  reached  farthest  south.  From  the  melting  of  its  last  reriinants 
moisture-laden  winds  doubtless  have  carried  portions  of  it  across  Baffin 
Bay  and  Davis  Strait  to  be  deposited  again  in  the  ice-sheet  that  still  covers 
the  interior  of  Greenland. 

GLACIAIi   CURRENTS   WITHIN   THE  BASIN"  OP  LAKE  AGASSIZ. 

Table  of  courses  of  glacial  strice. — The  directions  of  the  currents  of  the 
ice-sheet  are  shown  by  its  tracks,  the  furrows  and  striae  which  bowlders 
and  gravel  frozen  in  the  base  of  the  moving  ice  engraved  upon  the  bed- 
rocks over  which  they  passed.  From  these  courses  of  movement  of  the 
ice,  the  areas  of  its  thickest  accumulation  and  consequent  outflow  are 
known.  In  some  districts,  also,  changes  in  the  outlines  of  the  ice  border 
and  in  its  slopes  and  currents  during  its  final  retreat  are  indicated  by 
deflected  glacial  striae  which  run  across  the  earlier  courses.  Occasionally 
two  or  more  sets  of  striae  are  found  intersecting  on  the  same  rock  surface, 
but  more  frequently  the  earlier  and  later  sets  are  preserved  on  separate 
portions  of  the  same  or  contiguous  rock-outcrops.^  The  testimony  of 
these  records  is  so  important  concerning  the  barrier  which  held  Lake 
Agassiz  that  a  table  is  presented  as  an  appendix  of  this  volume,  noting 
the  courses  of  striae  which  have  been  reported  upon  all  the  country  from 
Hudson  Bay,  Lake  Superior,  and  Minnesota  westward  and  northward  across 
the  basin  of  this  glacial  lake. 

Converging  lobes  of  the  ice-sheet  in  Minnesota  and  Manitoba. — The  south- 
westward  striation  in  northeastern.  Minnesota  and  the  southeastward 
striation  in  the  central  and  southern  part  of  that  State  belong  to  two 
convergently  flowing  lobes  of  the  ice-sheet,  partly  corresponding  to  its 
portions  which  earlier  inclosed  the  driftless  area  of  southwestern  Wiscon- 
sin and  united  in  a  continuous   area  of  ice  farther  south      The  central 

'A  most  valuable  classification  of  the  various  types  of  glacial  striation,  planation,  and  emboss- 
ment, with  discussion  of  their  methods  of  urigin  and  of  their  significance  as  evideuce  of  the  prevail- 
ing ice  currents  anil  of  deflections  during  the  glacial  recession,  is  given  in  Professor  Chamberlin's 
memoir,  "The  rock-scorings  of  the  great  ice  invasions,"  Seventh  Annual  Report,  U.  S.  Geol.  Survey,  for 
1885-86,  pp.  147-248,  illustrated  by  .50  figures  in  the  text,  mostly  engraved  from  photographs. 

MON  XXV 9 


130  THE  GLACIAL  LAKE  AGASSIZ. 

line  of  the  western  of  these  ice-lobes  coincided  nearly  with  the  Red  and 
Minnesota  rivers  and  the  upper  Des  Moines,  its  southern  end  being  near 
Des  Moines,  in  central  Iowa.  This  may  be  named  the  Minnesota  lobe  of 
the  ice-sheet.  Farther  west  the  Dakota  lobe  stretched  from  the  Souris 
basin  and  the  region  of  Turtle  Mountain  south  across  the  east  half  of 
North  and  South  Dakota  to  Yankton,  its  central  line  being  along  the 
valley  of  the  James  or  Dakota  River.  In  Manitoba  the  glacial  cuiTents, 
passing  to  the  Minnesota  and  Dakota  ice-lobes,  moved  to  the  south- 
southeast  and  south,  as  noted  at  several  localities  on  the  Winnipeg  River 
above  Lac  du  Bonnet,  on  Lakes  Winnipeg,  Winnipegosis,  Manitoba,  and 
St.  Martin,  at  Stonewall  and  Stony  Mountain,  and  on  the  Assiniboine; 
and  these  currents  are  remarkably  contrasted  with  the  southwestward 
strise  of  the  contiguous  region  of  the  Lake  of  the  Woods  and  the  country 
extending  thence  east  and  north.  These  converging  strise  in  western 
and  eastern  Manitoba  probably  were  engraved  mostly  during  the  reces- 
sion of  the  glacial  boundary,  when  Lake  Agassiz  was  extended  over  the 
greater  part  of  the  Red  River  Valley.  On  the  east  this  lake  appears 
to  have  been  bounded  by  a  vast  ice-lobe  outflowing  from  the  region  of 
Lake  Superior  and  James  Bay  southwest  and  south  to  the  Lake  of  the 
Woods  and  Lake  Itasca,  representing  the  earlier  convergent  ice-lobes  of 
the  northeastern  and  of  the  western  and  southern  portions  of  Minnesota, 
while  on  the  west  it  was  bounded  by  the  representative  of  the  Dakota 
ice-lobe,  then  outflowing  from  the  region  of  Lake  Manitoba  and  Riding 
Mountain  southward  to  the  terminal  moraine  of  Pilot  Knob,  the  north 
side  of  Devils  Lake,  Tm-tle  Mountain,  and  the  Tiger,  Brandon,  and 
Arrow  hills. 

I  Transportation  of  hoiclders.—Neavlj  everywhere  the  greater  part  of  the 
diift  is  derived  from  foiToations  not  far  distant,  varying  from  a  few  miles 
to  25  or  50  miles  away,  in  the  direction  from  which  the  ice-sheet  moved ; 
but  mingled  with  this  material  from  comparatively  near  sources  are  other 
portions,  both  of  the  fine  detritus  and  of  the  small  and  large  rock  masses, 
which  have  been  transported  longer  distances,  as  the  Archean  bowlders  of 
northern  Montana  and  the  upper  Saskatchewan  district,  derived  from  the 
Archean  belt  east  and  north  of  Lake  Winnipeg  and  about  Reindeer  Lake. 


TRANSPOETATION  OP  BOWLDERS.  131 

The  least  distance  from  the  most  western  of  these  bowlders  to  the  margin 
of  the  Archean  belt  is  about  550  miles.  Otlier  bowlders  of  Archean 
origin  which  must  have  traveled  nearly  or  quite  as  far  occur  in  Kansas, 
Missouri,  and  Illinois,  on  the  southwestern  part  of  the  drift-bearing  area  of 
the  United  States.  The  method  of  transportation  of  all  these  is  believed 
by  the  writer  to  have  been  wholly  by  the  slow  currents  of  land  ice. 

Dr.  Robert  Bell  observes  that  the  bowlders  and  pebbles  of  the  drift 
on  the  west  coast  of  Hudson  Bay,  near  the  mouth  of  the  Churchill,  and  on 
the  lower  part  of  the  Nelson,  consist  largely  of  rocks  like  those  of  the 
opposite  eastern  coast  of  Hudson  Bay,  which  is  500  miles  distant.^  But 
the  farthest  known  transportation  of  rock  fragments*  in  the  drift,  recorded 
in  part  by  Dr.  Bell,  whose  observations  are  supplemented  by  my  own,  is 
from  James  Bay  southwest  to  North  Dakota  and  Minnesota.  The  rock 
thus  recognized  is  a  "dark  gray,  granular,  siliceous  felsite  or  graywacke, 
*  *  *  characterized  by  round  spots,  from  the  size  of  a  pea  to  that  of  a 
cricket  ball  or  larger,  of  a  lighter  color  than  the  rest  of  the  rock,  which 
weather  out  into  pits  of  the  same  form."  It  occurs  in  situ,  as  reported  by 
Dr.  Bell,  on  Long  Island,  off  Cape  Jones,  on  the  east  coast  of  Hudson 
Bay  where  it  is  narrowed  to  form  James  Bay,  having  there  a  southwest- 
ward  strike  and  probably  continuing  under  the  sea  for  some  distance  in 
that  direction.  He  notes  that  the  abundance  of  pebbles  and  bowlders  of 
this  rock  is  the  most  remaiJiable  feature  of  the  drift  on  the  west  coast  of 
James  Bay  and  along  the  Attawapishkat,  Albany,  and  Kenogami  rivers, 
and  that  its  fragments  have  been  found  by  him  as  far  west  as  Lonely  Lake 
and  southward  to  Lake  Superior.^  Farther  to  the  southwest  and  south  I 
have  observed  fragments  of  it,  usually  only  a  few  inches  but  in  some 
instances  a  foot  or  more  in  diameter,  occurring  very  rarely  in  the  di'ift  in 
the  northeastern  part  of  North  Dakota,  where  the  largest  piece  ever  found 
by  me  was  about  30  miles  south  of  the  international  boundar}^  and  50 
miles  west  of  the-  Red  River,  and  at  numerous  localities  in  Mimiesota, 
where  it  extends  at  least  as  far  south  as  Steele  County,  75  miles  south  of 
St.  Paul  and  1,000  miles  southwest  of  its  outcrop  north  of  James  Bay. 

■Geol.  Survey  of  Canada,  Report  of  Progress  for  1878-79,  pp.  22,  23  C. 

^Gool.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  II,  for  1886,  p.  36  G. 


132  THE  GLACIAL  LAKE  AGASSIZ. 

DRIFT    DEPOSITS    ON    THE    LACUSTRINE    AREA    AND    THE    ADJOIN- 
ING   REGION. 

The  accompanying  map  (PI.  XVII)  exhibits  the  diverse  formations  of 
drift,  lacustrine,  and  alluvial  deposits,  described  in  this  and. following  chap- 
ters, occurring  within  the  somewhat  thoroughly  examined  prairie  portion 
of  Lake  Agassiz,  with  considerable  tracts  of  the  adjoining  country. 

PI.  Ill,  in  Chapter  I,  drawn  on  a  smaller  scale,  shows  a  greater  extent 
of  the  terminal  moraines,  and  the  courses  of  glacial  striae  (as  noted  in 
Appendix  A),  upon  almost  the  entire  hydrographic  basin  of  Lake  Agassiz, 
with  a  large  area  eastward  to  Hudson  Bay  and  the  upper  Laurentian  lakes. 

Derivation  of  the  drift  from  preglacial  residuary  detritus  and  from  glacial 
erosion. — The  loose  superficial  material  provided  by  preglacial  weathering 
and  stream  erosion  was  generally  plowed  up  and  removed  by  the  ice-sheet, 
being  carried  forward  in  the  direction  of  its  motion  and  mingled  with  other 
material  similarly  gathered  along  the  path  of  the  glacial  current.  Besides 
the  gravel  and  finer  alluvial  detritus  of  valleys  and  a  mantle  of  residuary 
clay,  more  or  less  enveloping  all  the  country,  occasional  bowlders  and  rock 
masses  were  supplied  on  the  higher  lands  by  the  irregular  action  of  the 
preglacial  denudation,  ready  to  be  borne  along  and  deposited  in  the  glacial 
drift.  But  the  ice-sheet  commonly  did  more  than  to  remove  the  loose 
material  before  existing,  as  is  shown  by  rock  surfaces  embossed,  planed, 
and  striated  by  glacial  erosion.  In  general,  far  the  greater  part  of  the 
drift  was  thus  worn  off",  and  most  of  its  bowlders  were  torn  and  plucked 
away,  from  the  rock  floor  over  which  the  ice-sheet  moved,  grinding  it  with 
the  drift  material  contained  in  its  basal  portion  under  the  pressure  of  the 
enormous  weight  of  thousands  of  feet  of  ice.  The  large  proportion  of 
limestone  present  in  the  sand  and  finely  powdered  rock  of  the  drift  in 
regions  of  limestone  formations  demonstrates,  as  Professor  Chamberlin 
has  shown,  that  the  drift  was  chiefly  derived  from  glacial  wearing  of  the 
bed-rocks.^ 

'  U.  S.  Geol.  Survey,  Third  Annual  Report,  p.  312,  and  Sixth  Annual  Report,  memoir  by  T.  C. 
Chamberlin  and  R.  D.  Salisbury,  "The  driftless  area  of  the  Upper  Mississippi,"  pp.  241,247,  255; 
and  Am.  Jour.  Sci.  (3),  Vol.  XXVII,  p.  388,  May,  1884.  Compare  "Composition  of  the  till  or  bowlder- 
clay,"  by  W.  O.  Crosby,  Proceedings  of  Boston  Society  of  Natural  History,  Vol.  XXV,  1890,  pp.  115-140. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XVII. 


JUl  lUS  SIEU   tt  CO   '■ 

MAP  OF  THE  ]m\¥T  DEPOSITS  ON  THE  SOIH^HERN  PORTION  OF  THE  BASIN  OF  LAKE  AGASSIZ . 

Sccile, about  'il?  miles  to  aiiinch. 

Till  i 1     Terminal  iMoraines  M^     Modified  Drift  wUi  Irat-ts  ol'  Till  I I    Deltas  of  Lake Agassiz  I 1 

Other  Lncustrine  ajid.\lluvial  Deposits  I I 


THICKNESS  OF  THE  DEIFT.  133 

It  should  be  added,  however,  that  the  depth  of  the  glacial  erosion  waa 
probably  nowhere  so  great  as  to  change  the  principal  and  grander  topo- 
graphic features  of  the  preglacial  contour.  The  most  important  influence 
of  glacial  action  upon  the  topography  was  usually  the  removal  or  partial 
wearing  away  of  comparatively  small  projecting  knobs,  and  the  filling  up 
of  depressions  and  valleys,  bringing  the  surface  to  a  more  uniform  contour 
than  before  the  Ice  age. 

TJtickness  of  the  drift. — The  thickness  of  the  sheet  of  superficial  depos- 
its overlying  the  bed-rock  upon  the  area  of  Lake  Agassiz  is  shown  by 
wells  to  vary  from  about  125  feet  to  260  feet  or  more  in  Minnesota,  com- 
monly from  200  to  300  feet  in  North  Dakota,  and  from  50  feet  or  less  to 
250  feet  or  more  in  Manitoba. 

At  Herman  and  Moorhead,  Minn.,  the  entire  depth  of  the  drift  is  found 
to  be,  respectively,  124  and  220  feet.  Several  other  deep  wells  in  this  State, 
none  of  them  apparently  extending  to  the  base  of  the  drift,  show  its  thick- 
ness to  be  at  least  260  feet  at  Campbell,  217  feet  at  Ada,  190  to  205  feet 
near  Crookston,  253  feet  at  South  Angus,  and  165  feet  at  St.  Vincent. 

Wells  in  North  Dakota  pass  into  the  strata  underlying  the  drift  at  the 
depth  of  220  feet  in  Fargo,  250  feet  in  Casselton,  310  feet  near  Grandin 
and  Kelso,  and  298  feet  at  Grafton.  A  well  at  Grand  Forks,  265  feet  deep, 
appears  not  to  have  reached  the  bottom  of  the  drift. 

In  Manitoba  the  thickness  of  the  drift  at  West  Selkii'k  is  65  feet ;  in 
Winnipeg  and  St.  Boniface  it  varies  from  30  to  80  feet ;  near  Niverville  it 
is  from  65  to  100  feet ;  in  Dominion  City,  near  Letellier,  and  on  the  Low 
farm,  west  of  Morris,  it  is  at  least  170  to  250  feet,  and  in  West  Lynne  at 
least  108  feet;  at  Rosenfeld  it  is  143  feet;  near  Carman  it  is  about  100 
feet;  and  7  miles  west  of  Portage  la  Prairie,  158  feet.  From  these  records 
it  seems  probable  that  the  thickness  of  these  deposits  upon  the  flat  plain  of 
the  Red  River  Valley  in  Manitoba  averages  about  100  feet,  considerably 
exceeding  this,  to  a  maximum  of  150  to  250  feet,  along  the  central  part 
of  this  area  south  of  the  Assiniboine,  but  not  probably  averaging  more 
than  50  feet  in  the  lower  part  of  the  valley  between  Winnipeg  and  Lake 
Winnipeg,  where  the  higher  portions  of  the  bed-rock  rise  to  the  suiface. 
On  the  Archean  area  of   the  east  part  of   Lake  Agassiz  plentiful    rock- 


134  THE  GLACIAL  LAKE  AGASSIZ. 

outcrops  occui-  about  Rainy  Lake  and  the  Lake  of  the  Woods,  westward 
along  tlie  Canadian  Pacific  Railway  nearly  to  the  Whitemouth  River,  and 
in  the  country  east  of  Lake  Winnipeg ;  and  it  is  probable  that  the  average 
thickness  of  the  superficial  deposits  in  that  extensive  district  is  not  more 
than  30  to  50  feet.  West  of  Lake  Agassiz  many  portions  of  the  plateau 
bordered  by  the  Pembina  Mountain  and  the  Tiger  Hills  have  onlya  small 
depth  of  drift,  ranging  from  a  few  feet  to  20  or  30  feet,  but  in  some  places 
the  drift  appears  to  extend  deeper,  as  shown  by  stream  valleys,  and  its 
average  thickness  may  be  40  feet  or  more. 

Southward  from  Devils  Lake,  upon  the  expanse  crossed  by  the  Shey- 
enne  and  James  rivers,  the  ch'ift  covering  its  eastern  portion,  along  the 
Sheyenne,  continues  thin,  varying  from  10  or  20  to  50  feet  or  more;  but 
farther  west,  along  the  James,  it  is  again  of  considerable  depth,  averaging 
probably  100  feet,  and  ranging  commonly  from  50  to  150  feet  on  moder- 
ately undulating  tracts.  Tlu-oughout  this  plain-like  expanse,  as  generally 
upon  other  parts  of  the  country  adjoining  Lake  Agassiz,  the  drift-sheet 
receives  an  addition  of  probably  30  to  60  feet  along  the  course  of  its 
numerous  admirably  developed  marginal  moraines. 

TILL    OE    BOWLDER-CLAY. 

Till,  also  called  bowlder-clay,  constitutes  the  greater  part  of  the  entire 
sheet  of  supei-ficial  deposits,  both  within  the  area  of  Lake  Agassiz  and 
upon  the  adjoining  country.  It  usually  lies  on  the  striated  bed-rock,  and 
upon  large  areas  it  reaches  thence  upward  to  the  surface;  but  elsewhere 
this  unmodified  glacial  drift  is  covered  by  modified  di'ift,  the  stratified 
gravel,  sand,  and  clay  deposited  by  streams  which  flowed  down  from  the 
ice-sheet  during  its  melting,  or  by  lacustrine  and  fluvial  sediments.  Fully 
half  of  the  area  of  Lake  Agassiz  in  Minnesota  and  North  Dakota  has  a 
surface  of  till.  In  the  part  of  this  lake  area  examined  by  me  in  Manitoba 
its  proportion  is  less,  because  much  of  this  district  is  covered  by  the 
Assiniboine  delta  and  its  associated  lacustrine  beds.  Extensive  tracts  of 
till,  hosvever,  occupy  the  surface  on  the  north  and  east  portions  of  the 
Manitoba  area,  as  north  of  Neepawa,  on  the  east  side  of  the  Big  Grass 
Marsh,  from  the  south  end  of  Lake  Manitoba  eastward  by  Shoal  Lake 


TILL  OE  BOWLDER-CLAY.  135 

nearly  to  the  Red  River  and  Winnipeg  and  south  to  the  Canadian  Pacific 
Railway,  from  East  Selkirk  eastward  along  this  railway,  and  10  miles  east 
of  Emerson,  where  the  flat  plain  of  the  Red  River  Valley  is  bordered  by 
slightly  higher  land.  Till  also  forms  the  surface  of  the  terrace  along  the 
foot  of  the  Pembina  Mountain  escarpment  between  the  international 
boundary  and  Thomhill.  Beneath  the  delta  deposits  of  gravel  and  sand, 
and  along  the  central  portion  of  the  Red  River  Valley,  where  the  surface 
is  commonly  fine  silt  or  clay,  a  sheet  of  till  lies  between  these  sediments 
and  the  bed-rock. 

The  till  is  the  du-ect  deposit  of  the  ice-sheet,  as  is  shown  by  its 
consisting  of  clay,  sand,  gravel,  and  bowlders,  mingled  indiscriminately  in 
an  unstratified  mass,  without  assortment  or  transportation  by  water.  Very 
finely  pulverized  rock,  forming  a  stifi",  compact,  unctuous  clay,  is  its  prin- 
cipal ingredient,  whether  at  great  depths  or  at  the  surface.  It  has  a  dark, 
bluish-gray  color,  except  in  its  upper  portion,  which  is  yellowish  to  a  depth 
that  varies  from  5  to  50  feet,  but  is  most  commonly  between  15  and  30 
feet.  This  difference  in  color  is  due  to  the  influence  of  air  .and  water  upon 
the  iron  contained  in  this  deposit,  changing  it  in  the  upper  part  of  the  till 
from  protoxide  combinations  to  hydrous  sesquioxide.  Another  important 
difference  in  the  till  is  that  its  upper  portion  is  commonly  softer  and  easily 
dug,  while  below  there  is  a  sudden  change  to  a  hai-d  and  compact  deposit, 
which  must  be  picked  and  is  far  more  expensive  in  excavating.  The 
probable  cause  of  this  difference  in  hardness  was  the  pressure  of  the  vast  . 
weight  of  the  ice-sheet  upon  the  subglacial  till,  while  the  upper  part  of 
the  till  was  contained  in  the  ice  and  di'opped  loosely  at  its  melting.  Upon 
each  side  of  Lake  Agassiz  the  till  has  a  moderately  undulating  and  rolling 
surface.  Within  the  area  that  was  covered  by  this  lake  it  has  a  much 
smoother  and  more  even  contour,  and  its  upper  portion,  owing  to  its 
manner  of  deposition  in  this  body  of  water,  sometimes  shows  an  imperfect 
stratification,  with  a  scantier  intermixture  of  bowlders  and  gravel.  Yet 
even  where  it  has  distinct  lamination  it  usually  is  more  like  till  than  like 
ordinary  modified  drift,  and  contains  stones  and  gravel  through  its  entire 
mass. 


136  'J^'HE  GLAOIAL  LAKE  AGASSIZ. 

The  chief  characters  of  the  englacial  upper  portion  of  the  till,  as 
compai-ed  with  the  subglacial  lower  portion,  are  its  looser  texture,  its 
more  plentiful  and  larger  bowlders,  the  prevailingly  angular  and  suban- 
gular  shapes  of  its  bowlders  and  smaller  rock  fragments,  whereas  the}"  are 
mostly  worn  smooth  by  glaciation  in  the  lower  till,  and  the  usually  more 
gravelly  and  sandy  and  less  clayey  composition  of  the  englacial  till,  owing 
to  the  Avashing  away  of  much  of  its  finer  material  by  superglacial  drainage. 
To  these  originally  inherent  characters  we  must  add  the  very  noticeable 
postglacial  change  of  color  of  the  upper  till  already  mentioned.  This 
change  has  generally  extended  through  the  englacial  till,  stopping  at  the 
more  impervious  subglacial  deposit.  Between  the  two  there  is  also  fre- 
quently a  layer  of  subglacial  stratified  gravel  and  sand,  from  a  few  inches 
to  several  feet  thick.  The  extremes  of  thickness  of  the  englacial  till 
appear  to  range  from  almost  nothing  or  only  a  few  feet  for  minima  to 
40  feet  or  more  for  its  maxima  near  massive  terminal  moraines  and  where 
gi-eat  cuiTents  of  the  ice-sheet  converged.^ 

Rock  fragments  and  other  drift  inclosed  in  the  ice  at  a  considerable 
height  above  the  ground  were  borne  forward  without  attrition.  The 
higher  part  of  the  englacial  drift  is  thought  by  the  present  writer  to  have 
supplied  most  of  the  material  forming  the  terminal  moraines,  which,  there- 
fore, have  a  remarkable  profusion  of  bowlders  and  angular  gravel.  When 
the  ice-sheet  was  finally  melted,  its  inclosed  bowlders  were  dropped,  and 
they  now  lie  frequently  as  conspicuous  objects  on  both  the  lower  and 
higher  parts  of  the  land.  Scattered  here  and  there  in  solitude  on  an 
expanse  of  prairie,  or  perched  on  the  sides  and  tops  of  hills  and  moun- 
tains, they  at  first  suggest  transportation  and  stranding  by  icebergs  or 
floe  ice. 

Bowlders  and  gravel  from  Arcliean  and  Paleozoic  formations. — Bowlders 
are  frequent  or  plentiful  in  the  till  throughout  the  area  of  Lake  Agassiz, 
their  abundance  being  nearly  the  same  as  in  the  least  rocky  parts  of  the 
till  of  New  England,  New  York,  and  the  country  surrounding  the  Lauren- 
tian  lakes.  Their  usual  range  in  size  extends  up  to  a  diameter  of  4  or  5 
feet;  but  in  a  few  localities,  especially  in  the  course  of  morainic  belts,  they 

'  BuUetiu,  G.  S.  A.,  Vol.  Ill,  pp.  134-148.     Am.  Geologist,  Vol.  VIII,  pp.  376-385,  Dec,  1891. 


NORTHEASTERN  LIMIT  OF  LIMESTONE  DRIFT.  137 

were  observed  of  all  sizes  up  to  10  or  12  feet  cube.  Generally  as  large  a 
proportion  as  99  per  cent  of  the  bowlders  exceeding  1  foot  in  diameter 
consists  of  Archean  granite,  gneiss,  and  schists,  being  derived  from  the 
Archean  area  on  the  northeast  and  north.  With  these  are  occasional  lime- 
stone blocks,  derived  from  the  belt  of  Paleozoic  limestones,  constituting  on 
the  average  perhaps  nearly  1  per  cent  of  the  large  rock  fragments  of  the 
drift.  The  bedded  and  jointed  character  of  the  limestones  has  prevented 
their  supplying  nianj^  large  bowlders  in  comparison  with  the  more  massive 
crystalline  Archean  rocks,  while  yet  usually  about  half  of  the  smaller 
cobbles  and  pebbles  in  the  till  and  in  gravel  and  sand  deposits  are  from 
these  Paleozoic  limestones.  Upon  the  Cretaceous  area  a  considerable  pro- 
portion of  the  gravel  and  cobbles  is  derived  from  the  Fort  Pierre  shale, 
but  this  formation  supplies  no  large  blocks. 

Northeastern  limit  of  limestone  drift. — East  of  Lake  Winnipeg  and 
northeast  of  a  line  drawn  from  this  lake  southeastward  by  Lac  du  Bonnet 
on  the  Winnipeg  River  and  across  the  Lake  of  the  Wood's  to  the  west  end 
of  Rainy  Lake  and  onward  to  Vermilion  Lake,  both  bowlders  and  gravel 
of  limestone  are  absent  or  exceedingly  rare.  This  line  probably  marks 
the  farthest  extent  ever  attained  by  the  glacial  currents  which  moved 
south-southeast  in  the  vicinity  of  Winnipeg  and  at  Black  Bear  Island,  near 
the  Narrows  of  Lake  Winnipeg,  carrying  debris  from  the  limestone  region 
of  the  Manitoba  lakes. 

It  is  also  very  remarkable  that  the  same  line  divides  an  area  of  very 
thin  drift  on  its  northeast  side  from  the  area  of  very  thick  drift  which 
thence  extends  southwestward  across  all  western  Minnesota,  the  southern 
part  of  Lake  Agassiz,  and  the  region  of  the  Sheyenne  and  James  rivers 
to  the  Missouri  Coteau. 

Localities  of  very  abundant  and  large  bowlders. — The  following  localities 
may  be  mentioned  as  having  especially  abundant  bowlders :  On  the  slope 
of  the  Pembina  Mountain,  in  township  3,  range  6,  Manitoba,  between 
Morden  and  Thornhill,  very  plentiful  and  large  bowlders  are  spread  upon 
an  area  of  several  square  miles,  as  noted  in  the  description  of  the  Tintah 
beaches.  The  sides  of  Star  Mound,  Manitoba,  especially  those  fticing  the 
north  and  northeast,  are  strewn  vv-ith  a  multitude  of  Ijowlders,  ucailx'  all 


138  THE  GLACIAL  LAKE  AGASSIZ. 

granitic,  of  all  sizes  up  to  5  feet  in  diameter  or  rarely  larger.  These 
were  probably  combed  out  of  the  ice-sheet  in  its  passage  over  this  hill. 
Comparatively  few  bowlders  occur  on  the  small  flat  area  at  its  top.  Pilot 
Mound,  an  equally  prominent  hill  seen  from  this  in  looking  northwest,  is, 
like  Star  Mound,  a  knob  of  Cretaceous  shale  with  thin  covering  of  drift, 
but  it  has  no  such  unusual  profusion  of  bowlders  on  its  slopes.  Rock 
Lake,  through  "which  the  Pembina  flows,  derives  its  name  from  the  remark- 
able abundance  of  bowlders,  mostly  granitic,  up  to  6  feet  or  more  in 
diameter,  bordering  its  shores ;  and  along  a  distance  of  1  or  2  miles  west 
from  this  lake  the  Pembina  Valley  is  much  encumbered  with  bowlders, 
which  in  some  places  are  accumulated  upon  small  morainic  ridges  and 
knolls. 

The  largest  bowlder  observed  within  the  area  of  Lake  Agassiz  south 
of  the  international  boundary  has  given  name  to  White  Rock  station,  in  the 
northeast  corner  of  South  Dakota,  11  miles  north  of  Lake  Traverse.  This 
bowlder,  lying  50  feet  west  of  the  railway,  at  a  distance  of  about  25  rods 
north  of  the  station,  measures  18  by  12  feet,  with  a  height  of  5 J  feet.  It 
is  a  medium-grained,  massive,  flesh-colored  granite,  weathering  to  a  wliitish 
gray. 

Another  bowlder  of  nearly  equal  size  lies  about  50  rods  west  of  the 
Herman  beach,  in  or  near  section  12,  township  140,  range  46,  Minnesota, 
some  6  miles  north  of  Muskoda.  Its  dimensions  are  15  by  12  by  5  feet, 
and  its  top  is  1,095  feet  above  the  sea.  It  is  gneiss,  minutely  porphyritic, 
with  white  feldspar  crystals  up  to  an  eighth  or  a  quarter  of  an  inch  long. 

A  somewhat  larger  block,  exceeding  any  other  noted  during  my  survey 
of  Lake  Agassiz  and  the  adjoining  region,  lies  in  the  northwest  quarter 
of  section  9,  township  1,  range  4  east,  Manitoba,  on  the  low  ridge  10  miles 
east  of  Emerson.  It  is  dark-gray  gi'anitoid  gneiss,  22  feet  long,  8  to  14 
feet  wide,  and  projecting  2  to  5  feet  above  the  surface.  Among  the  other 
plentiful  bowlders  of  that  Aacinity  none  was  seen  exceeding  7  or  8  feet  in 
dimensions.  Like  many  of  the  smaller  bowlders  throughout  this  prairie 
region,  this  block  is  surrounded  by  a  slight  depression  1  to  3  feet  below 
the  adjoining  groimd ;  and  a  careful  examination  shows  that  some  of  its 
projecting  corners  and  edges  are  smoothly  polished.     These  depressions 


TWELVE  TERMINAL  MORAINES.  139 

were  formed  by  the  trampling-  and  pawing-  of  buffaloes  in  rubbing  on  the 
bowlders,  which  were  thereby  sometimes  worn  and  polished  as  perfectly  as 
could  be  done  by  art.  ^ 

TERMINAL    MORAINES. 

Exploration  of  the  terminal  moraines  in  the  northeast  edge  of  South 
Dakota,  accumulated  on  the  west  margin  of  the  Minnesota  lobe  of  the  ice- 
sheet,  northward  to  the  Head  of  the  Coteau  des  Prairies,  was  included  in 
the  work  of  the  writer  during  1880  for  the  Minnesota  Geological  Survey. 
The  three  outer  moraines  are  typically  developed  and  distinctly  separated 
in  that  portion  of  their  course,  as  well  as  through  the  adjoining  southwest 
part  of  Minnesota ;  and  from  their  description  for  this  district  ^  they  have 
been  denominated  by  Professor  Chamberlin  the  Altamont,  Gary,  and  Ante- 
lope moraines.  Besides  these,  nine  others,  to  a  total  of  twelve  in  all  (as 
shown  on  Pis.  Ill  and  XVII),  lying  along  a  large  part  of  their  extent  in 
successive  order  from  south  to  north,  and  apparently  marking  consecutive 
stages  in  a  wavering  recession  of  the  ice-sheet,  are  recognized  in  Minnesota 
and  receive  names  in  the  annual  and  final  reports  of  the  State  survey  from 
locahties  where  they  are  notably  prominent  or  distinct.  In  western  Min- 
nesota they  seem  to  constitute  a  simple  series,  each  in  order  advancing  from 
south  to  north  and  northeast  being  of  somewhat  later  formation  than  the 
one  preceding ;  but  in  the  central  and  eastern  portions  of  the  State,  from 
the  Leaf  Hills  southeast  to  MinneapoHs  and  St.  Paul,  and  in  their  course 
eastward  into  northern  Wisconsin,  consecutive  moraines  are  merged  together, 
and  even  the  later  are  found  overlapping  the  earlier  in  the  series. 


'Notes  of  the  wide  area  over  whicli  such  bowlders  polished  by  buffaloes  are  found,  and  of 
other  traces  of  these  animals  still  visible  ou  the  prairies  and  plains,  from  which  they  have  so  recently 
vanished,  are  given  in  Geology  of  Minnesota,  Vol.  II,  p.  516. 

Occasionally  a  bowlder  worn  by  the  rubbing  of  buffaloes  has  been  pushed  back  and  forth  by 
them  while  the  surrounding  hollow  was  being  formed  by  their  pawing  and  by  the  winds  blowing 
away  the  dust  from  it,  until  the  rock  has  been  thus  undermined  and  lowered  evidently  at  least  3  or  4 
feet  below  its  original  position,  so  that  its  top  now  lies  beneath  the  general  level  of  the  land.  Among 
several  examples  of  this  result  seen  by  me,  one  may  be  noted  which  was  found  about  60  feet  northwest 
of  the  quarter-section  stake  between  sections  26  and  35,  Mekinock,  Grand  Forks  County,  N.  Dak. 
This  bowlder,  weighing  several  tons,  measures  about?  feet  in  length  and  5  feet  in  width,  and  stands 
up  U  to  2  feet  out  of  the  ground;  yet  it  is  so  situated  in  a  bowl  shaped  hollow,  30  to  40  feet  in 
diameter  and  3  feet  or  more  in  depth,  that  the  top  of  the  rock  is  1+  feet  below  the  uniform  level  sur- 
face on  all  Bides  around  the  hollow.  It  is  a  light-gray,  rather  coarse-grained  hornblendic  granite, 
very  compact  and  not  affected  by  weathering;  and  its  corners  and  edges  are  finely  polished. 

"Geol.  and  Nat.  Hist.   Survey  of  Minnesota,  Ninth  Aunu.al  Report,  for  1880;  Final  Renort    Vols 
I  and  II.  '  I       ,  ■ 


140  THE  GLACIAL  LAKE  AGASSIZ. 

Farther  to  the  west  the  terminal  moraines  of  South  Dakota,  and  of 
North  Dakota  west  of  the  James  River  and  north  to  the  Northern  Pacific 
Raihoad,  have  been  mapped  b}'  Prof  J.  E.  Todd  for  the  United  States 
Geological  Survey.  To  give  a  more  complete  \'iew  of  these  moraines 
through  the  region  of  Lake  Agassiz,  notes  based  on  his  map  and  several 
published  papers  are  included  in  the  present  monograph.  My  observations 
of  the  outer  moraines  on  the  Coteau  des  Prairies  from  Iowa  to  the  north- 
east part  of  South  Dakota  and  on  the  Coteau  du  Missouri  in  the  northwest 
part  of  North  Dakota  are  thus  connected  and  correlated  through  Professor 
Todd's  exploration  of  the  successive  boundaries  of  the  intervening  Dakota 
lobe  of  the  ice-sheet. 

The  moraines  of  the  Tiger,  Brandon,  and  Arrow  hills  in  Manitoba, 
mapped  by  the  Avriter  in  1887,  seem  probably  contemporaneous  with  the 
most  northern  morainic  belts  in  Minnesota,  and  it  is  evident  that  in  both 
districts  they  belong- to  the  time  of  the  uppermost  in  the  series  of  the  Her- 
man beaches,  the  first  and  highest  of  the  Avell-marked  shore-lines  of  this 
glacial  lake.  Though  these  moraines  of  southwestern  Manitoba  and  north- 
ern Minnesota  are  the  tenth  and  eleventh,. the  latest  formed,  in  the  series  of 
moraines  here  described,  they  mark  a  much  earlier  stage  of  the  glacial 
retreat  than  the  terminal  moraine  observed  by  Dr.  Robert  Bell  ^  as  crossed 
by  the  Hill,  Nelson,  and  Churchill  rivers,  about  midway  between  Lake 
Winnipeg  and  Hudson  Bay,  which  may  well  belong  to  the  time  of  the 
Campbell  beaches  or  later,  while  the  line  of  morainic  islands  reported  by 
Mr.  A.  P.  Low"  along  an  extent  of  about  200  miles  from  south  to  north 
and  north-northwest  in  James  Bay  was  certainly  formed  after  Lake  Agassiz 
began  to  outflow  northeastward,  perhaps  after  it  was  lowered  to  its  present 
representative.  Lake  Winnipeg. 

The  twelve  moraines  of  Minnesota  are  doubtless  correlative  with  the 
similarly  luiraerous  moraines,  partly  simple,  with  approximately  parallel 
courses,  and  partly  complicated  in  their  arrangement  by  interblending 
and  overlapping,  which  have  been  recently  traced  by  Mr.  Frank  Leverett, 
passing  southward  from  Wisconsin  along-  the  east  side  of  the  driftless  area 

1  Bulletin,  G.  S.  A.,  Vol.  I,  pp.  303,  306. 

^Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  Ill,  for  1887-88,  pp. 
25-36  J  and  62  J. 


MORAINES  FORMED  BEFORE  LAKE  AGASSIZ.  141 

and  running  in  great  loops,  the  boundaries  of  lobes  of  the  ice-sheet,  across 
Illinois,  Indiana,  and  Ohio.  These  are  embraced  within  a  strip  of  country 
of  similar  width  with  that  of  Minnesota,  Iowa,  and  the  Dakotas,  which, 
though  200  or  300  miles  wide,  is  yet  only  a  minor  part  of  the  drift-covered 
area  of  this  continent.  For  the  interior  of  this  area  the  observations  of 
Bell  and  Low  give  us  good  assurance  that  nearly  an  equal  profusion  of 
marginal  moraines,  recording  step  by  step  the  wavering  departure  of  the 
ice-sheet,  await  exploration  in  all  the  region  northeast  and  north  from 
Minnesota  and  the  Great  Lakes  to  Hudson  Bay,  and  from  northern  Penn- 
sylvania, New  Jersey,  Long  Island,  Marthas  Vineyard,  Nantucket,  and 
Cape  Cod  to  the  Laurentide  highlands,  north  of  Montreal  and  Quebec. 

EARLIER   MORAINES  FORMED  BEFORE  THE  SEGINXISG    OF  LAKE   AOASSIZ. 

When  the  North  American  ice-sheet  attained  its  greatest  area,  and 
during  its  later  lowan  and  Wisconsin  stages,  its  southern  portion,  from 
Lake  Erie  to  the  Missouri  River,  consisted  of  vast  lobes,  one  of  which,  at 
the  beginning  of  the  Wisconsin  stage  of  accumulation  of  moraines,  reached 
from  central  and  western  Minnesota  south  to  central  Iowa.  This  ]\Iinne- 
sota  lobe  then  ended  near  Des  Moines,  and  its  margin  was  marked  by  the 
first  or  Altamont  moraine,  lying  upon  the  Coteau  des  Prairies  and  in  part 
forming  its  crest.  When  the  second  or  Gary  moraine. was  formed,  it  ter- 
minated on  the  south  at  Mineral  Ridge,  in  Boone  County,  Iowa.  At  the 
time  of  the  third  or  Antelope  moraine  it  had  farther  retreated  to  Forest 
City  and  Pilot  Mound,  in  Hancock  County,  Iowa.  The  fourth  or  Kiester 
moraine  was  formed  when  the  southern  extremity  of  the  ice-lobe  had 
retreated  across  the  south  line  of  Minnesota  and  halted  a  few  miles  from 
it  in  Freeborn  and  Faribault  counties.  The  fifth  or  Elysian  moraine,  cross- 
ing southern  Lesueur  County,  Minn.,  marks  the  next  halting  place  of  the 
ice.  At  the  time  of  formation  of  the  fifth  moraine  the  south  end  of  the 
ice-lobe  had  been  melted  back  180  miles  from  its  earlier  extent,  shown  by 
the  Altamont  moraine,  and  its  southwest  side,  which  at  first  rested  on  the 
Coteau  des  Prairies,  had  retired  30  to  50  miles  to  the  east  side  of  Big  Stone 
Lake  and  the  east  part  of  Yellow  Medicine  County. 

During  its  next  stage  of  retreat  the  Minnesota  ice-lobe  was  melted 
away  from  the  whole  of  Lesueur  County,  and  its  southeast  extremity  was 


142  THE  GLACIAL  LAKE  AGASSIZ. 

withdrawn  to  Waconia,  in  Carver  County,  where  it  again  halted,  forming 
its  sixth  or  Waconia  moraine.  This  records  the  position  of  the  front  of 
the  ice-sheet  immediately  before  its  continued  recession  gave  place  for  the 
beginning  of  Lake  Agassiz.  It  will  therefore  be  described  somewhat  in 
detail  along  its  course  adjacent  to  this  glacial  lake. 

SIXTH   OR  WACONIA  MORAINE. 

Between  the  fifth  and  sixth  moraines  the  southeast  end  of  the  Minne- 
sota ice-lobe  retreated  from  Elysian  to  Waconia,  a  distance  of  about  40 
miles  from  south  to  north,  uncovering  the  lower  portion  of  the  Minnesota 
Valley  and  finally  di-aining  the  glacial  lake  of  the  Blue  Earth  and  Minne- 
sota basins,  which  had  outflowed  southward  in  its  highest,  early  stages  by 
Union  Slough  in  Iowa  to  the  East  Des  Moines  River,  and  later  to  the  east 
by  the  Cannon  River.  The  advance  of  the  east  side  of  this  ice-lobe  at  the 
time  of  the  Kiester  and  Elysian  moraines  beyond  its  previous  limit,  by  an 
incursion  from  Wright  County  to  Chisago  County  and  the  edge  of  Wiscon- 
sin, had  been  followed  by  a  withdrawal  from  the  greater  part  of  the  area 
thus  acquired,  until  at  the  time  of  the  sixth  moraine  the  most  eastern  por- 
tion of  the  ice  margin  was  accumulating  the  prominent  drift  hills  close  east 
and  north  of  Elk  River,  in  Sherbui-ne  County.  The  glacial  recession  there 
from  east  to  west  and  southwest  between  the  Elysian  and  Waconia  moraines 
appears  to  have  been  also  about  40  miles.  A  long  indentation  of  the  ice- 
sheet,  between  its  Minnesota  and  Lake  Superior  lobes,  was  melted  back 
during  the  same  interval,  the  apex  of  this  reentrant  angle  being  carried 
from  southeastern  Stearns  County  50  miles  west  to  Lake  Whipple  and 
Glenwood,  in  Pope  County.  But  in  some  places  the  ice  border  north  and 
east  of  Waconia  had  probably  retreated  no  more  than  a  few  miles,  and  on 
the  southwest  side  of  the  Minnesota  lobe,  in  Redwood,  Yellow  Medicine, 
Chippewa,  Swift,  and  Big  Stone  counties,  there  was  only  slight  recession  of 
the  ice,  and  the  Elysian  and  Waconia  moraines  seem  to  be  blended,  though 
they  form  together  only  inconspicuous  marginal  deposits.^ 

'  Geology  of  Minnesota,  Vol.  II,  pp.  642,  625,  440,  463,  484, 487,  488,  233,  415, 105, 106  [Waconia],  128 
166,  213,  516;  Vol.  I,  pp.  606,  621.  (These  citations  are  in  the  order  from  east  to  west  for  the  areas  sev- 
erally described  in  the  chapters  of  the  Minnesota  reports  treating  of  separate  counties.) 


THE  SIXTH  OR  WACONIA  MORAINE.  143 

After  passing  northwest  across  Lake  Traverse  and  the  Head  of  the 
Coteau  des  Prairies,  the  Waconia  moraine  aj^pears  to  be  merged  with  the 
two  preceding-  Elysian  and  Kiester  moraines  in  the  conspicuous  belt  of 
drift  hills  that  extends  from  the  line  dividing  South  and  North  Dakota 
northward  between  Straubville  and  Crescent  Hill,  between  Nicholson  and 
Oakes,  and  along  the  east  side  of  Bear  Creek,  to  the  southeast  part  of 
township  135,  range  59.  Thence  it  turns  west  and  northwest  a  few  miles, 
beyond  which  it  runs  again  northward  tlirough  the  west  part  of  township 
136,  range  59,  the  most  northeastern  of  Lamoure  County,  where  it  forms 
a  narrow  belt  of  knolls  and  hills,  rising  40  to  60  feet  above  the  nearly 
level  plain  on  each  side. 

In  Barnes  County,  running  42  miles  from  south  to  north,  this  moraine 
is  distinct  and  well  developed,  being  divided  from  the  next  earlier  and  later 
moraines  of  the  series  by  smoothl)'  iindulating  and  in  large  part,  nearly 
level  belts  of  till,  which  vary  in  width  from  2  to  3  miles  to  a  maximum  of 
about  8  miles  on  the  west  and  12  miles  on  the  east,  the  separation  from  the 
seventh  or  Dovi'e  moraine  being  on  the  average  the  wider  of  the  two. 
The  Waconia  moraine  enters  Barnes  County  at  the  middle  of  the  south 
side  of  township  137,  range  59,  and  curving  northeastward  passes  through 
sections  34,  26,  and  24,  in  a  belt  of  typical  knolls  and  hills  25  to  75  feet 
high,  very  rough  in  their  outlines  and  profusely  strewn  with  bowlders,  to 
the  east  line  of  this  township,  where  the  apex  of  a  reentrant  angle  of  this 
belt  almost  touches  the  Dovre  moraine,  which  rises  to  equal  or  greater 
prominence  in  the  adjoining  township.  A  plain  of  overwashed  gravel  and 
sand,  deposited  just  outside  the  ice  border  in  the  indentation  of  the  Waconia 
moraine,  is  crossed  by  the  road  on  the  west  line  of  sections  23,  14,  and  11, 
township  137,  range  59,  thinly  covering  the  underlying  till,  which  is  occa- 
sionally exposed,  with  its  projecting  bowlders,  in  slight  depressions.  Turn- 
ing by  a  right  angle,  this  moraine  runs  northwestward  through  sections  13, 
11,  and  3,  rising  25  to  50  or  75  feet  above  the  general  level.  In  the  north- 
east quai'ter  of  section  3,  a  lake  bed,  wholly  dry  in  August,  1889,  lies  at 
the  northeast  base  of  these  hills,  and  a  belt  about  a  half  mile  wide,  next  to 
the  north,  is  moderately  rolling  till,  beyond  which  a  second  belt  of  morainic 
hills  similar  to  the  foregoing  and  parallel  with  it,  a  fourth  to  a  third  of  a 


144  THE  GLACIAL  LAKE  AGASSIZ. 

mile  wide,  runs  northwestward  through  the  southwest  quarter  of  section  35, 
township  138,  range  59.  This  twofold  condition  of  the  Waconia  moraine 
is  observable  along  a  distance  of  3  or  4  miles.  In  sections  32  and  29  the 
moraine  tiirns  to  the  north  and  continues  through  the  middle  of  the  west 
half  of  this  township  in  hills  and  short  south-to-north  ridges  25  to  60  feet 
above  the  adjoining  nearly  level  inter-morainic  surface  of  till.  The  width 
of  the  hilly  belt  here  and  north-northeastward  through  sections  33,  28,  21, 
and  22,  township  139,  range  59,  is  about  a  mile;  but  for  the  next  4  miles 
north  it  expands  to  a  width  of  2  or  3  miles  and  is  conspicuously  displayed 
in  steep  hills  50  to  150  feet  high,  to  the  apex  of  another  reentrant  angle  in 
sections  33  and  34,  township  140,  range  59,  2  to  3  miles  south  of  Hobart. 
Thence  the  moraine  again  turns  by  a  right  angle,  taking  a  westward  course, 
parallel  with  the  Northern  Pacific  Railroad  and  about  2  miles  south  of  it, 
through  the  south  edge  of  township  140,  range  60,  where  its  hills  cover 
an  average  width  of  1  mile  and  rise  50  to  75  feet  above  the  smoothly 
undulating  expanse  of  till  on  each  side. 

The  Northern  Pacific  Railroad  crosses  the  Waconia  moraine  close 
west  of  Eckelson,  where  it  has  a  width  of  about  a  mile,  marked  by  a 
rolling  and  partly  knolly  contom-,  with  elevations  25  to  50  feet  above  the 
hollows.  Within  a  mile  west  of  the  morainic  belt  the  railroad  crosses  an 
ancient  watercourse,  a  fourth  to  a  half  of  a  mile  wide,  extending  from 
north  to  south,  occupied  by  a  lake  on  the  north  side  of  the  railroad  and 
by  a  marsh  on  the  south.  Both  are  bordered  by  bluffs  which  rise  steeply 
about  40  feet  to  the  general  level.  This  lake  is  one  of  a  series  that 
extends  6  miles  south-southwest,  occupying  portions  of  this  old  water- 
course, but  intervening  portions  and  its  farther  continuation  southward 
are  mostly  filled  with  the  glacial  diift.  Lake  Eckelson  and  a  series  of 
smaller  lakes,  reaching  5  miles  south  to  Walker  Lake,  mark  a  second  and 
parallel  watercourse,  similarly  enveloped  in  other  portions  by  the  general 
drift  sheet.  The  north  end  of  a  third  series  or  chain  of  lakes  of  the  same 
kind,  about  6  miles  long,  is  crossed  by  the  railroad  a  mile  east  of  Sanborn; 
and  a  fourth  is  indicated  by  a  long  lake  extending  south  from  the  railroad 
near  Hobart.  The  first  of  these  chains  of  lakes  lies  wholly  outside  the 
Waconia  moraine,  but  the  others  are  crossed  by  the  east-to-west  portion  of 


THE  SIXTH  OR  WAOONIA  MORAINE.  145 

this  moraine  south  of  Hobart,  Sanborn,  and  Eckelson.  They  probably 
have  had  a  history  hke  that  of  the  Spiritwood  series  of  lakes,  several 
miles  farther  northwest,  and  of  the  similar  chains  of  lakes  extending  from 
north  to  south  in  Martin  County,  Minn.,  which  are  believed  to  occupy  the 
unfilled  parts  of  preglacial  or  perhaps  interglacial  channels  of  drainage.^ 

Beyond  Eckelson  this  moraine  extends  north-northwestward  as  a  roll- 
ing and  knolly  belt,  inconspicuous  in  any  distant  view,  to  the  southeast 
part  of  township  142,  range  61,  about  10  miles  east  of  Spiritwood  Lake. 
There  it  is  moderately  rolling  and  occasionally  hilly,  a  third  to  a  half  of 
a  mile  wide,  with  more  bowlders  than  the  adjoining  lower  and  only 
slightly  undulating  surface,  both  being  till.  Curving  north-northeastward, 
it  passes  through  sections  14,  12,  and  1  of  this  township,  being  well 
marked  in  the  east  part  of  section  1  as  a  belt  of  low  morainic  knolls,  a 
quarter  of  a  mile  wide.  OnwiJrd  through  the  next  6  miles  northeast  to 
the  south  part  of  section  11,  township  143,  range  60,  this  moraine  forms  a 
belt,  a  half  mile  to  1  mile  -^yide,  of  knolls  and  scattered  steep  hills,  partly 
composed  of  kame  gravel  and  sand,  with  few  bowlders,  rising  40  to  75 
feet  above  the  general  level,  as  conspicuously  seen  from  Dazey.  In  sec- 
tion 11  its  course  seems  again  to  be  deflected  nearly  by  a  right  angle, 
passing  thence  northwest  and  north  through  township  144,  range  60,  to 
the  vicinity  of  the  Helena  farm  in  section  29,  township  145,  range  60; 
but  along  this  distance  it  is  marked  only  by  a  rolling  contour,  with  no 
prominent  elevations. 

Continuing  northward  tlirough  Griggs  County,  the  Waconia  moraine 
becomes  gradually  more  knolly  and  hilly,  with  increasing  proportion  of 
bowlders,  to  its  magnificent  development  in  townships  147  and  148,  range 
60,  passing  close  east  of  Lake  Sibley  and  west  of  the  beautiful  Lakes  Addie 
and  Jessie,  to  Red  Willow  Lake.  Along  the  distance  of  10  miles  adjoining 
these  lakes  the  irregularly  piled  masses  of  morainic  di-ift,  strewn  with  many 
bowlders,  rise  100  to  200  feet  above  the  lakes,  giving  a  measure  of  boldness 
and  even  grandeur  to  the  scenery,  such  as  is  rare  in  this  plain  and  prairie 
region.  West  of  Lake  Sibley  the  fine  agricultural  tract  of  Blooming 
Prairie  has  a  nearly  level  surface  upon  a  width  of  about  10  miles,  includ 

'  Geology  of  Minnesotii,  Vol.  I,  pp.  479-485,  with  PI.  18. 
MON  XXV 10 


146  THE  GLACIAL  LAKE  AGASSIZ. 

ing  township  146  and  the  south  part  of  township  147,  range  61,  beyond 
which,  northward,  this  smooth  area  of  lowland,  dividing  the  Waconia  and 
Elysian  moraines,  narrows  into  a  belt  only  about  a  mile  wide  in  the  south- 
east part  of  township  148,  range  61,  called  Colemans  Valley.  At  the 
north  end  of  this  valley,  on  the  west  side  of  Red  Willow  Lake,  these 
two  moraines  meet,  and  thence  pass  in  a  united  morainic  belt  west  and 
northwest  to  the  Washington  Lakes,  the  Sheyenne  River,  and  the  Indian 
reservation  south  of  Devils  Lake. 

MORAINES    CONTEMPORANEOUS    WITH    LAKE    AGASSIZ. 

The  seventh  or  Dovre  moraine  marks  a  pause  in  the  glacial  recession 
when  the  southeast  end  of  the  Minnesota  ice-lobe  rested  on  Kandiyohi 
County.  At  this  time  Lake  Agassiz  had  begun  to  exist,  the  south  end  of 
the  Red  River  Valley  having  been  uncovered  from  the  ice.  Probably 
nearly  all  of  the  southern  half  of  Minnesota  was  then  divested  of  its  ice 
mantle,  while  nearly  all  of  the  northern  half  was  still  ice-covered,  the 
glacial  boundary  across  the  State  passing  in  an  approximately  east-to-west 
course. 

B}^  its  next  recessions  the  ice  border  was  withdrawn  to  the  eighth  or 
Ferg-us  Falls  moraine  and  the  nintli  or  Leaf  Hills  moraine.  These  are 
partly  merged  together  in  the  prominent  accumulations  of  the  Leaf  Hills, 
which  reach  in  a  semicircle  from  Fergus  Falls  to  the  southeast,  east,  and 
northeast,  a  distance  of  50  miles,  marking  the  southern  limits  of  this  ice- 
lobe  when  it  terminated  half  way  between  the  south  and  north  borders 
of  Minnesota.  During  the  formation  of  the  tenth  or  Itasca  moraine,  and 
of  the  eleventh  or  Mesabi  moraine,  the  ice  border  crossed  the  lake  region 
at  the  head  of  the  Mississippi.  Farther  north  the  twelfth  or  Vermilion 
moraine,  discovered  and  mapped  by  the  present  writer  in  1893  during 
work  for  the  Minnesota  Geological  Survey,  passes  by  the  south  side  of  Ver- 
milion, Pelican,  and  Net  lakes.  Later  moi'aines,  formed  at  times  of  halt  or 
readvance,  interrupting  the  recession  of  the  ice-sheet  between  northern 
Minnesota  and  Hudson  Bay,  have  been  observed  in  only  a  few  places; 
but  I  believe  that  they  exist  and  will  be  continuously  mapped  when  the 
glacial  drift  of  that  wooded  and  very  scantily  inhabited  region  shall  be 


MORAINES  CONTEMPORANEOUS  WITH  LAKE  AGASSIZ.         147 

fully  explored.  The  manj^  beaches  of  Lake  Agassiz,  all  showing  an  ascent 
northward  when  compared  with  the  level  of  the  present  time,  but  with  this 
ascent  gradually  decreased  during  the  successive  stages  of  the  lake,  prob- 
ably find  their  explanation  in  the  manner  of  retreat  of  the  ice  in  Canada, 
interrupted  there,  as  farther  south,  by  pauses  and  the  formation  of  moraines. 
The  following  are  notes*  of  the  five  moraines  already  mapped  which 
cross  the  expanse  of  Lake  Agassiz,  being  conspicuous  upon  each  side  of 
this  lake,  but  faintly  developed  or  lost  on  the  lacustrine  area: 

SEVENTH    OR    DOVRE    MORAINE, 

The  Dovre  moraine  is  prominent  in  Stearns,  Douglas,  Pope,  and 
Kandiyohi  counties,  Minn.  Its  distinctive  name  is  taken  from  its  hills  in 
Dovre,  Kandiyohi  County,  to  which  the  southeast  extremity  of  the  Min- 
nesota lobe  of  the  ice-sheet  had  been  withdrawn  west-northwestward  about 
70  miles  from  Waconia  during  the  interval  between  the  sixth  and  seventh 
moraines.  In  Pope  and  Douglas  counties  an  area  about  25  miles  wide, 
from  Glenwood  north  to  Miltona  and  Spruce  Hill  townships,  was  probably 
uncovered  by  this  glacial  recession.  But  considerable  portions  of  the  ice 
border  in  its  general  course  at  this  time  from  east  to  west  across  central 
Minnesota  had  receded  only  a  few  miles  between  these  moraines.  Indeed, 
they  seem  to  be  merged  together  north  of  Richmond,  in  Stearns  County, 
and  from  Barsness,  in  Pope  County,  to  Mount-  Tom,  about  9  miles  north- 
northeast  of  the  Dovre  Hills.  Again,  in  Big  Stone  County,  a  single  belt 
of  somewhat  rolling  till,  5  to  8  miles  wide,  seems  representative  of  the 
Elysian,  Waconia,  and  Dovre  moraines  combined.  In  the  wooded  country 
east  from  Little  Falls,  Minn.,  to  the  sources  of  the  St.  Croix  River  in  Wis- 
consin, this  moraine  has  not  been  definitely  traced.^ 

Crossing  Richland  and  Sargent  counties,  in  the  southeast  comer  of 
North  Dakota,  the  Dovi-e  moraine  is  well  developed  in  knolls,  hills,  and 
short  ridges  of  till,  covering  a  belt  from  a  half  mile  to  2  miles  in  width,  with 
abundant  bowlders  and  characteristically  rough  contour.  On  the  south- 
west side  of  Taylor  Lake,  near  Hankinson  railway  sta'tion,  these  rough 

'Geology  of  Minnesota,  Vol.  II,  pp.  642,  625,  581-585,605,  446-448,464,  475-478,482-488  (Including 
a  general  description  of  the  characteristic  features  of  the  terminal  moraines  of  Minnesota),  224-226 
[Dovre],  233,  213;  and  Vol.  I,  p.  621.     (The  order  of  citation  is  geographical,  from  east  to  west.) 


148  THE  GLACIAL  LA[<:E  AGAS31Z. 

di-ift  hills  rise  to  heights  50  to  150  feet  above  this  lake,  or  1,100  to  1,200 
feet  above  the  sea.  Thence  a  bowlder-strewn,  rolling',  and  knolly  surface, 
with  numerous  small  lakes,  extends  west  along  the  south  side  of  the  Great 
Northern  Railway  to  prominent  morainic  hills,  50  to  100  feet  in  height, 
which  extend  about  7  miles  from  east  to  west  close  south  of  Greneseo  and 
Cayuga.  In  the  east  part  of  township  130,  range  54,  this  moraine  cui'ves 
to  the  north,  passing  about  a  mile  west  of  Cayuga  and  Ransom,  and  north- 
northeastward  through  the  northwest  part  of  township  131,  range  53. 
From  near  the  northwest  corner  of  this  township  it  runs  to  the  northwest 
diagonally  across  township  132,  range  54,  passing  close  west  of  Milnor, 
where  its  knolls  and  hills  are  20  to  50  feet  high,  with  abundant  bowlders. 
The  same  northwestward  course  is  continued  tlirough  Ransom  County, 
passing  by  Lisbon  as  a  belt  of  knolls  and  hillocks  crowning  the  southwest 
bluff  of  the  Sheyenne  Valley,  to  the  conspicuous  morainic  hills  (including 
"Bears  Den  Hillock")  in  the  vicinity  of  Fort  Riansom,  rising  50  to  100 feet 
above  the  general  level  and  250  to  300  feet  above  the  river. 

At  the  time  of  accumulation  of  these  hills  the  ice-sheet  had  retreated 
a  few  miles  north  from  the  Head  of  the  Coteau  des  Prairies  and  10  to  25 
miles  eastward  from  the  moraine  referred  to  the  Kiester,  Elysian,  and 
Waconia  stages,  near  Straubville  and  Nicholson  and  along  Bear  Creek. 
The  northeastwardly  sloping  surface  of  the  greater  part  of  Sargent 
County  was  covered  by  a  glacial  lake,  whose  silt  beds,  confluent  south- 
west^vard  with  those  of  Lake  Dakota,  are  about  1,300  feet  above  the  sea 
from  Sargent  and  Straubville  southward  into  South  Dakota,  to  Newark, 
Kidder,  and  Burch,  but  decline  eastward  to  about  1,250  feet  on  the  south 
side  of  Silver  and  Sprague  lakes.  The  surface  of  this  glacial  lake  was 
1,300  feet,  or  probably  at  first  1,310  feet,  above  the  present  sea-level,  its 
outflow  being  southwestward  across  the  bed  of  Lake  Dakota  to  the  James 
River.  The  channel  of  this  outlet  is  doubtless  distinctly  traceable.  On 
the  north  this  lake  received  a  large  inflowing  stream,  the  representative  of 
the  present  Sheyenne  River,  which  brought  the  waters  that  were  discharged 
from  the  border  of  the  receding  ice-sheet  and  from  the  drainage  of  a  con- 
siderable belt  of  the  adjoining  land  along  all  the  distance  northward  to  the 
vicinity  of  Devils  Lake  and  thence  northwestward  to  the  head  of  the  Shey- 


THE  SEVENTH  OE  DOVEE  MORAINE.  149 

eniie.  Even  farther  northwest,  the  glacial  Lake  Souris  outflowed  by  this 
stream,  as  previously  at  its  beginning  it  had  found  outlet  during  the  time 
of  the  Elysian  and  Waconia  moraines  into  the  upper  part  of  the  James 
River,  flowing  through  Arrow  Wood  and  Jim  lakes  to  Lake  Dakota,  so 
long  as  that  lake  existed. 

This  great  affluent,  which  may  be  called  the  glacial  Sheyenne  River, 
is  marked  b»y  a  flat  or  in  part  moderately  undulating  belt  of  stratified 
gravel  and  sand,  extending  from  the  central  part  of  the  Fort  Ransom 
military  reservation  southward  by  Marshall  and  Nicholson.  It  includes  a 
width  of  1^  miles  to  the  west  and  an  equal  distance  to  the  east  of  Mar- 
shall, where  it  is  bounded  on  each  side  by  higher  tracts  of  smooth  till.  Its 
height  above  the  sea  at  Marshall  is  1,343  feet,  and  at  Nicholson,  where  it 
widens  into  the  glacial  lake  of  Sargent  County,  1,309  feet.  Two  compar- 
atively small  channels,  probably  occupied  by  the  stream  in  winter*  when 
glacial  melting  was  at  its  minimum,  were  seen  near  the  west  side,  on  the 
wide  alluvial  belt,  about  1 J  miles  and  1  mile  west  of  Marshall,  each  having 
a  width  of  an  eighth  of  a  mile  and  a  depth  of  about  15  feet.  One  of  these 
channels,  or  the  two  interlocking  and  here  and  there  separated  by  islands, 
is  commonly  known  as  the  Big  Slough,  and  has  an  extent  of  many  miles 
from  north  to  south. 

During  the  recession  of  the  ice  from  the  compound  moraine  on  the 
west  line  of  Sargent  and  Ransom  counties  to  the  Dovre  moraine,  before 
described,  the  glacial  lake  grew  as  fast  as  the  land  became  uncovered, 
extending  gradually  east  around  the  northern  base  of  the  Coteau  des 
Prairies  to  Skunk  Lake  (recently  called  Lake  Tewaukon),  northeast  over 
the  smoothly  undulating  surface  of  till,  very  abundantly  sprinkled  with 
bowlders,  about  Forman  and  Lake  Kandiota,  to  the  Stormy  Lakes  and 
adjacent  moraine  near  Milnor,  and  northward  along  the  moraine  and  ice 
front  into  Ransom  County.  Its  depth  at  Forman  was  50  feet;  at  Peny, 
6  miles  east,  nearly  100  feet;  and  farther  east  and  northeast,  beside  the 
Dovre  moraine,  about  150  feet,  if  it  continued  tributary  to  the  James 
River  through  the  whole  time  of  this  glacial  retreat. 

It  is  more  probable,  however,  that  when  the  recession  of  the  ice  vmcov- 
ered  Lake  Tewaukon  and  the  country  eastward,  an  outlet  was  found  in 


150  THE  GLACIAL  LAKE  AGASSIZ. 

that  direction  along  the  front  of  the  ice-sheet  and  the  Dovre  moraine, 
flowing-  into  Lake  Agassiz  in  the  northwest  part  of  township  129,  range  49. 
The  belt  of  stratified  gravel  and  sand,  1  to  2  miles  wide,  which  there  and 
for  a  distance  of  15  miles  southeastward  constitutes  the  border  of  this 
lacustrine  area,^  seems  to  have  been  deposited  by  this  great  river,  while 
the  ice-sheet  lay  on  its  northeast  side,  terminating  where-  the  edge  of  this 
level  or  somewhat  undulating  tract  descends  like  a  terrace  and  is  bordered 
by  the  slightly  lower  Herman  and  Norcross  beaches.  Since  the  deposition 
of  these  stratified  beds,  the  River  Warren,  outflowing  from  Lake  Agassiz, 
has  eroded  and  carried  away  their  continuation  across  an  extent  of  several 
miles  southeast  to  a  remnant  of  the  same  gravel  and  sand  which,  with 
underlying  till,  forms  the  plateau  cut  by  the  Fargo  and  Southern  (Chicago, 
Milwaukee  and  St.  Paul)  Railway  in  the  southeast  part  of  township  128, 
range  47,  Traverse  County,  Minn.,  ab.out  half  way  between  White  Rock 
and  Wheaton.  The  outline  of  the  ice  margin  along  the  extreme  south- 
western edge  of  this  glacial  lake  at  the  time  of  its  accumulating  the  Dovre 
moraine  and  forming  the  northeast  bank  of  the  glacial  Sheyenne  River  at 
its  entrance  to  the  area  of  Lake  Agassiz  may  therefore  be  somewhat  confi- 
dently traced  around  the  little  plateau  between  the  Bois  des  Sioux  and 
Mustinka  rivers  and  southward  by  Wheaton  to  the  rolling  land  about  the 
Tokua  Lakes  at  Grraceville.  The  prominent  morainic  hills  west  of  Taylor 
Lake,  according  to  this  interpretation  of  our  observations,  were  massed  in 
an  angle  of  the  ice  margin,  the  usual  place  for  plentiful  drift  accumulations. 
Windy  or  Airy  Mound,  on  the  northern  end  or  Head  of  the  Coteau 
des  Prairies,  close  south  of  the  line  between  North  and  South  Dakota,  is  a 
slight  elevation  above  the  general  surface  of  this  drift-covered  Cretaceous 
ridge.  Its  height  is  about  1,950  feet  above  the  sea,  and  by  estimate  100 
feet  lower  than  the  crest  of  this  ridge  a  few  miles  farther  south.  Thence 
gentle  slopes  descend  750  feet  to  Sprague  and  Skunk  lakes,  near  the  north- 
em  base  of  this  highland;  and  the  whole  view  east,  north,  and  west  from 
Windy  Mound  sweeps  over  a  broad,  nearly  flat  expanse  of  till  and  la,cus- 
trine  silt,  ranging  in  altitude  from  960  feet  at  Wahpeton  to  1,250  feet  at 
Forman  and  1,300  feet  on  the  area  of  Lake  Dakota  adjoining  the  James 

'  U.  S.  Geol.  Survey,  Bulletin  No.  39,  pp.  38-10. 


THE  SEVENTH  OR  DOVRE  MORAINE.  151 

River.  After  extending  as  a  continuous  massive  ridge  nearly  200  miles 
from  south-southeast  to  north-northwest  through  southwestern  Minnesota 
and  the  northeast  corner  of  South  Dakota,  with  an  elevation  increasing 
northward  from  1,600  to  2,050  feet  above  the  sea,  the  Coteau  des  Prairies 
is  thus  terminated,  and  along  the  next  175  miles  northward  to  the  south 
end  of  the  Pembina  Mountain  escarpment  no  conspicuous  rise  of  the  sur- 
face is  observable  from  a  great  distance  on  the  west  side  of  Lake  Agassiz 
and  the  flat,  low  plain  of  the  Red  River  Valley.  There  is,  however,  a 
slow  ascent  of  several  hundi'ed  feet  from  this  lacustrine  area  west  to  the 
plain-like  expanse  of  Cretaceous  shales  and  overlying  drift,  which  rises 
northward  from  1,200  to  1,300  feet  above  the  sea  in  Sargent  County  to 
about  1,500  feet  in  the  region  surrounding  Devils  Lake. 

Into  thi.'S  plain  the  Sheyenne  and  James  rivers  have  cut  narrow  and 
trough-like  channels  or  valleys  that  vary  from  a  third  or  a  half  of  a  mile 
to  commonly  1  mile  and  rarely  2  miles  in  width.  These  channels,  like  the 
narrow  morainic  belts  of  knolls  and  low  hills,  are  thus  minor  features  of 
the  general  topography.  The  Sheyenne  channel  or  valley  is  100  to  200 
feet  deep,  mainly  cut  in  the  Cretaceous  shales  for  its  lower  half  or  more, 
though  the  faces  of  the  bluffs  are  usually  covered  by  a  talus  of  drift,  while 
the  James  Valley,  ranging  from  75  to  125  feet  in  depth,  is  mostly  eroded 
in  the  drift  sheet,  there  thicker  than  along  the  Sheyenne.  From  the  vicin- 
ity of  Valley  City  northward  by  Cooperstown  to  De'sdls  Lake,  Langdon, 
and  a  large  part  of  southwestern  Manitoba,  stretching  west  from  the  crest 
of  the  Pembina  Mountain,  the  depth  of  the  drift  is  only  from  10  to  50  feet. 
Over  extensive  tracts  of  Griggs  and  Cavalier  counties  it  varies  from  10  to 
30  feet.  Its  average  northward  on  this  belt  is  small,  not  probably  more 
than  as  1  to  4  or  6  in  comparison  with  its  thickness  in  the  Red  River 
Valley,  throughout  western  and  southwestern  Minnesota  and  on  most  parts 
of  the  great  Cretaceous  ridge  of  the  Coteau  des  Prairies. 

Between  the  Dovre  moraine  and  the  compound  moraine  next  west  the 
general  level  of  the  northwestern  part  of  Sargent  County  and  of  south- 
western Ransom  County  is  diversified  by  three  massive  swells  or  hills,  which, 
like  the  surrounding  nearly  flat  country,  have  a  smooth  surface  of  till. 
One  of  these,  rising  75  to  100  feet  and  extending  2  or  3  miles  from  south 


152  THE  GLACIAL  LAKE  AGASSIZ. 

to  north,  is  in  the  west  part  of  township  131,  range  57,  close  west  of  Har- 
lem. Another,  also  ti'ending  with  the  meridian,  lies  12  to  15  miles  farther 
north,  between  Marshall  and  Elliott,  above  which  railway  stations  it  rises 
about  60  feet.  The  third  is  White  Stone  Hill,  which  extends  about  4  miles 
from  east  to  west  in  the  north  part  of  township  132,  range  56,  having  a 
somewhat  crescentric  and  oval  form,  convex  to  the  south,  with  a  height  of 
about  150  feet.  None  of  these  elevations  consists  of  morainic  drift,  but 
they  seem  to  be  due  to  the  prominence  of  the  underlying  shale,  which, 
however,  has  no  outcrops,  the  thickness  and  character  of  the  drift  being 
nearly  the  same  as  on  the  suiTouuding  intermorainic  area. 

Multitudes  of  bowlders,  mostly  Archean  gneiss  and  granite,  seldom 
exceeding  3  feet  in  diameter,  are  scattered  on  the  gently  undulating  expanse 
of  till  north  of  the  Head  of  the  Coteau.  The  bowlder-strewn  tract  extends 
west  to  Belle  Plaine  and  2  or  3  miles  west  of  Forman,  and  northward 
through  townships  130  and  131,  in  ranges  54  and  55,  occuppng  an  area 
of  about  150  square  miles.  The  bowlders  are  fully  fifty  times  more  plen- 
tiful than  their  average  numbers  on  similarly  smooth  areas  of  till  in  western 
Minnesota  and  North  Dakota,  their  proportion  being  nearly  the  same  as  on 
the  morainic  belts  of  this  region.  They  may  belong  to  morainic  drift 
which  has  been  smoothed  by  a  subsequent  advance  of  the  ice  over  it,  hav- 
ing been,  perhaps,  deposited  during  the  time  of  the  Kiester  or  Elysiau 
moraines,  and  covered  by  a  glacial  advance  at  the  time  of  the  Waconia 
moraine;  or  they  may  have  been  gathered  in  unusual  numbers  in  the 
englacial  drift  of  this  part  of  the  ice-sheet,  because  of  convergent  currents 
from  the  east  and  west,  together  with  the  influence  of  the  liighland  so  near 
on  the  south.  Further  observations  seem  needed  for  determining  satisfac- 
toril}^  the  reasons  for  their  abundance.  They  lie  upon  the  central  and 
eastern  part  of  the  lacustrine  area  of  Sargent  County,  unless  that  lake 
became  almost  wholly  drained  away  eastward,  as  is  probable,  before  this 
surface  was  uncovered  from  the  ice. 

The  Dovi-e  moraine  extends  north  from  its  high  hills  in  the  Fort  Ran- 
som Reservation  and  forms  a  belt  of  lower  rolling  and  knoUy  till,  with 
plentiful  bowlders,  thi-ough  sections  34,  27,  and  22,  township  136,  range 
58.     On  each  side  it  is  bounded  bv  flat  tracts,  about  50  feet  lower  than  the 


THE  SEVENTH  OR  DOVRE  MORAINE.  153 

highest  points  of  the  moraine  and  200  feet  above  the  Sheyenne,  that  on 
the  west  being  till  and  that  on  the  east  stratified  gravel  and  sand  1  to  2 
miles  wide,  dividing  the  moraine  from  the  trough-like  Sheyenne  channel  or 
valley.  From  near  the  center  of  this  township  the  morainic  belt,  contin- 
uing with  inconspicuous  development,  passes  northeastward  across  the 
Sheyenne,  and  at  the  northeast  corner  of  this  township  and  in  section  6  of 
that  next  east  the  drift,  heaped  in  a  reentrant  angle  of  the  ice  border,  forms 
Standing  Rock  Hill,  rising  100  feet  above  the  general  level  and  about  300 
feet  above  the  river.  Thence  this  moraine  turns  back  by  a  right  angle  to 
the  west  and  northwest,  recrossing  the  Sheyenne  and  rising  in  hills  50 
to  100  feet  high,  through  sections  34,  27,  28,  21,  20,  and  17,  township  137, 
range  58,  approaching  within  a  mile  of  the  equally  prominent  hills  of  the 
Waconia  moraine  at  its  reentrant  angle  in  the  next  township  on  the  west. 

Continuing  thence  to  the  north,  the  Dovre  moraine  is  represented  by  a 
narrow  series  of  knolls,  20  to  30  or  40  feet  above  the  general  level,  through 
township  138,  range  58,  veering  slightly  to  the  east,  and  closely  skirting 
the  west  side  of  the  Sheyemie  Valley  across  the  northern  half  of  the  town- 
ship. Its  di-ift  covers  the  east  slope  and  top,  and  its  bowlders  are  strewn 
abundantly  on.the  west  slope  of  a  hill  of  the  Fort  Pierre  shale  which  rises 
nearly  on  the  line  between  sections  32  and  33,  township  139,  range  58,  to  a 
height  50  feet  above  the  average  of  the  adjoining  country,  or  about  225  feet 
above  the  river.  Thence  the  moraine  appears  to  turn  northeastward  and 
to  lie  concealed  across  a  distance  of  about  4  miles  beneath  the  hiffh  flood- 
plain  of  gravel  and  sand  adjoining  the  Sheyenne,  out  of  which  the  apex  of 
a  sharply  reentrant  angle  projects  in  two  typically  morainic  hills  about  40 
feet  high  in  or  near  section  12  of  this  township,  some  2  miles  east  of  the 
river.  Returning  thence  west-southwestward  to  the  prominent  and  massive 
hill  in  the  north  part  of  section  19  of  this  township  139,  range  68,  2  miles 
west  of  the  river,  abundant  bowlders,  apparently  marking  the  course  of  the 
ice  front  at  the  time  of  the  Dovre  moraine,  are  strewn  over  the  east,  north- 
east, and  southwest  sides  of  this  hill,  which,  however,  is  principall}-  a 
rounded  projection  or  boss  of  the  Fort  Pierre  shale,  seen  in  the  slight 
ravines  of  its  east  side  to  40  feet  below  its  top.  The  higher  part  of  its 
southwesterly  sloping  but   somewhat    plateau-like    top,  less    encumbered 


154  THE  GLACIAL  LAKE  AGASSIZ. 

with  bowlders  than  its  sides,  is  about  125  feet  above  the  general  level, 
or  300  feet  above  the  Sheyenne.  In  the  view  from  this  hill  I  traced 
faint  indications  of  the  course  of  the  Do\Te  moraine  in  a  curve  passing 
northwest,  north,  and  northeast  to  the  similarly  prominent  hill  2  miles 
west-northwest  of  Valley  City.  The  highest  hills  of  the  moraine  in  this 
distance  of  7  miles  rise  about  60  feet  above  the  general  level  in  sections  11 
and  2,  township  139,  range  59.  All  the  sui'face  from  this  loop  eastward  3 
or  4  miles  to  the  Sheyenne  Valley  is  a  very  smooth,  fertile  tract,  apparently 
the  flood-plain  of  the  river  when  it  flowed  about  1 75  feet  above  its  present 
level,  at  the  time  of  the  retreat  of  the  ice-sheet  from  this  moraine. 

In  section  18,  township  140,  range  58,  IJ  miles  north  of  the  Northern 
Pacific  Railroad  and  slightly  farther  northwest  of  Valley  City,  a  prominent 
tract  of  morainic  drift,  probably  owing  part  of  its  height  to  an  underlying 
hummock  of  the  Cretaceous  shale,  rises  100  feet  above  the  old  gravel  and 
sand  flood-plain  of  the  Sheyenne  on  the  east  or  about  300  feet  above  the 
river.  The  surface  of  this  elevation  is  abundantly  strewn  with  bowlders 
and  is  very  irregularly  broken  by  ravines,  hillocks,  and  small  ridges,  trend- 
ing from  south  to  north  to  its  highest  point  and  thence  trending  toward  the 
west-northwest,  indicating  that  there  was  here  another  reentrant  angle 
of  the  ice  margin.  Looking  across  the  country  west-northwestward,  I  ob- 
served low  knolls  and  ridges  of  this  moraine,  scarcely  above  the  general 
level,  extending  at  least  2  or  3  miles;  but  no  prominent  hills  are  visible  in 
this  direction.  Two  to  3  miles  north  of  Hobart  this  moraine  curves  north- 
ward, and  passes  as  a  narrow  belt  of  knolly  drift  north  and  northeast  through 
the  east  half  of  township  141,  range  59,  and  across  the  Slieyemie  to  the 
northeast  part  of  township  142,  range  58,  where  it  becomes  partially  merged 
with  the  Fergus  Falls  moraine.  Thence  turning  back  by  a  right  angle,  it 
recrosses  the  Sheyenne  about  a  mile  above  the  mouth  of  Bald  Hill  Creek 
and  extends  northwestward  along  the  east  side  of  this  creek.  Its  most 
prominent  portion,  called  Bald  Hill,  lies  5  miles  east  of  Dazey  and  extends 
along  a  distance  of  2  miles  or  more  from  southeast  to  northwest,  rising  some 
300  feet  above  the  Sheyenne  or  fully  100  feet  above  the  general  level. 

Tlu-ough  Griggs  County  the  Dovre  moraine  is  very  well  developed 
and  forms  especially  conspicuous  hills  west  and  north  of   Cooperstown, 


THE  SEVENTH  OE  DOVRE  MORAINE.  155 

rising  75  to  160  feet  above  the  adjoining  country.  From  Bald  Hill  it 
take.s  a  very  straight  course  a  little  west  of  north  for  15  miles  to  the  center 
of  township  146,  range  59,  2  to  3  miles  west  of  Cooperstown,  having 
through  this  distance  an  average  width  of  a  mile  and  consisting  of  many 
knolls  and  small  hills  of  till,  with  abundant  bowlders,  rising  25  to  50  feet 
above  the  nearly  level  surface  on  each  side.  Toward  the  west  this  belt  is 
bordered  along  much  of  its  extent  by  an  overwashed  plain  of  gravel  and 
sand,  about  a  mile  wide,  descending  by  a  very  gentle  slope  away  from 
the  moraine,  which  thus  has  a  very  definite  boundary;  but  on  the  east 
there  is  a  gradual  change  through  a  decreasingly  knolly  and  rolling  con- 
tour to  the  slightly  undulating  expanse  of  intermorainic  till,  with  only  few 
bowlders,  which  stretches  4  to  6  miles  east  to  the  Sheyenne  Valley  and  20 
miles  north  between  the  moraine  and  the  Sheyenne,  from  Bald  Hill  to  the 
scattered  hills  of  a  reentrant  angle  of  this  Dovre  moraine  4  to  6  miles  north 
of  Cooperstown. 

About  5  miles  farther  north  another  angle  of  the  moraine  is  marked 
by  the  conspicuous  hill  called  Butte  Mashue,  from  the  name  of  an  Indian 
Avho  was  buried  in  a  mound  on  its  summit.  This  hill,  situated  in  the  east 
half  of  section  35,  township  148,  range  59,  rises  150  or  175  feet  above  the 
general  level  east  and  north,  or  nearly  350  feet  above  the  Sheyenne  River, 
which  is  only  1  mile  distant  at  the  northeast.  It  is  a  typical  morainic  drift 
hill  of  small  area,  irregularly  knolly  contour,  and  very  abundant  bowlders. 
Its  diameter  of  base  is  only  a  third  to  a  half  of  a  mile.  On  the  township 
line  south  of  this  section  35  there  is  a  hollow  a  quarter  of  a  mile  wide, 
through  which  a  road  runs  from  east  to  west,  nearly  150  feet  below  the  top 
of  the  Butte  Mashue.  Iimaiediately  to  the  south,  in  the  north  edge  of  sec- 
tion 2,  a  very  rocky  and  typically  morainic  north-to-south  ridge  rises  about 
125  feet;  and  thense  a  series  of  hills  and  short  morainic  ridges,  75  to  125 
feet  high,  extends  south  to  the  irregularly  scattered  hills  of  similar  heights 
which  occupy  most  of  the  area  between  Cooperstown  a-nd  Clear  Lake. 

Unusual  numbers  of  limestone  bowlders  were  observed  in  this  vicinity 
on  the  morainic  hills  and  adjacent  to  them,  including  many  6  to  8  feet  in 
diameter,  one  mass  10  by  15  feet  in  dimensions,  and  another,  seen  close 
east  of  the  south-to-north  road  about  a  mile  south  of  the  Butte  Mashue, 


156  THE  GLACIAL  LAKE  AGASSIZ. 

measuring  20  by  30  feet  and  projecting  1  to  2  feet  above  the  surface,  and 
shown  by  digging  to  be  more  than  3  feet  thick.  All  these  are  grayish- 
yellow,  very  compact  magnesian  limestone,  similar  to  that  which  is  found 
forming  bowlders  of  equal  abundance  near  Audubon  and  the  White  Earth 
Agency  in  Becker  County,  Minn.,  and  again  on  the  massive  morainic  hills 
near  Fort  Totten,  on  the  south  side  of  Devils  Lake.  In  these  localities 
the  limestone  bowlders  sometimes  occur  in  equal  or  even  greater  numljers 
than  those  of  the  Ai'chean  rocks;  but  generally  tlu-oughout  this  region  the 
proportion  of  such  limestone  masses  in  the  drift  is  verj^  small,  averaging 
probably  not  more  than  a  hundredth  part  of  the  large  bowlders,  though  the 
portions  of  the  gravel  of  the  drift  supplied  respectively  by  the  limestone 
and  the  Archean  rocks  are  commonly  about  equal.  They  are  like  the  out- 
crops of  magnesian  limestone  in  the  neighborhood  of  Winnipeg,  in  Mani- 
toba, 165  to  180  miles  distant  to  the  north,  which  are  its  nearest  natural 
exposures. 

West  of  Butte  Mashue.  the  Dovre  moraine  is  represented  by  knolls 
and  hills  25  to  75  feet  high,  which  continue  to  the  prominently  rolling 
land  surrounding  Norway  Lake,  in  the  northeast  corner  of  township  147, 
range  60.  Next  this  moraine  extends  northward  in  an  inconspicuous  belt 
of  knolly  and  rolling  till  to  low  hills  in  or  near  section  23,  township  149, 
range  60 ;  and  thence,  turning  to  the  west-northwest,  it  holds  this  general 
course  through  a  distance  of  30  miles  to  the  Devils  Heart  Hill.  It  crosses 
the  Sheyenne  River  in  the  southeast  part  of  township  150,  range  61,  and 
forms  a  conspicuous  belt  of  hills,  100  to  150  feet  high,  along  the  south  side 
of  township  151,  range  63,  4  to  5  miles  south  of  Free  Peoples  Lake.  A 
lower  but  well-marked  series  of  morainic  hills  and  knolls,  mostly  40  to  60 
feet  high,  with  very  abundant  bowlders,  curves  thence  northwest  and  north, 
passing  through  the  center  of  township  151,  range  64,  to  the  Devils  Heai-t. 
Again,  only  a  few  rods  north  of  the  base  of  that  hill,  a  typically  iiTegular 
belt  of  very  rocky  morainic  knolls,  30  to  50  feet  high,  occupying  a  width 
of  only  20  or  30  rods,  trends  from  east-southeast  to  west-northwest,  and 
forms  the  frontal  line  of  the  chief  morainic  tract  bordering  the  south  side 
of  Devils  Lake  (PI.  XVIII).  The  Dovre  moraine  south  of  the  Devils 
Heart  Hill  would  thus  join  a  larger  morainic  tract  on  the  north,  which 


DEVILS  HEART  HILL.  157 

appears  referable  to  the  Fergus  Falls  and  Leaf  Hills  moraines.  At  this 
intersection  there  is  heaped  the  largest  and  most  remarkable  kame  that  has 
ever  come  under  my  observation,  known  by  its  aboriginal  appellation  as 
the  Devils  Heart.  This  mound  of  gravel  and  sand  appears  to  have  been 
deposited  where  a  glacial  river  descended  from  the  convergent  slopes  of 
the  ice-sheet  to  the  open  land  contemporaneously  with  the  accumulation 
of  the  Dovre  moraine. 

Devils  Heart  Hill  rises  in  steep  slopes  of  20°  to  30°,  being  thus  steep 
on  all  sides  excepting  the  south,  where  the  otherwise  nearly  round-topped, 
conical  hill  is  somewhat  drawn  out  into  a  naiTOw,  more  slowly  descending 
ridge;  It  consists  of  gravel  and  sand,  mostly  not  showing  pebbles  on  the 
surface  larger  than  IJ  inches  in  diameter.  A  few  bowlders,  however,  a 
score  or  more  in  all,  are  seen  on  the  sides  of  this  hill  to  its  top,  and  one 
a  foot  long  (the  only  one  seen  at  the  crest)  is  embedded  in  the  gravel  a 
rod  south  of  the  highest  point  and  less  than  1  foot  lower.  The  gravel  is 
of  threefold  origin,  being  derived  in  about  equal  proportions  from  granitic 
and  gneissic  Archean  rocks,  from  the  Silurian  limestones,  and  from  the 
Cretaceous  shales.  Nearly  all  of  the.  bowlders  seen  on  the  hill  are  granite 
or  gneiss,  but  two  or  three  on  its  west  side  are  limestone.  It  is  situated  in 
section  4,  township  151,  range  64,  about  a  mile  southwest  from  the  head  of 
Donahues  Bay  of  Devils  Lake.  Its  height  above  its  base  is  about  175 
feet,  and  above  Devils  Lake,  according  to  Nicollet's  barometric  determina- 
tion, 290  feet,  which  appears  to  be  about  15  feet  higher  than  Sullys  Hill, 
the  culminating  point  of  the  very  prominent  hills  of  morainic  till  south  of 
Devils  Lake.  From  the  altitude  of  the  lake,  1,430  to  1,484  feet  above  the 
sea,  as  known  by  railway  siu-veys,  the  top  of  the  Devils  Heart  is  approx- 
imately 1,722  feet,  and  of  Sullys  Hill,  1,707  feet,  above  the  sea. 

The  Dovre  moraine  is  blended  with  the  later  Fergus  Falls  and  Leaf 
Hills  moraines  from  the  Devils  Heart  northwest  and  west  by  Fort  Totten 
and  the  Crow  Hills  to  the  northwest  part  of  township  151,  range  66,  in  the 
west  edge  of  the  Indian  reservation,  where  it  again  becomes  a  separate  belt. 
Thence  it  passes  in  a  general  west-northwestward  course  along  the  north 
side  of  the  Antelope  Valley  to  the  area  of  the  glacial  Lake  Souris.  Imme- 
diately north  of  Oberon  its  Yevy  irregular  knolls,  hills,  and  small   short 


158  THE  GLACIAL  LAKE  AGASSIZ. 

ridges  border  the  Minnewaukan  branch  of  the  Northern  Pacific  Raihoad 
along  a  distance  of  3  miles.  Next  to  the  north  there  is  a  width  of  nearly 
2  miles  of  moderately  undulating,  smooth  till,  in  the  central  part  of  which 
is  the  disused  Fort  Totten  station.  Westward  this  smooth  tract  extends 
about  2  miles,  dividing  the  Dovre  moraine  on  the  south  from  the  compound 
Fergus  Falls  and  Leaf  Hills  moraines  on  the  north ;  but  beyond  this  it  is 
interrupted  by  morainic  hills  surrounding  Long  Lake,  where  the  two  belts 
seem  to  be  once  more  united.  The  further  course  of  the  Do^Te  moraine 
and  its  relationship  with  these  later  moraines  upon  the  very  scantily  settled 
country  extending  from  Long  Lake  and  Minnewaukan  westward  have  not 
been  definitely  traced  and  are  laid  down  on  the  map  (PI.  XVII)  only 
in  a  provisional  manner.  It  is  probable  that  the  Dovre  moraine  is  well 
developed  5  to  10  miles  south  of  Rugby  Junction,  where  the  surface  bears 
numerous  small  lakes,  and  that  it  is  also  represented  on  the  southeast  part 
of  the  Lake  Souris  area  by  swells  about  60  feet  above  the  general  level, 
seen  1  to  3  miles  southeast  of  Berwick.  The  continuation  of  the  ice  border 
thence  northwest  may  have  been  apjDroximately  coincident  with  the  sand 
hills  lying  on  both  sides  of  the  Souris  or  Mouse  River,  in  townships  157 
and  158,  ranges  75  and  76.  Little  Medicine  Lodge,  so  named  from  its 
being  formerly  the  scene  of  dances  of  the  Indians,  with  incantations  of 
their  medicine  men,  is  one  of  these  dunes  without  vegetation,  which  rises 
about  75  feet  in  height  on  the  west  bank  of  the  Souris  River,  5  miles  north 
of  Towner. 

EIGHTH   OR  FERGUS   FALLS  MORAINE. 

The  eighth  and  ninth  or  Fergus  Falls  and  Leaf  Hills  moraines  unite 
in  the  south  part  of  Ottertail  County,  Minn.,  to  form  the  Leaf  Hills,  100 
to  350  feet  high,  which  reach  from  Fergus  Falls  in  a  semicircle  50  miles 
southeast,  east,  and  northeast,  to  the  Leaf  Lakes.  These  are  the  most  con- 
spicuous morainic  hills  of  this  State ;  and  on  accoimt  of  their  prominence 
above  all  the  adjoining  country  they  have  been  commonly  called  the  Leaf 
Mountains.  Eastward  from  these  hills  the  Fergus  Falls  moraine  seems 
to  be  merged  with  the  Dovre  moraine  tln-ough  Miltona  and  Spruce  Hill, 
in  the  northeast  part  of  Douglas  County,  and  through  southwestern  and 
southern  Todd  County.      Next  it  runs  northward  in  a  well-marked  belt 


THE  EIGHTH  OR  FERGUS  FALLS  MORAINE.  159 

of  di-ift  hills  through  the  east  edge  of  Todd  County  to  the  magnificent 
development  of  this  moraine,  apparently  united  again  with  the  ninth  or 
Leaf  Hills  moraine,  about  Fish  Trap  Lake  and  Lake  Alexander,  in  north- 
western Morrison  County.  Crossing  to  the  east  side  of  the  Mississippi,  the 
Fergus  Falls  moraine  passes  south  along  the  east  side  of  this  river's  Glacial 
flood-plain  to  Hole-in-the-Days  Bluff  and  the  massive  hills  east  of  Little 
Falls,  where  it  is  probably  combined  with  a  reentrant  angle  of  the  Dovre 
moraine.  Thence  it  passes  northeastward  through  the  southeast  part  of 
Crow  Wing  County,  skirting  the  northwest  side  of  Mille  Lacs ;  and  curv- 
ing next  southeastward  around  this  lake,  it  appears  to  be  represented  by 
morainic  hills  observed  in  the  southeast  part  of  Aitkin  County  and  in 
northwestern  Pine  County.  Northward  from  Fergus  Falls,  this  moraine 
passes  by  Lakes  Lida  and  Lizzie  to  Detroit,  the  White  Earth  Agency,  and 
White  Earth  Lake ;  and  thence  it  turns  nearly  by  a  right  angle  west-north- 
west to  the  Frenchmans  Bluff,  in  township  143,  range  43,  Norman  County, 
west  of  which  it  enters  the  area  of  Lake  Agassiz,  close  south  of  the  Wild 
Rice  River.  ^ 

The  course  of  the  ice  front  where  it  formed  the  northern  barrier  of 
Lake  Agassiz  at  the  time  of  its  accumulation  of  the  eighth  or  Fergus  Falls 
moraine  is  marked  by  hilly  and  knoUy  di-ift  deposits,  with  plentiful  bowl- 
ders, both  east  and  west  of  the  lake  near  the  latitude  of  47°  10',  which 
passes  20  miles  north  of  Fargo;  by  an  unusual  abundance  of  bowlders 
near  this  latitude  and  farther  north  on  portions  of  the  slightly  undulating 
or  nearly  level  till  forming  each  side  of  the  lacustrine  area;  and  by  a  tract 
of  till  several  miles  in  width,  probably  representing  both  the  eighth  and 
ninth  or  Fergus  Falls  and  Leaf  Hills  moraines  combined,  which  stretches 
across  the  Red  River  Valley  at  Caledonia,  from  Ada,  Rolette,  and  Beltrami 
west  to  Reynolds,  Buxton,  Cummings,  and  Blanchard,  constituting  the  bed 
and  banks  of  the  river  along  the  Groose  Rapids.  In  Lake  Agassiz  the 
morainic  till  was  spread  with  a  generally  even  surface,  but  it  has  many 
small  inequalities,  the  higher  portions  being  3  to  5  feet  or  rarely  10  feet 
above  adjoining  hollows.     Bowlders  and  gravel  are  plentiful  on  its  surface, 

•Geology  of  Minnesota,  Vol.  II,  pp.  630,  642;  625;  581-585,  605;  563,  564,  571;  475,  477,  478,  488; 
544-549  [Fergus  Falls  and  the  Leaf  Hills]  ;  647,  6.52.  U.  S.  Geol.  Survey,  Bulletin  No.  39,  p.  33.  (The 
references  are  in  geographic  order,  from  east  to  west.J 


160  THE  GLACIAL  LAKE  AGASSIZ. 

this  being  the  onl j  inteiTuptiou  of  the  lacustrine  and  alkivial  clayey  silt 
which  elsewhere  continuously  occupies  the  central  part  of  the  Red  River 
Valley  plain  from  near  Breckenridge  to  Winnipeg. 

In  North  Dakota  the  Fergus  Falls  moraine  passes  southward  in  a  loop 
outlining  a  lobe  of  the  ice-sheet  which  lay  between  Lake  Agassiz  and  the 
Sheyenne  River.  This  lobe  reached  about  40  miles  south  from  the  latitude 
of  Caledonia,  which  marks  approximately  the  apex  of  a  glacial  reentrant 
angle  in  the  Red  River  Valley,  where  the  laving  action  of  Lake  Agassiz 
appears  to  have  caused  the  melting  of  the  ice  border  to  progress  faster 
than  on  the  land  surface  at  each  side.  Emerging  from  the  lacustrine  area, 
on  which  its  drift  was  leveled  by  the  waves,  the  Fergus  Falls  moraine  pre- 
sents a  prominently  rolling  surface  of  till  west-southwest  of  Galesburg,  and 
forms  tyi^ical  morainic  hills  in  the  northwest  part  of  township  142,  range 

53,  1  to  3  miles  west  of  Erie,  rising  50  to  75  feet  above  the  intervening 
hollows  and  the  adjoining  surface  of  smoothly  undulating  till  westward, 
and  100  feet  or  more  above  the  highest  shore  of  Lake  Agassiz.  Thence 
the  east  boundary  of  the  ice-lobe  is  marked  by  rolling  and  knolly  till, 
with  plentiful  bowlders,  and  by  low  kames  of  gravel  and  sand,  occupying 
generally  a  belt  about  1  mile  wide,  which  runs  south-so  uthwestward  close 
north  and  west  of  Ayr  and  southward  across  the  Northern  Pacific  Railroad 
1  to  2  miles  east  of  Buffalo.     In  the  northwest  part  of  township  139,  range 

54,  a  few  miles  south  of  this  railroad,  this  morainic  belt,  continuing  with 
similar  features,  turns  to  the  west-southwest,  crosses  the  Maple  River,  and 
holds  this  course  about  a  dozen  miles,  passing  thi-ough  sections  25  to  28 
and  32  and  31,  township  139,  range  56.  This  portion  defines  the  southern 
extremity  of  the  ice-lobe,  the  distance  of  its  retreat  from  the  Dovre  moraine 
at  Taylor  Lake  and  near  Geneseo  and  Cayuga  having  been  about  55  miles. 
In  Minnesota  the  recession  of  the  ice  from  Dovre  to  the  Leaf  Hills  was  60 
miles,  and  along  the  Red  River  Valley  it  was  approximately  100  miles 
from  the  southeast  corner  of  North  Dakota  to  Caledonia. 

Occasional  kame  knolls  and  small  plateaus  of  gravel  and  sand,  15  to 
25  feet  high,  were  observed  along  a  distance  of  a  dozen  miles  south  of  the 
end  of  this  morainic  loop,  in  townships  138  and  137,  range  57,  showing 
where  glacial  streams  had  flowed  down  from  the  ice-sheet  dui'ing  Ls  retreat 


THE  EIGHTH  OE  FEEGUS  FALLS  MOEAINE.  161 

between  the  Dovre  and  Fergus  Falls  moraines,  and  there  are  small  areas- 
of  undulating  or  nearly  level  gravel  and  sand  associated  with  these  kames. 
With  these  exceptions,  all  the  expanse  there  and  southward  between  the 
Dovre  moraine  and  the  area  of  Lake  Agassiz  consists  of  smoothly  undu- 
lating intermorainio  till.  A  similar  sheet  of  till  also  occupies  the  area  15 
to  20  miles  wide  inclosed  on  the  north  between  the  sides  of  the  raorainic 
loop,  from  Tower  City  and  Oriska  to  Page  City,  Hope,  and  Sherbrooke. 

From  sections  36,  25,  and  26,  township  139,  range  57,  the  Fergus 
Falls  moraine  takes  a  north-northwest  course  through  section  14  in  this 
township,  there  and  onward  forming  morainic  hills  20  to  60  feet  high, 
strewn  with  abundant  bowlders,  to  the  Northern  Pacific  Railroad.  Alta 
station  (having  a  side  track  for  trains  to  pass  each  other,  but  no  depot)  is 
situated  near  the  middle  of  the  morainic  belt,  which  there  has  a  width  of 
about  2  miles,  consisting  of  very  irregular  drift  hills  25  to  75  feet  high, 
with  many  bowlders.  Thence  the  moraine  extends  nearly  due  north  about 
40  miles,  with  a  width  that  varies  from  1  to  3  miles,  lying  2  to  8  miles  east 
of  the  Sheyenne  River,  and  forming  the  watershed  between  the  Sheyenne 
and  the  Maple,  to  Pickert  post-office,  in  section  7,  township  146,  range  56, 
6  miles  west  of  Sherbrooke.  It  is  especially  well  developed  and  incloses 
several  lakelets  in  the  west  half  of  township  141,  range  57.  It  also  occu- 
pies almost  the  entire  west  half  of  the  next  township  northward,  and  in 
its  northwest  corner  is  interlocked  with  a  reentrant  angle  of  the  Dovi-e 
moraine.  Beyond  this  it  runs  slightly  to  the  east  of  north,  passing  with  a 
width  of  about  3  miles  through  the  middle  of  the  north  half  of  township 
143,  range  57,  and  onward  through  southwestern  Steele  County,  where  it 
lies  6  to  9  miles  west  of  Hope  and  Sherbrooke.  The  morainic  knolls  and 
hills  along  this  distance  rise  commonly  20  to  60  feet  above  the  smoothly 
undulating  till  on  each  side. 

Massive  hills  of  Cretaceous  shale,  overspread  with  a  smooth  surface  of 
till,  are  found  in  Barnes  County,  both  west  and  east  of  the  moraine,  5  to  10 
miles  north  of  Valley  City  and  Alta.  The  largest  of  these  hills  or  swells 
extends  nearly  4  miles  from  south  to  north  in  sections  32,  29,  20,  and  17, 
township  141,  range  58,  close  east  of  the  Sheyenne  River,  above  which  it 
rises  about  275  feet.  Its  height  above  the  Glacial  flood-plain  of  the  Shey- 
enne, a  nearly  level  tract  of  gravel  and  sand  on  the  east,  about  3  miles 
MON   XXV 11 


162  THE  GLACIAL  LAKE  AGASSIZ. 

wide,  is  by  estimate  76  feet.  Thence  this  plain  of  stratified  drift  extends 
south  along  the  east  side  of  the  Sheyenne  by  Valley  City  and  through 
township  139,  range  58,  varying  from  2  to  4  miles  in  width.  In  the  west 
half  of  section  25,  township  142,  range  58,  a  smaller  swell  or  hill  with  such 
smooth  surface  rises  to  nearly  the  same  height,  being  likewise  about  75  feet 
above  the  plain  of  valley  drift  on  the  southeast  and  south.  Against  the 
northeast  edge  of  this  smooth  hill,  the  nucleus  of  which  is  doubtless  Creta- 
ceous shale,  there  are  piled  typical  morainic  accumulations,  50  to  100  feet 
high,  whose  very  uneven  coutour  and  plentiful  bowlders  afford  a  remark- 
able contrast.  Another  Cretaceous  hill,  called  Pilot  Mound,  whose  surface, 
smoothly  oval  like  a  di'umlin,  shows  only  the  overlying  till,  rises  in  the 
southeast  quarter  of  section  2,  township  141,  range  57,  to  a  height  of  75  or 
100  feet  above  the  surrounding  smooth  expanse  of  till  on  all  sides.  The 
base  of  this  hill  is  about  a  third  of  a  mile  long  from  south  to  north,  and  its 
width  is  about  a  quarter  of  a  mile.  Its  sides  and  top  have  somewhat  more 
plentiful  bowlders  than  the  adjoining  country,  but  no  morainic  accumula- 
tions were  observed  nearer  than  the  Fergus  Falls  moraine,  which  lies  2 
miles  distant  to  the  west. 

In  the  northwest  part  of  Steele  County  the  Fergus  Falls  moraine 
turns  to  a  north-northwest  course,  which  it  holds  along  an  extent  of  about 
25  miles  to  the  southwest  part  of  township  150,  range  58,  in  Nelson 
County,  where  it  unites  with  the  ninth  or  Leaf  Hills  moraine.  In  the 
south  edge  of  Nelson  County  the  Fergus  Falls  moraine  has  a  width  of 
about  IJ  miles,  with  its  east  boundary  at  the  northeast  corner  of  section 
34,  3  miles  east  of  Lee  and  the  Sheyenne  River.  Its  small  knolls  and 
hillocks  jof  till,  with  abundant  bowlders,  there  rise  20  to  40  feet  above  the 
intervening  hollows  and  the  adjoining  surface,  which  is  moderately  undu- 
lating till,  with  few  bowlders,  having  a  height  of  175  to  200  feet  above  the 
Sheyenne. 

Beyond  township  150,  range  58,  the  Fergus  Falls  and  Leaf  Hills 
moraines  are  so  indistinguishably  combined  in  their  prominent  accumula- 
tions south  of  Stump  and  Devils  lakes,  on  the  Big  Butte,  and  northwest- 
ward by  Broken  Bone  Lake  to  the  Turtle  Mountain,  that  the  two  along  this 
extent  of  about  140  miles  will  be  best  considered  together  under  the  next 
division  of  this  subject. 


THE  LEAF  HILLS.  163 


NINTH  OR  LEAF   HILLS  MORAINE. 


West  of  the  Mississippi  the  Leaf  Hills  moraine  passes  through  east'^vn 
Cass  County  in  a  belt  of  knolly  and  hilly  till,  with  extensive  kame  deposits 
of  gravel  and  sand,  occupying  together  a  width  of  2  to  4  miles,  extending 
southwesterly  by  Crooked,  White  Fish,  Pelican,  Grull,  and  Sylvan  lakes,  to 
the  Crow  Wing  River  about  10  miles  west  of  Brainerd.  Crossing  to  the 
south  side  of  the  Crow  Wing,  it  is  merged  with  the  Fergus  Falls  moraine 
in  the  plexus  of  morainic  accumulations  suiTounding  Lake  Alexander  and 
Fish  Trap  Lake.  Thence  it  passes  west  through  the  northern  tier  of  town- 
ships in  Todd  County  to  the  Leaf  Lakes  in  Ottertail  County.^ 

The  Leaf  Hills,-  extending  southward  and  then  westward  from  the 
Leaf  Lakes,  through  East  Battle  Lake,  Folden,  Eflfington,  Leaf  Mountain, 
and  Eagle  Lake  townships,  are  the  combined  Fergus  Falls  and  Leaf  Hills 
moraines,  like  the  great  morainic  belt  south  of  Stump  and  Devils  lakes,  in 
North  Dakota.  Beyond  Eagle  Lake  the  Leaf  Hills  moraine  is  again 
separate,  passing  northwest  and  north  in  a  well-marked  belt,  1  to  3  miles 
wide,  of  knolls,  short  ridges,  and  low  hills  of  till,  with  abundant  bowlders, 
through  Tordenskjold,  Swerdrup,  Maine,  Star  Lake,  and  Edna  townships, 
amid  multitudes  of  lakes,  to  the  prominent  group  of  kames  about  5  miles 
northwest  of  Perham.  A  parallel  belt  of  low  morainic  hills  extends  north- 
northwestward  from  East  Leaf  Lake,  passing  a  few  miles  east  of  Rush 
Lake  to  the  south  end  and  east  side  of  Pine  Lake.^ 

In  Becker  County,  according  to  my  observations  in  1889,  these  mo- 
rainic belts  become  united  and  form  conspicuous  hills  of  till,  with  many 
bowlders,  denominated  the  Toad  Mountains,  which  rise  100  to  200  feet 
above  the  general  level  or  1,500  to  1,600  feet  above  the  sea.  Northward 
this  moraine  has  a  width  of  4  to  6  miles  in  low  hillocks,  little  ridges,  and 
knolls,  including  much  kame  gravel  and  sand,  in  its  course  by  Round, 
Many  Point,  and  Elbow  lakes,  and  the  extreme  source  of  the  Red  River. 
About  Rock  Island  Lake  and  east  of  the  Twin  Lakes,  in  townships  143 

1  Geology  of  Minnesota,  Vol.  II,  1888,  pp.  581-584,  606;  564,  571,  572. 

^Tlie  name  given  by  the  Ojibways  to  this  belt  of  hills  signifies  Rustling  Leaf  Mountain,  and  the 
same  name  is  by  them  also  extended  to  the  Leaf  Lakes  and  River  (Rev.  J.  A.  Gillillan,  in  the  Fifteenth 
Annual  Report,  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  for  1886,  p.  469). 

=  Geology  of  Minnesota,  Vol.  II,  pp.  546-549. 


164  THE  GLACIAL  LAKE  AGASSIZ. 

and  144,  range  39,  on  the  road  from  White  Earth  to  Red  Lake,  also  south 
of  Mountain  Lake,  and  at  the  east  side  of  the  Lower  Rice  Lake,  the  Leaf 
Hills  moraine  is  well  developed,  forming  hills  50  to  75  feet  and  occasion- 
ally 150  to  200  feet  or  more  in  height,  profusely  strewn  with  bowlders.  It 
continues  north  in  a  hilly  belt  several  miles  wide  through  range  39,  by  the 
sources  of  Poplar  and  Hill  rivers,  to  the  south  side  of  Lost  River,  in  the 
edge  of  the  Red  Lake  Indian  Reservation,  where  it  turns  shai-ply  westward 
on  the  southeastern  Herman  shore  of  Lake  Agassiz,  in  the  south  edge  of 
township  150,  range  40. 

From  this  bend  or  angle  of  the  moraine  its  belt  of  knoUy  and  hilly 
or  rolling  drift,  mainly  till,  with  many  bowlders,  occupying  a  width  of 
about  5  miles,  stretches  west-southwesterly  25  miles,  crossing  Hill  and 
Poplar  rivers,  and  passing  by  Badger  Lake  and  other  small  lakes  in  the 
vicinity  of  Erskine,  at  the  head  of  Badger  Creek.  It  includes  much  of 
the  large  wooded  tract,  with  very  plentiful  lakes,  southeast  and  south  of 
Maple  Lake,  and  enters  the  area  of  Lake  Agassiz,  where  it  loses  its 
unevenness  of  contour,  between  the  west  end  of  Maple  Lake  and  the 
Sand  Hill  River.  This  morainic  belt,  lying  just  outside  and  southeast  of 
Lake  Agassiz,  partially  bordered  its  shore,  and  elsewhere  was  separated 
from  it  only  by  a  long  tamarack  swamp,  and  farther  west  by  Maple  Lake, 
with  an  adjoining  narrow  strip  of  lowland. 

Slopes  of  the  ice  sui-face  descended  towai'd  the  angle  of  its  boundary 
from  extensive  areas  on  the  east,  northeast,  and  north;  and  their  conver-, 
gent  drainage  formed  an  exceptionally  large  glacial  river  which  was  laden 
with  much  gravel,  sand,  and  fine  silt,  washed  away  from  the  englacial  drift 
that  had  become  exposed  on  the  thinned  outer  portion  of  the  ice-sheet.  A 
well-defined  watercourse,  which  carried  this  river  from  the  glacial  melting 
at  the  time  of  formation  of  the  moraine,  starts  from  three  lakelets  in  the 
north  half  of  section  34,  township  150,  range  40,  near  the  apex  of  the 
morainic  angle,  and  was  traced  southwestward  and  southward  to  the  Sand 
Hill  River,  passing  obliquely  about  9  miles  through  the  morainic  belt  and 
7  miles  beyond,  across  a  moderately  undulating  expanse  of  till.  In  its  first 
3  miles,  extending  to  the  Hill  River,  in  section  5,  township  149,  range  40, 
the  channel  is  two-thirds  of  a  mile  to  1^  miles  wide,  having  a  smooth  and 


THE  NINTH  OR  LEAF  HILLS  MORAINE.  165 

mostly  flat  bottom  of  stratified  sand  and  gravel.  Along  its  next  2  miles  the 
Hill  River  occupies  its  east  side,  and  close  west  of  this  stream  the  central 
part  of  the  channel  contains  a  kame  or  esker  plateau  of  gravel  and  sand 
which  extends  2  miles  from  north  to  south,  with  a  width  of  a  quarter  of  a 
mile  or  less,  rising  40  to  50  feet  above  the  bottom  of  the  old  watercourse, 
a  half  mile  wide,  west  of  the  plateau.  Continuing  south-southwestward  4 
miles  farther  within  the  moraine,  by  the  west  end  of  a  lake  in  section  24, 
township  149,  range  41,  to  the  Poplar  River,  in  the  southwest  quarter  of 
section  3,  township  148,  range  41,  this  channel  is  a  marshy  hollow,  from  1 
mile  to  only  a  third  of  a  mile  wide.  Beyond  the  morainic  belt,  its  next  2 
miles,  reaching  south  to  Mcintosh,  are  now  part  of  the  valley  of  the  Poplar 
River;  and  its  remaining  5  miles  also  extend  nearly  due  south,  uniting 
with  the  Sand  Hill  River  in  section  10,  township  147,  range  41. 

The  glacial  stream  flowing  through  this  channel  undoubtedly  con- 
tributed a  large  share  of  the  delta,  chiefly  composed  of  sand  and  fine  silt, 
which  was  accumulated  where  the  Sand  Hill  River  emptied  into  Lake 
Agassiz,  at  a  distance  of  about  20  miles  to  the  west.  Other  portions  of 
this  delta  deposit,  though  probably  far  less  in  their  aggregate  amount, 
were  also  brought  by  many  small  streams  and  rivulets  which  flowed  down 
from  the  melting  ice-sheet  along  its  edge  lying  near  the  Sand  Hill  River, 
between  this  old  watercourse  and  the  place  of  disappearance  of  the  moraine 
in  the  lake. 

On  the  area  of  Lake  Agassiz  the  course  of  the  ice  front  forming  its 
northern  border  at  the  time  of  the  Leaf  Hills  moraine  probably  extended 
westward  from  the  vicinity  of  Maple  Lake  to  Beltrami,  the  Goose  Rapids 
of  the  Red  River,  Buxton  and  Reynolds,  and  thence  curved  northwest- 
ward, passing  near  Arvilla,  Larimore,  and  McCanna,  to  the  morainic  islands 
in  the  west  edge  of  Lake  Agassiz,  forming  the  east  side  of  the  Elk  and 
Golden  valleys.  Abundant  bowlders,  many  of  them  of  large  size,  are 
strewn  upon  the  till  which  was  the  bed  of  the  lake  in  the;  part  of  this 
course  lying  south  of  the  Sand  Hill  River  for  6  miles  east  of  Beltrami. 
Farther  west,  in  crossing  the  central  part  of  the  Red  River  Valley,  the 
surface  is  till,  containing  plentiful  small  bowlders  and  gravel,  and  ha^dng 
slight  inequalities  of  contour,  the  small  ridges  and  swells  being  5  to  8  or 


166  THE  GLACIAL  LAKE  AGASSIZ. 

10  feet  above  adjoining  depressions,  remarkably  in  contrast  with  the  very 
flat  surface  of  lacustrine  and  chiefly  alluvial  clay  and  fine  silt,  containing 
no  gravel  or  bowlders,  which  elsewhere  is  the  axial  lowest  portion  of  this 
valley  plain,  continuous,  excepting  on  this  belt,  from  Breckenridge  and 
McCauleyville  to  Winnipeg,  with  widths  on  each  side  of  the  river  varying 
from  a  few  miles  to  15  or  20  miles. 

The  belt  of  till  here  stretching  from  east  to  west  across  the  valley  has 
a  minimum  breadth  of  about  10  miles,  and  probably  comprises  the  mar- 
ginal accumulations  of  the  ice-sheet  during  its  stages  recorded  by  both  the 
Fergus  Falls  and  Leaf  Hills  moraines.  In  the  massive  Leaf  Hills  and 
again  on  the  south  side  of  Devils  Lake  these  moraines  are  merged  together; 
and  such  a  compound  moraine  appears  also  to  have  been  amassed  by  the 
ice-front  in  the  deepest  part  of  the  bordering  glacial  lake.  Upon  this 
broad  tract  the  till  deposited  in  Lake  Agassiz  rises  50  to  75  feet  above  the 
top  of  the  till  along  the  center  of  the  valley  on  the  south  and  north,  where 
it  has  been  overlain  by  later  stratified  silt.  The  moraine  was  not  covered 
by  lacustrine  silt,  which  is  very  scanty  tlu-onghout  the  lake  area,  excepting 
where  great  rivers  brought  in  gravel  and  sand  deltas  and  more  widely 
spread  fine  silt  deposits  of  modified  di-ift  derived  from  the  retreating  ice- 
sheet.  Neither,  on  account  of  its  height,  has  it  become  covered,  subsequent 
to  the  withdrawal  of  the  lake,  by  the  alluvium  of  the  Red  River  and  its 
tributaries,  although  this  sedimentation  has  filled  the  valley  both  above  and 
below  almost  to  the  height  of  the  morainic  belt. 

Where  the  Red  River  cuts  through  this  area  of  till  its  channel  is 
obstructed  by  many  bowlders,  which  form  the  Goose  Rapids,  12  miles  long 
in  the  winding  course  of  the  stream,  next  below  the  mouths  of  the  Groose 
and  Marsh  rivers.  The  descent  of  the  Red  River  along  the  rapids  and 
onward  to  Belmont,  a  distance  of  12  miles  in  due-north  course,  but  about 
twice  as  far  by  the  meanderings  of  the  river,  is  24  feet  in  its  stage  of 
lowest  water,  but  only  14  feet  in  its  highest  floods.  The  plane  of  extreme 
high  water  rises  40  feet  above  the  extreme  low  stage  at  the  head  of  the 
rapids^  and  nearly  as  much  all  the  way  from  Fargo  and  Moorhead  to  Win- 
nipeg; but  at  Belmont,  close  below  the  foot  of  the  rapids,  the  floods  attain 
their  greatest  range  in  the  entire  valley,  50  feet. 


THE  NINTH  OE  LEAF  HILLS  MORAINE.  167 

In  North  Dakota  the  ice  ban'ier  of  Lake  Agassiz  during  the  accumu- 
lation of  the  Leaf  Hills  moraine  is  believed  to  have  curved  to  the  north- 
west, extending  upon  the  area  of  till  along  the  eastern  side  of  the  sand  and 
silt  delta  which  reaches  from  McCanna  35  miles  south  to  Portland.  The 
existence  of  this  large  delta,  evidently  due  to  drainage  from  the  melting 
ice-sheet  without  dependence  on  the  aid  of  any  of  the  present  streams 
having  been  deposited  by  a  glacial  river  flowing  southward  from  the  Elk 
Valley,  implies  that  north  of  it  the  ice  front  was  deeply  incised.  The 
reentrant  angle  probably  moved  gradually  toward  the  noi-th  from  near 
Hatton  to  Larimore  and  McCanna  and  along  the  whole  extent  of  the  Elk 
and  Golden  valleys,  and  the  ice-lobes  stretched  southward  on  each  side  of 
the  delta,  but  were,  like  the  angle,  slowly  undergoing  change  in  their  posi- 
tion by  a  steady  or  mostly  intermittent  recession  from  south  to  north. 

The  islands  of  morainic  till  which  rose  above  the  surface  of  Lake 
Agassiz  at  its  highest  stage  along  a  distance  of  more  than  30  miles  east  of 
the  Elk  and  Grolden  valleys,  between  McCanna  and  Edinbm-g,  were  accu- 
mulated during  this  time  on  the  west  margin  of  the  Minnesota  ice-lobe. 
Their  material  and  that  of  the  beach  ridges  formed  from  their  erosion  were 
derived  from  the  north  and  northeast,  and  contain  scarcely  any  Cretaceous 
shale  from  the  Pembina  Mountain  area.  No  glacial  currents  coming  from 
even  a  few  degrees  west  of  north  seem  to  have  contributed  immediately  to 
the  formation  of  this  moraine,  although  during  earlier  stages  of  the  glacia- 
tion  currents  from  the  north-northwest  mingled  their  di'ift  with  that  from 
the  northeast  upon  this  region.  Numerous "  detailed  notes  of  the  Elk  and 
Golden  valleys  and  of  the  naiTOW  series  of  morainic  hills  on  their  east  side 
are  given  in  Chapter  VI,  in  connection  with  the  description  of  the  asso- 
ciated delta  and  beaches. 

Rising  from  beneath  the  Elk  Valley  delta,  which  occupies  the  western 
margin  of  Lake  Agassiz  between  the  Turtle  and  Goose  rivers,  the  Leaf 
Hills  moraine  seems  to  be  represented  by  a  succession  of  several  more  or 
less  morainic  belts,  formed  on  the  southeastern  side  of  the  Dakota  ice-lobe. 
Subordinate  stages  of  the  glacial  retreat  are  thus  indicated,  belonging  to 
the  time  of  progressive  accumulation  of  the  delta  and  of  the  moraine 
formed  east  of  the  Elk  and  Golden  valleys,  both  of  which,  as  well  as  the 


168  THE  GLACIAL  LAKE  AGASSIZ. 

valley  itself  aud  the  glacial  river  pouring  southward  in  it,  were  gi'ad- 
ually  extended  from  south  to  north  as  the  ice  front  with  its  deep  indenta- 
tion receded. 

The  most  southeastern  of  these  belts  consists  of  somewhat  rolling  till 
west  of  Golden  Lake,  in  township  147,  range  55,  and  includes  the  area  of 
very  abundant  bowlders  which  strew  the  bluifs  of  Fingals  Creek  or  "Rocky 
Run,"  in  township  148,  range  56.  Thence  a  belt  of  morainic  knolls  and 
hillocks,  10  to  40  feet  high  and  occupying  a  width  of  half  a  mile,  extends 
northwestward  through  sections  34  and  27,  township  149,  range  57,  and 
rises  in  hills  50  to  75  feet  above  the  general  level  in  the  southwest  part  of 
township  150,  range  57,  with  numerous  lakelets  in  the  adjoining  depres- 
sions. This  moraine  continues  westward  in  knolls  and  hills  25  to  50  feet 
high  to  its  junction  with  the  Fergus  Falls  moraine,  in  the  southern  part  of 
township  150,  range  58,  beyond  which  these  two  moraines  seem  to  form  a 
compound  series,  in  many  places  very  conspicuously  developed,  to  the  west 
part  of  the  Turtle  Mountain. 

Other  morainic  tracts,  probably  all  extending  southward  to  join  the 
preceding  east  of  its  union  with  the  Fergus  Falls  moraine,  were  observed 
on  the  western  shore  of  Lake  Agassiz,  as  follows:  First,  somewhat  rolling 
and  hilly  till  8  to  10  miles  south  of  Larimore;  second,  knolls  and  swells  of 
till,  sprinkled  with  abundant  bowlders,  in  the  southwest  part  of  Elm  Grove 
township,  crossed  by  the  Great  Northern  Railway  between  the  Herman 
beach  and  Shawnee  station ;  and,  third,  moderately  rolling  and  occasionally 
hilly  till,  with  many  bowlders,  in  the  east  part  of  Oakwood,  forming  a  belt 
2  to  3  miles  wide,  which  lies  about  3  miles  west  of  the  last  and  is  crossed 
by  the  railway  at  and  east  of  Niagara. 

Similar  recessional  morainic  accumulations  of  till  and  bowlders  were 
also  dropped  on  the  western  side  of  the  Minnesota  ice-lobe  during  its 
retreat  across  the  Red  River  Valley,  where  it  was  rapidly  melted  back  by 
the  laving  action  of  Lake  Agassiz,  between  the  chief  stages  of  formation 
of  the  ninth  and  tenth  or  Leaf  Hills  and  Itasca  moraines.  In  this  class 
may  belong  the  remarkable  profusion  of  bowlders  found  at  a  few  points  in 
Gilby (township  153,  range  63),  one  of  which  is  commonly  called  "The 
Island."     Among  other   noteworthy  localities  of  plentiful    bowlders,   the 


STUMP  AND  DEVILS  LAKE.  169 

shores  and  bed  of  the  Salt  Lake  of  Park  River,  in  section  36,  Martin 
(township  158,  range  62),  should  be  mentioned,  from  which  a  belt  of  occa- 
sional bowlders  in  the  lacustrine  silt  extends  northward  to  the  vicinity  of 
Glasston.  This  belt  is  perhaps  again  recognizable  in  Minnesota,  on  the 
east  side  of  the  broad  alluvial  area  adjoining  the  Red  River,  .where  many 
bowlders  are  spread  on  a  flat  or  slightly  undulating  tract  of  till  a  few  miles 
wide,  extending  from  Euclid  south  to  Shirley,  succeeded  on  the  northeast 
by  silt  and  southward  by  till,  with  few  bowlders. 

Through  the  north  half  of  township  150,  range  59,  the  double  Fergus 
Falls  and  Leaf  Hills  moraine  consists  of  swells,  knolls,  and  hills,  20  to  50 
or  60  feet  high  above  the  smoothly  undulating  surface  of  till  on  each  side. 
In  the  south  half  of  this  township  the  thickness  of  the  sheet  of  till,  extend- 
ing as  a  plain  toward  the  Sheyenne,  is  found  to  be  only  10  to  20  feet,  below 
which  the  wells  enter  the  Cretaceous  shale,  obtaining  slightly  brackish  and 
saline  water.  On  the  southern  and  western  shores  of  Stump  Lake,  massive 
hills,  called  the  Blue  Mountains,  consisting  superficially  of  morainic  drift, 
but  probably  ha^dng  a  nucleus  of  Cretaceous  shale,  rise  100  to  200  feet  or 
more  above  this  lake,  their  highest  points  being  100  to  150  feet  above  the 
plain  on  the  south,  which  close  to  the  hills  is  overwashed  gravel  and  sand, 
descending  10  or  20  feet  in  its  width  of  a  half  mile  to  IJ  miles.  This  is 
succeeded  upon  a  width  of  2  or  3  miles  next  to  the  south  by  a  very  flat 
expanse  of  till,  the  continuation  of  the  same  plain,  profusely  sprinkled  with 
bowlders,  continuing  to .  the  Sheyenne  Valley,  which  here  has  a  depth  of 
about  150  feet  below  the  plain  and  a  width  of  a  half  mile  to  1  mile. 

Along  the  entire  south  side  of  Devils  Lake  (PI.  XVIII),  extending 
more  than  30  miles  from  Jerusalem  to  Minnewaukan,  this  compound 
morainic  belt  is  magnificentlj"  developed,  in  many  portions  forming  hills, 
knolls,  and  ridges  of  till,  very  rough  in  outline  and  bristling  with  multi- 
tudes of  bowlders,  of  all  sizes  tip  to  10  feet  in  diameter,  on  a  width  that 
varies  from  1  to  5  miles.  Most  of  these  hills  rise  50  to  150  feet  above  the 
lake,  and  appear  by  their  small  area  and  glacial  features  to  consist  wholly 
of  di-ift;  but  Sully s  Hill  and  others  2  to  6  miles  east  of  Fort  Totten  consti- 
tute massive  ridges  200  to  275  feet  above  the  lake,  and  nearlv  equal  heights 
are  reached  by  the  Crow  Hills,  4  to  6  miles  west  of  Fort  Totten.  As  was 
stated  of  the  similarly  massive  hills  south  of  Stump  Lake,  these  are  prob- 


170  THE  GLACIAL  LAKE  AGASSIZ. 

ably  in  their  central  part  the  Fort  Pierre  shale,  although  no  clear  exposures 
of  it  were  found,  so  completely  are  the  slopes  and  summits  mantled  with 
their  very  rough  morainic  accumulations  and  innumerable  bowlders.  On 
the  lake  shore  near  the  Fort  Totten  landing,  and  on  the  hills  along  the 
next  6  miles  eastward,  a  large  proportion  of  the  bowlders  consists  of  Silu- 
rian dolomitic  limestone,  like  the  strata  which  outcrop  near  Winnipeg  in 
Manitoba.  Limestone  masses  5  to  10  feet  in  diameter  are  occasionally 
found  in  great  numbers  with  the  Archean  gi-anite  and  gneiss  bowlders, 
which  elsewhere  form  on  an  average  fully  99  per  cent  of  the  large  bowl- 
ders of  North  Dakota,  so  far  as  I  have  observed,  excepting  only  in  the 
vicinity  of  Butte  Mashue  (p.  155),  where  again  these  limestone  bowlders 
are  very  abundant. 

Perhaps  the  most  striking  feature  of  this  morainic  belt  south  of  Devils 
Lake  is  its  overwashed  gravel  and  sand,  Avhich  generally  border  the  southern 
side  of  the  hills,  descending  from  them  in  graceful  slopes.  This  deposit  is 
most  grandly  exhibited  between  3  and  4  miles  east  of  the  fort.  The  upper 
edge  of  the  overwashed  slope,  there  consisting  of  gravel  and  sand,  with 
rounded  and  subangular  cobbles  of  all  sizes  up  to  a  foot  in  diameter,  rests, 
at  about  225  feet  above  the  lake,  upon  the  southern  sid-e  of  the  morainic 
hills,  with  their- vast  accumulations  of  bowlders,  which  rise  only  from  5  or 
10  to  40  feet  higher.  The  gravel  and  sand  form  a  flat  tract  that  declines 
from  the  moraine  at  the  rate  of  30  or  40  feet  per  mile ;  and  these  fluvial 
beds  have  a  considerable  thickness,  as  is  shown  by  watercourses  which 
have  become  channeled  to  depths  of  50  and  even  100  feet  without  dis- 
closing bowlders. 

Devils  Lake  and  Stump  Lake  were  found  by  my  leveling  in  August, 
1887,  respectively,  1,432  and  1,417  feet  above  the  sea;  but  both  were 
depressed  about  2  feet  lower  by  the  drought  of  the  following  two  years. 
These  lakes,  having  very  irregular  outlines,  with  numerous  windings  and 
long  bays  or  arms,  probably  lie  in  valleys  of  a  preglacial  river  and  its  trib- 
utaries, elsewhere  filled  with  drift.  Devils  Lake  attains  a  maximum  depth 
of  75  or  80  feet  in  the  eastern  portion  of  its  broadest  area,  and  the  north- 
east arm  of  Stump  Lake  is  said  to  be  in  ^ome  places  100  feet  deep.  The 
ancient  watercourse  appears  to  have  flowed  eastward  directly  to  the  Red 
River  Valley.     Its  obstruction  by  drift  during  the  Glacial  period,  and  the 


3 
03 


BIG  OR  MAUVAIS  BUTTE.  171 

lobate  outline  of  the  ice-sheet  in  its  retreat,  with  its  morainic  accumulations, 
have  given  to  the  postglacial  Sheyenne  River  its  circuitous  course  far  to 
the  south,  over  the  Cretaceous  plain,  thinly  covered  by  drift.  The  country 
adjoining  these  lakes  generally  consists  of  the  Fort  Pierre  shale  to  a  height 
10  to  25  feet  above  their  levels,  as  is  ascertained  by  wells,  while  in  the 
Big  Butte,  and  probably  also  in  the  most  massive  of  the  hills  on  their 
southern  shores,  the  shale  rises  much  higher.  Both  lakes  are  now  without 
outlets,  but  distinct  beach  lines,  which  are  described  in  Chapter  XI,  in  the 
discussion  of  past  climatic  changes  in  this  district,  show  that  during  the 
recession  of  the  ice  they  were  raised  nearly  25  feet  above  the  present  level 
of  Devils  Lake,  being  then  confluent,  with  an  outlet  from  the  southwestern 
arm  of  Stump  Lake  southward  to  the  Sheyenne. 

West  of  Minnewaukan  the  compound  Fergus  Falls  and  Leaf  Hills 
moraine  forms  a  belt,  2  or  3  miles  wide,  of  low  hills,  ridges,  and  swells  of 
till,  with  plentiful  bowlders,  rising  25  to  50  or  75  feet,  but  inconspicuous 
in  any  distant  view,  through  the  centi'al  and  northwest  part  of  township 
153,  range  68 ;  and  thence  curving  noi'thward  it  passes  through  town- 
ship 154,  range  69,  to  the  west  and  highest  portion  of  the  Big  Butte,  or 
Mauvais  Butte,  as  it  is  called  by  the  French  and  Indians  of  Turtle  Moun- 
tain. This  prominent  massive  ridge  of  high  land  extends  10  miles  from 
east  to  west  and  west-northwest,  tlu-ough  the  north  edge  of  township  154, 
range  68,  the  northeast  corner  of  the  next  township  west,  and  the  southern 
third  of  township  155,  range  69.  Its  eastern  6  miles,  to  the  west  side  of 
section  1,  township  154,  range  69,  has  a  very  smooth  contour,  and  con- 
sists superficially  of  till,  with  the  scanty  proportion  of  bowlders  generally 
observable  on  its  lower  areas.  No  morainic  accumulations  were  seen  on 
this  part  of  the  Big  Butte,  and  the  drift-sheet  here  is  doubtless  of  similar 
depth  (25  to  50  or  75  feet)  as  on  the  surrounding  smoothly  undulating 
countiy,  above  which  this  ridge  rises  150  to  200  feet,  to  a  height  1,650  to 
1,700  feet  above  the  sea.  Its  top  along  this  distance  is  nearly  level  or  only 
slightly  undulating  and  rounded  upon  a  width  of  1  to  1 1  miles. 

But  the  western  4  miles  of  the  ridge  is  covered  with  irregular  morainic 
deposits  and  a  wonderful  profusion  of  bowlders,  giving  to  it  a  very  rough 
contour,  strongly  in  contrast  with  that  on  the  east.  A  slight  depression, 
sinking  to  about  1,600  feet  above  the  sea,  intervenes  between  the  smooth 


172  THE  GLACIAL  LAKE  AGASSIZ. 

and  the  moraiuic  portions ;  and  the  latter,  to  which  the  name  Big  Butte  is 
commonly  limited,  rises  to  1,750  and  1,800  feet,  or  250  to  300  feet  above 
its  base,  the  culminating  point  being  near  its  west  end.  This  Cretaceous 
highland,  veneered  with  two  diverse  phases  of  the  glacial  drift,  is  situated 
8  to  18  miles  northwest  of  the  west  end  of  Devils  Lake.  Il  appears  to  be 
allied  geographically  and  geologically  with  the  highest  of  the  hills  south 
of  Devils  and  Stump  lakes;  and  the  northwestward  continuation  of  the 
old  valley  now  filled  by  those  lakes  is  probably  represented  along  a  dis- 
tance of  30  miles  north  and  north-northwest  of  the  Big  Butte  by  Ibsen, 
Hurricane,  Grass,  Island,  and  Long  lakes. 

Beyond  the  Big  Butte  this  morainic  belt  is  well  developed  in  knolls 
and  hills  occupying  a  width  of  several  miles,  onl}  moderately  elevated 
above  the  general  level,  through  township  155,  range  70,  and  about  Horse 
Shoe  and  Broken  Bone  lakes  (the  latter  named  from  buffalo  bones  broken 
for  exti-acting  the  marrow  in  making  pemmican),  in  township  156,  range  71. 
Next  to  the  north  of  Limekiln  and  Broken  Bone  lakes  and  of  Pleasant 
Lake  station  and  Rugby  Junction,  on  the  Great  Northern  Railway,  an 
extensive  area  is  covered  by  morainic  hills,  with  abundant  bowlders,  rising 
50  to  100  feet  or  more  above  the  intervening  hollows  and  100  to  150 
feet  above  the  smoothly  undulating  surface  east,  north,  and  west.  This 
morainic  area,  probably  representing  the  combined  Fergus  Falls,  Leaf 
Hills,  and  Itasca  moraines,  extends  about  15  miles  north  from  the  railway 
to  Island  Lake  and  Ox  Creek,  and  an  equal  or  somewhat  greater  distance 
from  east  to  west  across  ranges  71,  72,  and  the  east  half  of  73,  pressing 
close  to  the  Bottineau  branch  railway  in  the  northeast  part  of  township 
157,  range  73,  and  terminating  thence  along  a  south-to-north  line  which 
was.  also  the  east  shore  of  the  glacial  Lake  Souris,  passing  about  4  miles 
east  of  Round  Lake  and  Barton.  North  of  this  remarkable  development 
of  the  moraines  a  smoothly  undulating  or  only  moderately  rolling  sur- 
face of  intermorainic  till,  with  few  bowlders,  stretches  from  Island  Lake 
and  Ox  Creek  across  the  next  15  miles  to  the  southern  base  of  Turtle 
Mountain. 

Gravel,  sand,  and  silt,  deposited  in  Lake  Souris,  extend  from  Dunseith 
southwest  to  Willow  City  and  the  Souris  River,  excepting  a  belt  of  moder- 


TUETLE  MOUNTAIN.  173 

ately  undulating  till,  about  a  mile  wide,  with  frequent  bowlders,  rising  10 
feet  above  the  surface  eastward,  which  crosses  the  central  part  of  township 
160,  range  74,  in  a  north-northwest  course,  having  a  descent  of  40  feet 
within  the  tirst  mile  on  its  west  side.  The  belt  may  represent  the  course 
of  the  combined  Fergus  Falls  and  Leaf  Hills  moraine,  across  the  eastern 
margin  of  the  ai'ea  of  Lake  Souris,  passing  thence  northward  by  Lords 
Lake  to  Butte  St.  Paul,  Bur  Oak,  and  Bear  Buttes,  on  the  west  part  of  the 
Turtle  Mountain  area. 

The  highland  of  Turtle  Mountain,  extending  about  40  miles  on  the 
international  boundary,  with  two-thirds  as  great  width,  diversified  by 
many  subordinate  hills  and  short  ridges,  50  to  300  feet  above  adjoining 
depressions,  rises  with  a  massive  general  form,  suggesting,  as  seen  from 
some  distant  points  of  view,  the  rounded  back  of  a  turtle;  but  as  seen 
from  the  south  or  north  its  many  hills  and  buttes  present  a  serrated  out- 
line. Its  altitude  above  the  surrounding  country  is  300  to  800  feet,  the 
summits  of  its  hig-hest  hills  being  about  2,500  feet  above  the  sea.  Beneath 
a  veneering  of  glacial  drift,  which  is  in  large  part  morainic  and  generally 
strewn  with  many  bowlders,  averaging  perhaps  50  to  75  feet  in  thickness. 
Turtle  Mountain  consists  of  nearly  horizontally  bedded  Laramie  strata, 
chiefly  shales,  with  very  thin  seams  of  lignite.  At  or  below  the  base  of 
this  highland  the  fresh-water  Laramie  formation  rests  on  the  marine  series, 
which  comprises  the  Fox  Hills  sandstone  and  Fort  Pierre  shale,  the  two 
great  shale  formations  being  separated  by  a  sandstone  stratum  which  out- 
crops on  Ox  Creek  and  Willow  River,  and  on  the  Souris  River  between 
Minot  and  its  most  southern  bend. 

TENTH   OR  ITASCA  MORAINE. 

On  the  south  side  of  Pokegama  and  Leech  lakes,  and  westward  to 
Little  Man  Trap  Lake  and  the  southern  arms  of  Lake  Itasca,^  the  tenth 


'This  lake  lias  been  called  by  the  Ojibways,  from  time  immemorial,  Omusbkozo-Sagaiigun  (Elk 
Lake),  according  to  Rev.  J.  A.  Gilfillan  in  Fifteenth  Annual  Report,  Geol.  and  Nat.  Hist.  Survey  of 
Minnesota,  for  1886,  p.  460.  Its  present  name  was  given  to  it  by  Schoolcraft  at  the  time  of  his 
exploration  of  the  sources  of  the  Mississippi  iu  1833.  Rev.  W.  T.  Boutwell,  who  was  a  member  of 
that  expedition,  -was  asked  by  Schoolcraft  to  give  the  Latin  -words  meaning  ''truth"  and  "head,''  and 
from  these  words,  Veritas  and  cajnit,  the  name  was  made  by  writing  them  together  and  cutting  oft',  like 
Procrustes,  the  first  and  the  last  syllables.  (Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Final  Report, 
Vol.  I,  p.  51.  "A  recent  visit  to  Lake  Itasca,"  by  Warren  Upbam,  Bulletin  of  the  Minnesota  Academy 
of  Natural  Sciences,  Vol.  Ill,  pp.  284-292.) 


174  THE  GLACIAL  LAKE  AGASSIZ. 

or  Itasca  moraine  occupies  a  width  of  5  to  10  miles.  Its  hills  of  till,  with 
abundant  bowlders,  rise  25  to  50.  feet  above  the  hollows  and  frequent  lakes, 
and  the  elevation  of  the  morainic  belt  averages  100  to  150  feet  above  the 
general  level  of  the  country.  Following  the  main  watershed  onward,  it 
bends  to  the  northwest  and  north  between  Lake  Itasca  and  the  source  of 
the  Red  River,  and  continues  northward  past  the  west  side  of  the  Upper 
Rice  Lake  to  Clearwater  Lake,  about  which  it  is  well  developed,  and  a 
few  miles  farther  north  it  enters  the  area  of  Lake  Agassiz,  some  10  miles 
southwest  of  Red  Lake. 

The  southern  border  of  the  Itasca  moraine,  where  it  is  crossed  by  the 
road  from  Park  Rapids  to  Lake  Itasca,  is  called  Stony  Ridge.  It  consists 
of  small  ridges  of  till,  trending  from  southeast  to  northwest,  with  very 
plentiful  bowlders,  all  Archean  from  the  northeast  and  north,  chiefly 
granite  and  gneiss.  No  limestone  bowlders  were  observed  there;  but  in 
the  vicinity  of  the  White  Earth  Agency  and  about  Red  Lake  they  form 
a  considerable  proportion  of  the  drift,  ha\-ing  been  brought  by  glacial 
currents  from  the  region  of  Lakes  Winnipeg  and  Manitoba.  Very  irregu- 
larly grouped  morainic  hills,  50  to  100  feet  high,  rise  on  each  side  of  the 
road,  which  winds  and  climbs  and  descends  over  them,  along  a  distance  of 
about  8  miles  from  Stony  Ridge  to  Mr.  Peter  Turnbull's  claim  cabin,  on 
the  southeast  arm  of  Lake  Itasca. 

Many  empty  hollows  20  to  40  feet  deep  are  seen  beside  this  road, 
being  kettle-holes,  as  they  are  called,  well  known  as  characteristic  of 
morainic  di-ift  deposits.  Several  similar  hollows,  but  of  larger  size  and 
greater  depth,  contain  a  series  of  picturesque  little  lakes,  lying  east  of  the 
road,  in  descending  order  from  south  to  north,  the  lowest  having  an  outlet 
to  Lake  Itasca  by  Mar}'  Creek.  These  small  lakes  fill  depressions  of  the 
diift,  and  Lake  Itasca  doubtless  owes  its  existence  to  greater  thickness  of 
the  drift  in  the  valley  at  the  mouth  of  the  lake  and  for  several  miles  down 
the  Mississippi,  rather  than  to  greater  prominence  of  the  underlying  rock 
there.  But  the  great  valley,  150  to  200  feet  deep  and  2  to  4  miles  wide,  in 
which  lie  Lake  Itasca  and  the  Mississippi  northward  to  Craig's  crossing, 
and  to  its  rapids  over  bowlders  in  section  8,  township  145,  range  35,  and 
the  similar  but  smaller  valleys  of  the  La  Salle,  Hennepin,  and  Schoolcraft 


THE  TENTH  OR  ITASCA  MOEAINE.  175 

rivers,  successively  tributary  to  tlie  Mississippi  from  the  south  between 
Lakes  Itasca  and  Pemidji,  existed  as  grand  topographic  features  of  the 
country  before  the  Glacial  period,  being  then  occupied  by  streams  flowing 
in  the  same  northward  direction  as  now. 

The  ice  front  forming  the  northern  boundary  of  Lake  Agassiz  at  the 
time  of  accumulation  of  the  Itasca  moraine  probably  passed  not  far  west 
of  Red  and  Roseau  lakes  to  the  vicinity  of  Winnipeg.  The  remarkable 
group  of  eskers  east  of  Birds  Hill  station  of  the  Canadian  Pacific  Railway 
was  perhaps  deposited  at  the  angle  where  the  border  of  the  ice-sheet 
turned  back  southwestward.  In  that  course  it  seems  to  have  reached 
across  the  lake  area  to  the  bowlder-strewn  escarpment  of  the  Pembina 
Mountain  east  of  Thornhill,  and  beyond  to  have  passed  south  along  the 
west  shore  of  Lake  Agassiz  into  North  Dakota. 

Its  terminal  moraine,  about  50  miles  south  of  the  international  bound- 
ary, consists  of  two  crescentic  series  of  knolls  and  hills,  with  multitudes 
of  bowlders,  in  townships  155  and  156,  ranges  56  and  57,  crossed  by  the 
head  streams  of  Forest  River  and  culminating  in  Pilot  Knob.^  Thence 
the  front  of  this  great  ice-lobe  appears  to  have  extended  westward  to  the 
north  side  of  Devils  Lake,  and  north-northwestward  by  the  east  part  of 
Turtle  Mountain,  again  entering  Manitoba  and  passing  along  the  moraine 
of  the  west  part  of  the  Tiger  Hills  and  of  the  Brandon  and  Arrow  hills. 

Upon  the  country  east  and  north  of  Devils  Lake  the  Itasca  moraine 
seems  to  be  divided  into  several  belts,  which  are  marked  by  abundant 
bowlders  and  by  knolls  and  hillocks  of  till  and  others  of  kame  gravel  and 
sand,  sometimes  occupying  a  width  of  a  quarter  of  a  mile,  and  rising  only 
10  to  25  feet  above  the  adjoining  surface  of,  smoothly  undulating  till,  such 
as  are  crossed  by  the  railway  within  2  miles  west  of  Lakota  and  at  two  or 
three  places  in  township  153,  ranges  62  and  63,  north  of  the  east  part  of 
Devils  Lake,  and  again  forming  tracts  of  notably  rolling  and  hilly  surface 
from  1  to  6  miles  in  width,  such  as  are  crossed  to  the  number  of  two  or 
three  in  a  journey  from  Milton,  Osnabrock,  or  Langdon  southwest  to 
Devils  Lake,  and  likewise  in  traveling  from  Devils  Lake  due  north  to  the 

'U.  S.  Geol.  Survey,  Bnlletin  No.  39,  pp.  61,  67-70.  These  very  interesting  moraiuic  loops  are 
described  in  Chapter  VI,  in  connection  with  the  Herman  shore-line  west  of  the  Elk  and  Golden 
valleys. 


176  THE  GLACIAL  LAKE  AGASSIZ. 

international  boundary.  Both  the  narrow  and  the  wide  morainic  belts 
mentioned  trend  mainly  from  southeast  to  northwest,  and  were  apparently 
accumulated  on  the  southwestern  border  of  the  ice-sheet  during  slight 
pauses  of  its  retreat,  perhaps  being  all  contemporaneous  with  the  single 
broad  and  massive  Itasca  moraine  in  northern  Minnesota. 

The  outermost  of  these  belts,  varying  from  a  half  mile  to  1  mile  or 
more  in  width,  here  and  there  marked  by  hills  50  to  100  feet  high,  but 
more  commonly  by  lower  and  often  very  scanty  knolls  and  swells,  passes 
from  east  to  west  about  3  miles  north  of  the  city  of  Devils  Lake,  by  the 
south  end  of  Dry  Lake,  through  the  northeast  part  of  township  154,  range 
66,  and  thence  by  a  somewhat  devious  course  through  the  center  of  town- 
ship 155,  range  67  (there  being  on  the  west  side  of  a  chain  of  lakes  which 
occupies  unfilled  portions  of  the  preglacial  or  interglacial  channel  of  the 
Mauvaise  Coulee),  and  thi'ough  the  south  half  of  township  156,  range  68, 
to  the  southwest  side  of  Hurricane  Lake,  from  which  it  runs  westward, 
becoming  merged  with  the  Leaf  Hills  moraine  in  the  large  morainic  tract 
north  of  Broken  Bone  Lake.  The  farther  course  of  this  belt  forms  a 
south-to-north  series  of  drift  hills  on  the  west  shore  of  Long  Lake,  and  it 
is  doubtless  traceable  thence  northward  to  the  Turtle  Mountain.  Probably 
also  one  or  more  of  the  wide  belts  of  rolling  and  hilly  di'ift  observed  north- 
east and  north  of  Devils  Lake  continue  westerly  to  the  east  part  of  this 
massive  highland,  contributing  to  its  morainic  di-ift  covering;  but  only 
scanty  morainic  hillocks  were  seen  in  the  vicinity  of  Rolla  and,  indeed, 
along'  the  whole  eastern  and  southern  base  of  the  mountain  area. 

The  continuation  of  the  Itasca  moraine  in  southwestern  Manitoba 
extends  northerly  from  the  east  end  of  Turtle  Mountain,  by  Killaruey,  to 
the  northern  part  of  Pelican  Lake,  a  distance  of  about  25  miles.  Thence 
it  extends  west-northwest  20  miles,  forming  the  west  pai-t  of  the  Tiger 
Hills  in  their  extent  along  the  north  side  of  Langs  Valley  and  the  Souris 
to  township  7,  range  19,  where  it  again  bends  to  the  north  and  holds  that 
course  10  or  12  miles  to  the  prominent  Brandon  Hills.  Here  again  it  turns 
to  the  west,  making  a  sharp  angle,  but  within  a  few  miles  it  sinks  to  the 
general  level  of  the  adjoining  country  and  loses  its  distinctive  character. 
Proceeding  onward  to  the  west  about  20  miles,  this  moraine  is  next  found 


THE  ELEVENTH  OE  MESABI  MOEAINE.  177 

on  the  north  side  of  the  Assiniboine  a  few  miles  northwest  of  Griswold, 
and  thence  it  takes  a  northwest  course,  lying  mostly  from  5  to  8  or  10  miles 
northeast  of  the  Assiniboine  and  approximately  parallel  with  it  to  the 
Arrow  River  and  Bird  Tail  Creek,  beyond  which  I  have  no  definite  infor- 
mation of  its  farther  com-se.  On  both  sides  of  the  Arrow  River  it  rises  in 
prominent  elevations,  with  characteristically  rough  contour  and  plentiful 
bowlders,  and  this  portion  is  called  the  Arrow  Hills.  The  ascertained 
extent  of  this  moraine  in  Manitoba,  known  in  successive  parts  as  the  Tiger, 
Brandon,  and  Aitow  hills,  is  about  125  miles.  Its  general  course  is  north- 
west, but  within  the  Souris  basin  and  that  of  the  head  streams  of  the 
Pembina,  on  the  north  side  of  Turtle  Mountain,  it  is  deflected  about  25 
miles  to  the  northeast.  The  ice-sheet  was  there  indented  by  two  reentrant 
angles,  one  having  its  apex  in  the  range  of  the  Tiger  Hills,  near  Poors 
Lake,  a  few  miles  north  of  the  north  end  of  Pelican  Lake,  and  the  other  in 
the  Brandon  Hills.  The  glacial  Lake  Souris,  dammed  by  the  ice-sheet  and 
probably  causing  its  indentations  along  the  course  of  this  moraine,  then 
filled  the  Souris  basin  and  outflowed  around  the  south  side  of  Turtle  Moun- 
tain and  Devils  Lake,  being  tributary  to  Lake  Agassiz  by  the  Sheyeune.^ 

ELEVENTH   OR  MESA3I  MORAINE. 

The  development  of  the  Mesabi^  moraine,  and  of  the  foregoing  mo- 
raines, in  northeastern  j\Iinnesota  eastward  from  the  headwaters  of  the 
Mississippi  River,  and  the  still  more  northern  twelfth  or  Vermilion  moraine, 
I  have  described  from. exploration  during  the  year  1893  for  the  Greological 
Survey  of  Minnesota.^  The  Embarras  River,  in  its  passage  tln-ough  the 
high  granite  belt  of  the  Giants  or  Mesabi  Range  and  the  adjoining  Mesabi 

'  Detailed  descriptions  of  this  moraine  west  of  Pelican  Lake,  on  the  west  part  of  the  Tiger  Hills 
(which  the  Souris  River  intersects  in  a  gorge  350  feet  deep),  and  in  the  Brandon  Hills  and  Arrow  Hills, 
are  presented  in  the  Annual  Report  of  the  Geol.  and  Nat.  Hist.  Survey  of  Canada,  new  series.  Vol.  IV, 
for  1888-89,  pp.  33-36  E. 

''This  word,  recently  often  spelled  Mesaba,  is  stated  by  Rev.  J.  A.  Gilfillan  to  be  the  Ojibway 
name  of  a  giant  of  immense  size  who  was  a  cannibal.  The  Ojibways  at  Grand  Portage,  according  to 
Prof.  N.  H.  Winchell,  represent  this  giant  as  buried  beneath  the  hills  of  the  Mesabi  Range,  the  various 
hills  covering  different  members  of  his  body.  (Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Fifteenth 
Annual  Report,  for  1886,  p.  456.)  The  Giants  Range  and  Mesabi  Range,  however,  as  these  names  are 
now  applied  by  Professor  Winchell  (see  the  preceding  Chapter  II,  p.  31),  are  distinctly  separate  but 
contiguous  and  parallel  ranges  of  hills. 

=  Geol.  and  Nat.  Hist.  Survey  of  Minn.,  Twenty-second  Annual  Report,  for  1893  (pub.  1894),  pp. 
45-52,  with  map. 

MON  XXV 12 


178  THE  GLACIAL  LAKE  AGASSIZ. 

moraine,  forms  a  series  of  six  or  seven  long  and  narrow  lakes,  indicating 
that  a  larger  river  flowed  here  during  the  recession  of  the  ice-sheet,  its 
deeply  eroded  channel  having  since  been  partially  filled  by  alluvium  from 
tributaries. 

Continuing  westward,  the  Mesabi  moraine  is  apparently  represented 
by  hilly  drift  deposits  north  of  Pokegama  Falls  of  the  Mississippi,  about 
Bowstring  Lake,  the  head  of  the  Big  Fork  of  Rainy  River,  and  on  the 
northeast  side  of  Lake  Winuebagoshish.  Thence  it  passes  west  and  north- 
west by  the  sources  of  Turtle  River  to  the  conspicuous  morainic  ridge  of 
till  with  multitudes  of  bowlders  which  forms  the  tongue  of  land,  9  miles 
long  and  about  2  miles  wide,  between  the  south  and  north  parts  of  Red 
Lake,  extending  westward  to  the  Narrows,  with  a  height  of  100  to  200 
feet  above  the  lake.  At  the  NaiTOws  this  moraine  sinks  beneath  the  high- 
est level  of  the  glacial  Lake  Agassiz,  and  it  forms  no  noteworthy  knolls 
or  hills  ^^sible  from  Red  Lake  toward  the  west  or  northwest. 

The  ice  barrier  of  Lake  Agassiz  at  the  time  of  the  Mesabi  moraine 
probably  extended  thence  northwest  and  north  across  the  area  of  Beltrami 
Island  (described  in  Chapter  VI),  and  thence  farther  northward  and  west- 
ward to  the  south  ends  of  Lakes  Winnipeg  and  Manitoba,  giving  to  this 
glacial  lake  a  length  of  more  than  300  miles.  Morainic  drift  deposits, 
with  plentiful  bowlders  and  typically  rough  contour,  form  the  eastern 
end  of  the  Tiger  Hills,  in  township  7,  ranges  9  and  10,  crossed  by  the 
road  running  south  from  Treherne ;  and  this  tract,  clearly  distinct  from  the 
Itasca  moraine,  which  forms  the  western  end  of  this  range  of  hills,  appears 
to  mark  where  the  southern  extremity  of  the  ice-lobe  west  of  Lake  Agassiz 
still  abutted  on  the  north  end  of  the  Pembina  Mountain  escarpment  and  on 
the  liighland  south  of  the  Assiniboine  delta  during  the  accumulation  of  the 
eleventh  or  Mesabi  moraine.  The  highest  portion  of  tliis  delta  west  of 
Brandon,  the  Big  Slough,  extending  thence  west  from  Alexander  to  Gris- 
wold,  and  the  gap  by  which  the  Souris  River  flows  tlu-ough  the  Itasca 
moraine,  forming  the  western  part  of  the  Tiger  Hills,  between  its  elbow 
and  Gregory's  mill,  all  bear  testimony,  as  shown  in  the  description  of  the 
Assiniboine  Delta  in  Chapter  VI,  that  for  some  time  the  embayed  portion 
of  this  lake  west  of  Treherne  Avas  held  by  this  ice-lobe  at  a  height  con- 


KAMES,  ESKEES,  AND  VALLEY  DRIFT.  179 

siderably  above  that  of  the  main  body  of  the  glacial  lake  with  which 
it  became  united  by  the  recession  of  the  ice-sheet.  Farther  toward  the 
northwest  the  glacial  border,  during  the  Mesabi  stage,  and  probably 
during  several  later  stages  of  pause  or  readvance  interrupting  its  general 
retreat,  rested  on  the  highlands  of  the  Riding  and  Duck  mountains  and  the 
Porcupine  and  Pasquia  hills,  and  held  on  its  west  side  the  glacial  Lake 
Saskatchewan,  which  outflowed  through  the  Qu'Appelle  and  Assiniboine 
rivers  to  Lake  Agassiz. 

MODIFIED    OK   ASSORTED    DRIFT. 

The  modified  drift  comprises  sediments  of  gravel,  sand,  clay,  and  silt 
that  were  derived  directly  from  the  ice-sheet,  but  were  modified  by  cur- 
rents of  water,  which  assorted,  transported,  and  deposited  them.  This  class 
of  drift  occurs  in  many  diverse  forms.  Some  of  its  beds  were  subglacial 
and  others  were  accumulated  at  the  margin  of  the  ice;  but  the  writer 
believes  that  far  the  greater  part  of  the  modified  di'ift  was  englacial  at  the 
time  of  the  final  melting,  and  was  then  washed  away  from  the  ice  border 
by  the  streams  of  its  ablation  and  by  rains. 

McGee^  and  Chainberlin^  have  judiciously  proposed  the  restriction  of 
the  term  kames  to  the  knolls,  hillocks,  and  short  ridges  of  sand  and  gravel 
which  were  heaped  at  the  mouths  of  brooks  and  rivers  where  they  left 
their  ice-walled  channels  and  were  spread  out  inore  widely,  thereby  losing 
their  velocity  and  carrying  power,  on  the  adjoining  land  sm-face.  These 
deposits  are  frequent  on  many  portions  of  the  general  drift-sheet,  but  are 
most  fully  developed  in  connection  with  the  terminal  moraines. 

Prolonged  ridges  of  gravel  and  sand,  or,  in  some  tracts,  of  fine  silt  (as 
described  by  McGee  in  northeastern  Iowa),  narrow  and  bordered  by  steep 
slopes  on  each  side,  called  eskers  or  osars,  owe  their  form  to  deposition  in 
the  channels  of  glacial  rivers  walled  by  ice,  but,  the  author  thinks,  com- 
monly open  above  to  the  sky.^  These  peculiar  ridges  have  a  great  develop- 
ment in  Ireland  and   Sweden,  whence  their  names  come,  and  in   Maine, 

'  Report  of  the  International  Geological  Congress,  second  session,  Boulogne,  1881,  p.  621. 
2  U.  S.  Geol.  Survey,  Third  Annual  Report,  for  1881-82,  p.  299.      Am.  Jour.  Sci.  (3),  Vol.  XXVII, 
p.  389,  May,  1884. 

^Proceedings,  Boston  Society  of  Natural  History,  Vol.  XXV,  1891,  pp.  238-242. 


180  THE  GLACIAL  LAKE  AGASSIZ. 

where  series  extending  100  to  150  miles  have  been  described  by  Prof. 
George  H.  Stone.'  They  are  well  exhibited  also  in  the  valleys  of  the  Mer- 
riniac  and  Connecticut  rivers  and  elsewhere  in  New  England,  but  are  less 
frequent  on  the  nearly  flat  expanses  which  are  drained  to  the  Laurentian 
lakes,  to  the  Upper  Mississippi,  and  to  the  Red  River  of  the  North.  Occa- 
sional plains  or  plateaus  of  gravel  and  sand,  associated  with  the  eskers, 
and,  like  them,  terminating  in  steep  escarpments  which  descend  to  adjacent 
lower  land,  were  deposited  in  broad  embayments  of  the  waning  ice  border. 

In  the  valleys  of  hilly  and  mountainous  districts,  and  on  certain  belts 
and  tracts  of  nearly  flat  areas,  the  departiu-e  of  the  ice-sheet  supplied  broad 
flood-plains  of  gi-avel,  sand,  and  clay,  brought  by  the  waters  of  the  glacial 
melting  and  of  the  accompanying  abundant  rains.  These  deposits,  when 
inclosed  in  valleys,  are  named  valley  drift,  and  are  seen  to  slope  with  the 
present  sti-eams,  but  often  somewhat  more  rapidly ;  and  they  continue  along 
the  coiu-se  of  the  larger  rivers  to  the  sea  or  to  the  areas  of  lakes  that  were 
pent  up  against  the  receding*  ice-sheet,  and  there  form  deltas  and  farther  off- 
shore sediments.  Since  the  departure  of  the  ice,  river  erosion  has  carved 
the  valley  drift  into  terraces,  and  the  streams  now  flow  far  below  their 
levels  of  the  closing  poi'tion  of  the  Ice  age. 

A  very  fine  variety  of  the  valley  di-ift,  especially  where  it  contains  some 
glacially  comminuted  rock  flour  from  calcareous  formations,  is  called  loess. 
In  the  Mississippi  and  Missouri  valleys  and  on  the  Rhine  this  deposit  is 
clearly  in  large  part  of  glacial  origin,  being  du-ectly  supplied  from  the  ice 
melting;  but  veiy  similar  fluvial  beds  are  now  being  formed  by  the  Nile 
and  were  formerly  spread  in  great  thickness  by  the  rivers  of  China,  where 
the  origin  of  the  silt  is  referable  wholly  or  chiefly  to  subaerial  denudation. 
The  alluvium  derived  from  erosion  of  the  diift  sheet  and  deposited  by  the 
Red  River  along-  its  valley  after  Lake  Agassiz  was  drained  away  resembles 
the  loess  in  fineness,  in  its  occasionally  inclosing  fresh- water  and  land  shells, 
and  in  containing  here  and  there  small  calcareous  concretions. 

'  Proceedings,  Boston  Society  of  Natural  History,  Vol.  XX,  1880,  pp.  430-469,  with  map.  Proc, 
Am.  Assoc,  for  Adv.  of  Science,  Vol.  XXIX,  for  1880,  pp.  510-519,  with  map.  Am.  Jour.  Sci.  (3),  Vol. 
XL,  pp.  122-144,  Aug.,  1890. 


TRACTS  OF  GRAVEL  AND  SAND.  181 

BELT  OF  MODIFIED  DRIFT  BETWEEN  ST.  PAUL  AND  WINNIPEG. 

Modified  drift,  consisting  of  stratified  gravel  and  sand,  with  local  de- 
posits of  clay,  overlies  the  bed-rocks  and  the  till,  and  generally  forms  the 
surface,  on  an  extensive  area  about  the  southwest  part  of  the  Lake  of  the 
Woods  and  along  the  Rainy  River.  Southward  similar  deposits  cover  large 
tracts  in  Mimiesota,  reaching  to  the  lakes  at  the  sources  of  the  Mississippi 
and  to  the  Leaf  Hills,  and  thence  southeastward  to  Minneapolis  and  St. 
Paul.  The  contour  of  the  greater  part  of  these  deposits  is  flat  or  moder- 
ately undulating,  and  their  surface  varies  in  height  from  a  few  feet  to  50 
feet  or  rarely  more  above  the  adjoining  lakes  and  streams.  lu  central 
Minnesota  these  tracts  of  gravel  and  sand  have  an  elevation  that  increases 
from  south  to  north,  being  825  to  950  feet  above  sea-level  in  the  vicinity  of 
Minneapolis  and  St.  Paul,  rising  gradually  to  1,200  feet  in  the  distance  of 
about  100  miles  northwest  to  Brainerd,  and  ranging  from  1,350  to  1,500 
feet  between  the  Leaf  Hills  and  Itasca  Lake.  Thence  their  surface  sinks 
to  1,150  and  1,075  feet  in  the  vicinity  of  Rainy  River  and  the  Lake  of  the 
Woods.  West  of  this  lake,  gravel  and  sand  cover  most  of  the  country  for 
nearly  75  miles  to  the  upper  part  of  the  Roseau,  Rat,  and  Seine  rivers, 
declining  in  this  distance  to  about  900  feet  above  the  sea.  Northwestward 
these  deposits  continue  to  a  remarkable  group  of  eskers  and  small  plateaus 
of  gravel  and  sand,  between  750  and  875  feet  above  the  sea,  7  to  15  miles 
east-northeast  of  Winnipeg,  of  which  Birds  Hill,  beside  the  Canadian 
Pacific  Railway,  is  the  most  western  and   one  of  the   most  cons2)icuous. 

This  broad  belt  of  country,  characterized  by  extensive  gravel  and  sand 
deposits  overlying  the  till,  reaches  from  south-southeast  to  north-northwest 
about  400  miles.  From  Red  Lake,  in  Minnesota,  north  to  the  Rainy  River, 
the  Lake  of  the  Woods,  and  the  vicinit}'  of  Winnipeg,  it  lies  within  the 
area  of  Lake  Agassiz.  On  each  side  this  belt  is  bordered  by  areas  of 
nearly  the  same  general  elevation,  which  have  mostly  a  surface  of  till ;  and 
it  is  to  be  remarked  that  the  heights  of  the  tracts  of  modified  di-ift  and  till 
are  alike  determined  by  that  of  the  underlying  rocks  on  which  these  super- 
ficial deposits  are  spread  as  a  sheet  of  slight  depth  in  comparison  with  the 
gradual  change  in  then-  elevation.  The  drift  sheet  on  this  belt,  including 
both  the  sand  and  gravel  and  tlie  underlying  deposits  of  till,  jjrobabh' 


182  THE  GLACIAL  LAKE  AGASSIZ. 

vai-ies  in  its  average  thickness  from  50  to  150  feet,  while  its  central  portion 
rises  400  to  600  feet  above  its  south  and  north  ends.  Though  the  greater 
part  of  both  the  modified  drift  and  till  have  only  slight  undulations,  the 
former  being  often  nearly  flat  and  the  latter  moderately  uneven,  other  por- 
tions are  crossed  by  moraines  wliich  have  a  prominently  knoUy  and  hilly 
contour,  rising  usually  25  to  75  feet,  or  occasionally  100  to  200  feet,  and 
in  the  Leaf  Hills  100  to  350  feet,  above  the  adjoining  country.  In  some 
places  the  belts  of  morainic  hills,  consisting  chiefly  of  till,  with  abundant 
bowlders,  are  bordered  on  one  side  by  tracts  of  stratified  gravel  and  sand 
which  slope  slowly  downward  from  them  and  are  merged  in  the  extensive 
plains  or  moderately  undulating  areas  of  this  modified  drift,  showing  that 
a  part  of  the  gravel  and  sand  was  brought  by  streams  that  descended  from 
the  ice-sheet  dming  the  time  of  accumulation  of  its  moraines.  Besides 
these  overwash  slopes  (if  modified  drift,  the  morainic  belts  often  include 
kames,  or  knolls,  hillocks,  and  short  ridges  of  sand  and  gravel. 

During  the  rapid  melting  of  the  ice  in  its  times  of  retreat  between 
successive  moraines  the  glacial  streams  attained  their  greatest  extent  and 
volume,  and  brought  proportionately  extensive  deposits  of  modified  drift, 
spreading  it  mainly  in  plains  or  moderately  undulating  tracts  beyond  the 
ice  margin,  but  here  and  there  leaving  long  esker  ridges  of  gravel  and 
sand,  which  were  formed  in  their  channels  between  walls  of  ice.     The  dis- 
tribution of  the  modified  di-ift  thus  found  upon  large  tracts  along  a  broad 
belt  from  St.  Paul  to  Winnipeg,  while  it  is  very  scantily  developed  *on  a- 
still  wider  region  of  Minnesota,  North  Dakota,  and  Manitoba  southwest  of 
this  belt,  and  likewise  is  scanty  or  wanting  on  its  northeast  side  in  northern 
Minnesota  and  about  Rainy  Lake  and  the  northeast  and  north  portions  of 
the  Lake  of  the  Woods,  seems  to  be  attributable  to  converging  slopes  of 
the  surface  of  the  ice-sheet  and  the  consequent  convergence  of  its  cuirents, 
which  brought  an  unusual  amount  of  euglacial  drift  into  the  ice  along  this 
belt,  and  by  which  also  the  streams  produced  in  its  melting  were  caused  to 
flow  thither  from  extensive  areas  of  the  ice  on  the  east  and  west.     The 
o-lacial  strise  of  these  adjoining  areas  show  that  on  the  east  the  course  of 
the  motion  and  the  descent  of  the  surface  of  the  ice-sheet  were  from  north- 
east to  southwest,  but  that  on  the  west  the  glacial  current  moved  and  the 


BSKEES  IX  MANITOBA.  183 

ice  surface  sloped  toward  the  southeast.  On  the  east  drift  Hmestone  is 
absent  or  very  rare,  because  no  limestone  formations  were  crossed  within 
several  hundred  miles  by  that  part  of  the  ice-sheet;  liut  on  the  west  the 
drift,  consisting  chiefly  of  a  thick  sheet  oi  till,  contains  much  fine  limestone 
detritus,  sand  and  gravel,  and  frequent  bowlders  of  limestone,  borne  south- 
eastward from  Manitoba  over  the  Archean  area  of  the  southwest  part  of 
the  Lake  of  the  Woods,  of  Rainy  River,  and  of  northern  and  central  Min- 
nesota. In  the  same  directions  with  the  slopes  of  the  ice  surface,  which 
are  known  from  the  courses  of'  the  glacial  striae  and  the  transportation  of 
the  drift,  tlie  streams  of  the  glacial  melting  flowed  convergently  from  the 
east  and  west,  from  the  ice  over  northern  Minnesota  and  eastern  Manitoba 
on  one  side,  and  from  that  over  the  Red  River  Valley  and  western  Mani- 
toba on  the  other,  toward  this  belt  of  plentiful  superficial  deposits  of  gravel 
and  sand. 

Dr.  George  M.  Dawson^  and  Dr.  A.  C.  Lawson^  have  referred  these 
gravel  and  sand  beds,  observed  by  them  only  about  the  south  part  of  the 
Lake  of  the  Woods  and  along  Rainy  River  to  the  mouth  of  Rainy  Lake, 
within  the  area  of  Lake  Agassiz,  to  lacustrine  action.  That  explanation, 
however,  is  inconsistent  with  the  restriction  of  the  deposits  to  a  small  part 
of  the  area  of  this  glacial  lake,  and  with  their  continuation  far  to  the  south, 
beyond  the  limit  of  the  lake  and  upon  a  district  that  rises  in  part  consider- 
ably above  it;  while  their  distribution  and  character  show  that  instead 
they  were  derived,  as  indicated,  directly  from  the  ice-sheet  and  its  inclosed 
drift.  They  will  be  again  noticed  in  coimection  with  the  history  of  the 
formation  of  Lake  Agassiz,  to  be  considered  in  the  next  chapter. 

BIRDS  HILL  AND  OTHER  ESKERS  IN  MANITOBA. 

Prominent  eskers  begin  at  Birds  Hill,  the  first  station  of  the  Canadian 
Pacific  Railway  northeast  of  Winnipeg,  from  which  it  is  7  miles  distant,  and 
extend  thence  7  or  8  miles  east-noi-theast  and  an  equal  distance  southeast, 
as  shown  in  the  sketch  map  forming  fig.  9.  The  southern  and  southeastern 
portion  of  this  group  comprises   many  low  ridges  of  gravel  and  sand  5 

'  Report  on  the  Geology  and  Resonrces  of  the  Region  iu  the  Vicinity  of  the  Forty-ninth  Parallel, 
pp. 203-218. 

-Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  I,  for  1885,  pp.  131  and  139 
CC;  Vol.  Ill,  for  1887,  pp.  174-176  F. 


184 


THE  GLACIAL  LAKE  AGASSIZ. 


to  15  feet  liigli,  trending  from  northwest  to  southeast;  also  somewhat 
rounded  mounds,  as  Oak  Hummock,  in  the  southeast  quarter  of  section  12, 
township  11,  range  4  east,  which  rises  about  30  feet  above  the  adjoining 
country,  with  its  top  approximately  810  feet  above  the  sea;  and  occasion- 
ally a  massive  and  conspicuous  hill,  as  Moose  Nose,  in  sections  29  and  30, 
township  11,  range  5  east,  which  projects  60  feet  above  the  average  of 
the  nearly  flat  country  around  it,  rising  to  about  840  feet  above  the  sea. 


Fig.  9. — Map  of  Birds  Hill  and  its  vicinity.    Scale,  3  miles  to  an  inch. 

Toward  the  north,  in  sections  35  and  36,  township  11,  range  4  east,  and 
again  from  section  2,  township  12,  range  4  east,  through  a  distance  of  4 
miles  east-southeast  to  section  9,  township  12,  range  5  east,  these  deposits 
of  gravel  and  sand  form  plateaus  a  half  mile  to  1  mile  wide,  trending  from 
west  to  east,  elevated  820  to  850  feet  above  the  sea  and  40  to  60  or  75  feet 
above  the  adjoining  low  land,  which  on  the  north  is  a  spruce  and  tamarack 
swamp  about  1  mile  wide  and  4  miles  long  from  east  to  west.     Next  to  the 


SECTION  OF  BIRDS  HILL.  185 

north,  these  eskers  again  rise  in  plateaus,  ridg-es,  and  hills  in  sections  19  to 
22,  township  12,  range  5  east,  culminating  in  Grriffiths  Hill,  in  the  northeast 
quarter  of  section  19,  about  875  feet  above  the  sea,  or  a  little  more  than 
100  feet  above  the  railway,  2  miles  distant  on  the  west.  This  whole  group 
of  elevations  is  composed  of  gi-avel  and  sand,  irregularly  bedded,  which 
appear  to  be  deposits  formed  near  the  mouths  of  glacial  rivers  where  they 
flowed  between  walls  of  ice,  and  were  here  and  there  divided  by  ice  islands, 
whose  melting  left  these  hills,  ridges,  and  plateaus  bounded  by  moderately 
steep  slopes  and  separated  by  intervening  depressions.  With  the  comple- 
tion of  the  melting  of  the  ice  about  and  beneath  these  deposits  they  sank 
to  the  bottom  of  Lake  Agassiz,  here  about  500  feet  deep;  and  tlie  infre- 
quent bowlders  that  are  found  scattered  upon  their  surface  were  dropped 
from  floating  ice.  Toward  the  north,  west,  and  southwest  they  are 
bounded  by  the  flat  plain  of  the  Red  River  Valley,  750  to  760  feet  above 

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Fig.  10. — Section  of  Birds  Hill.    Horizoutal  acale,  oiie-fourtli  mile  to  an  inch. 

the  sea,  while  toward  the  east  and  southeast  they  are  connected  with 
plains  and  undulating  tracts  of  gravel  and  sand  which  reach  M'ith  slow 
and  gradual  ascent  to  the  Lake  of  the  Woods  and  into  Minnesota. 

An  instructive  section  of  Birds  Hill  (fig.  10)  has  been  made  in  the 
excavation  of  its  gravel  and  sand  for  railway  ballast.  This  massive  esker 
extends  from  the  railway  station  about  1  mile  east-southeast  and  thence  a 
half  mile  southeast,  beyond  which  it  is  connected  b}-  a  low  ridge  with  the 
plateau  of  sections  35  and  36,  township  11,  range  4  east.  Its  width  is  a 
quarter  to  a  half  of  a  mile ;  and  its  maximum  height,  one-third  to  two-thirds 
of  a  mile  from  the  station,  is  45  to  50  feet  above  the  railwa}^  and  the  flat 
plain  that  extends  thence  west.  The  elevation  of  Birds  Hill  station  is  759 
feet,  and  of  the  crest  of  this  hill  805  to  810  feet,  above  the  sea.  It  has  a 
broadly  rounded  top,  with  gentle  slopes  on  all  sides.  Along  its  northern 
slope  an  excavation  reaches  three-fourths  of  a  mile,  varj-ing-  in  width  from 


186  THE  GLACIAL  LAKE  AGASSIZ. 

10  to  25  rods  and  in  depth  from  10  to  30  feet.  The  top  of  the  excavation 
is  about  20  feet  below  the  crest  of  the  hill.  As  thus  exposed  to  view,  the 
greater  part  of  this  deposit  is  seen  to  be  gravel,  much  of  which  is  very 
coarse,  containing  pebbles  and  rock  fragments  of  all  sizes  up  to  IJ  feet  in 
diameter,  many  of  the  smaller  being  Avell  rounded,  but  the  larger  mostly 
angular,  with  only  slight  marks  of  water  wearing.  In  some  portions  near 
the  west  end  of  this  sectioii  no  interbedding-  of  coarser  and  finer  layers  of 
the  ton-ential  esker  gravel  is  noticeable  for  10  feet  or  more  vertically,  the 
spaces  between  the  larger  stones  and  cobbles  being  filled  with  finer  gravel 
and  sand.  Embedded  in  this  coarse  gravel  on  the  south  side  of  the  exca- 
vation I  noted  a  mass  of  ordinary  till,  unstratified  bowlder-clay,  inclosing 
gravel  and  bowlders  in  a  solid  matrix  of  somewhat  sandy  clay,  wholly 
bounded  by  definite  but  irregular  outlines,  its  dimension  vertically  being 
about  10  feet  and  its  length  20  feet.  No  other  mass  of  till,  of  either  small 
or  large  size,  was  observed  in  this  entire  section.  It  probably  was  derived 
from  the  di-ift  that  was  contained  within  the  ice-sheet  and  finally  overspread 
its  surface  when  the  greater  part  of  the  thickness  of  the  ice  was  melted. 
From  a  sheet  of  drift  thus  deposited  on  the  ice  that  formed  the  bank  of  the 
glacial  river  this  mass  may  ha^^e  fallen  into  its  channel.  The  eastern  half 
of  the  section  includes  much  fine  gravel  and  sand  irregularly  interbedded, 
and  along  a  considerable  extent  there  the  south  side  of  the  excavation,  from 
10  to  20  feet  below  its  top,  is  clear  sand.  Paleozoic  limestones  make  up 
about  three-fourths  of  the  gravel,  the  remainder  being  Archean  granites, 
pfneiss,  and  schists.  Some  two  hundred  bowlders  were  found  scattered 
upon  the  area  of  the  excavation;  and  they  occur  with  nearly  the  same  fre- 
quency on  other  portions  of  this  northern  slope  of  the  hill,  but  are  rarely 
found  on  its  top  and  southern  slope.  They  vary  in  size  from  2  to  8  or  10 
feet  in  length;  nearly  all  are  Arcliean,  but  a  few  of  Paleozoic  limestone, 
up  to  5  feet  in  length,  were  observed.  None  was  seen  inclosed  within  the 
gravel  and  sand  of  the  esker,  and  the  workmen  informed  me  that  they 
occur  only  on  or  near  the  surface.  This  hill  was  covered  by  Lake  Agassiz, 
and  its  bowlders  were  doubtless  di-opped  or  stranded  from  bergs  and  floes 
on  this  lake  before  the  border  of  the  ice-sheet  had  retreated  from  the 
vicinity.     Indeed,  the  occurrence  of  the  bowlders  chiefly  on  the  northern 


SECTION  OF  BURNS  EIDGE.  187 

slope  seems  to  indicate  that  they  were  mostly  sti'anded  there  while  ice  yet 
remained  beneath  this  deposit  and  prevented  its  entire  submergence  in  the 
lake.  The  thickness  of  this  esker  is  at  least  nearly  100  feet;  for  a  well  45 
feet  deep,  dug  at  the  bottom  of  the  excavation,  was  wholly  in  the  same 
formation  of  gravel  and  sand.  It  is  thus  known  to  extend  considerably 
below  the  level  of  the  Red  River  Valley  plain,  which  consists  of  fluvial 
and  lacustrine  clay  underlain  at  a  slight  depth  by  till.  A  section  across 
the  esker  and  plain  (fig.  10)  would  show  till  abutting  upon  the  edge  of  the 
gravel  and  sand,  indicating  that  both  the  stratified  esker  and  the  upper 
part  of  the  till  were  formed  from  englacial  drift. 

Smaller  esker  deposits  were  observed  in  townships  12  and  13,  range  1 
east,  10  to  20  miles  northwest  of  Winnipeg.  Beginning  about  3  miles  east 
of  Rosser,  a  narrow  and  occasionally  interrupted  belt  of  esker  gravel  and 
sand,  with  frequent  bowlders  scattered  on  the  surface,  extends  northwest 
diagonally  across  sections  10,  16,  and  20,  the  northeast  corner  of  section 
19,  and  the  southwest  part  of  section  30,  township  12,  and  thence  west- 
ward through  section  25  of  the  next  township.  Its  highest  portions  rise 
10  to  25  feet  above  the  depressions  of  the  moderately  undulating  surface 
of  till  on  each  side  and  are  800  to  810  feet  above  the  sea.  Along  a  distance 
of  about  a  third  of  a  mile  in  section  30  it  has  the  form  and  character  of  an 
ordinary  beach  ridge  and  is  destitute  of  bowlders.  A  similar  low  esker 
crosses  sections  12  and  14,  township  13,  trending  from  southeast  to  north- 
west; and  others  occur  in  the  vicinity  of  the  Grosse  Isle,  a  name  applied 
to  poplar  groves  in  sections  17  and  18  of  this  township  and  in  sections  12 
and  13  of  the  next  west. 

From  the  east  part  of  the  Grrosse  Isle  a  notable  esker,  known  as  Burns 
Ridge,  runs  north-northwestward  across  sections  30  and  31,  township  13, 
range  1  east.  Five  miles  west  of  Stonewall  a  section  of  this  little  beach- 
like ridge  was  made  in  section  30  by  the  original  line  of  the  Canadian 
Pacific  Railway,  which  was  abandoned  for  the  more  southern  route  by  way 
of  Winnipeg.  The  esker  is  cut  to  a  depth  of  8  feet  by  the  railway  and  to 
12  feet  in  an  excavation  on  the  south  side  of  the  railway  grade.  A  well 
in  the  lowest  part  of  this  excavation  goes  4  feet  deeper,  to  a  total  of  16 
feet  below  the  crest  of  the  ridgfe.     The  entire  section  consists  of  stratified 


188  THE  GLACIAL  LAKE  AGASSIZ. 

gravel  aud  sand,  extending  8  feet  above  and  at  least  as  far  below  the  gen- 
eral level  of  the  adjoining  surface,  and  the  visible  width  of  the  deposit  is 
about  30  rods.  How  much  deeper  it  may  extend,  perhaps  with  increasing 
width,  is  undetermined.  Its  gravel,  which  is  nearly  all  limestone,  contains 
jDebbles  up  to  6  inches  in  diameter.  No  bowlders  occur  in  this  excavation, 
and  they  are  rare  upon  the  surface  of  this  and  other  such  comparatively 
broad  and  high  j^ortions  of  this  esker,  none  being  sometimes  seen  along  a 
distance  of  several  rods;  but  in  its  narrower  and.  slightl}^  lower  portions,  as 
traced  in  its  somewhat  crooked  course  northward  tlu'ough  the  next  1  h  miles, 
it.  often  is  found  to  be  sprinkled  with  frequent  bowlders  up  to  3  or  4  feet  in 
diameter,  mostly  Archean.  They  appear  to  have  been  stranded,  as  at  Birds 
Hill,  immediately  after  the  ice  walls  inclosing  the  esker  were  melted,  or 
even  during  that  process,  and  before  the  luelting  of  the  ice  under  this 
gravel  and  sand  allowed  the  'n'Tater  of  Lake  Agassiz  to  submerge  the  more 
massive  portions  of  the  ridge.  Only  a  small  depth  of  water,  probably  not 
more  than  30  or  50  feet  at  the  most,  would  be  required  for  this;  and  after- 
ward the  melting  of  the  underlying  ice  gave  to  the  lake  here  a  dejith  of 
fully  500  feet.  Farther  to  the  north  the  esker  sinks  or  is  mei'ged  in  the 
moderately  undulating  till  which  there  forms  the  surface.  The  crest  of 
this  peculiar  ridge,  approximately  800  to  805  feet  above  the  sea,  undulates 
3  to  5  feet  within  short  distances,  not  showing  so  much  unifonnitj^  in  eleva- 
tion and  directness  in  its  coiu'se  as  are  characteristic  of  beach  ridges;  and  it 
is  the  only  instance  observed  in  all  mj  exploration  of  Lake  Agassiz  where 
a  gi-avel  formation  nearly  resembling  a  beach  bears  bowlders  oia  its  surface. 
Not  a  single  bowlder  has  been  anywhere  found  on  or  within  the  beaches  of 
this  lake;  nor  have  eskers  like  the  Birds  Hill  group  or  like  these  of  smaller 
size  and  more  stream-like  courses  been  observed  by  me  in  an}-  other  part 
of  this  lacustrine  area,  excepting  the  vicinit}^  of  Red  Lake,  in  Minnesota. 
But  eskers  doubtless  exist  here  and  there  tlu-oughout  the  belt  of  modified 
di'ift  that  extends  upon  this  area  from  Red  Lake  by  the  Lake  of  the  Woods 
to  Birds  Hill  and  Burns  Ridge,  and  probably  they  continue  north-north- 
westerly upon  the  country  between  Lake  AVinnipeg  and  Shoal  Lake. 


MODIFIED  DRIFT  FORMING  DELTAS.  189 

PEOPORTION  OF    MODIFIED    DRIFT    SUPPLIED   TO    THE    DELTAS  OF    LAKE  AGASSIZ. 

Extensive  contributions  of  iiuvial  silt  were  received  in  Lake  Agaseiz 
from  the  englacial  drift  of  the  retreating  ice  both  on  the  east  and  west; 
and  these  deposits  agree  with  the  terminal  moraines  of  that  region  in  indi- 
cating that  against  this  great  glacial  lake  the  ice  was  melted  back,  faster 
than  on  the  adjoining  land  areas.  On  the  eastern  side  of  Lake  Agassiz 
only  the  Buffalo  and  Sand  Hill  rivers  brought  in  noteworthy  deltas,  but 
several  other  tributaries  from  the  east  are  at  the  present  time  larger  than 
these.  No  topographic  or  other  now  existing  causes  for  this  difference  are 
discoverable,  and  we  are  left  to  the  inference  that  during  the  vicissitudes 
of  the  glacial  recession  exceptionally  large  streams  poured  down  from  the 
ice  surface,  laden  with  its  drift,  to  these  deltas.  Similar  conditions  seem 
also  to  have  been  largely  efficient  in  producing  the  four  great  deltas  which  I 
have  examined  on  the  western  side  of  Lake  Agassiz,  namely,  the  Sheyenne, 
Elk  Vallev,  and  Pembina  deltas  in  North  Dakota,  and  that  of  the  Assini- 
boine  in  Manitoba.  Each  of  these  demonstrably  contains  much  tribute  of 
modified  drift;  that  is,  of  drift  brought  directly  from  the  ice  by  the  rivulets, 
brooks,  and  rivers  formed  in  its  melting. 

It  will  be  especially  instructive  to  notice  the  Assiniboine  delta  of  Lake 
Agassiz  and  attempt  to  estimate  its  proportion  of  modified  drift  as  distin- 
guished from  the  alluvium  of  ordinary  river  erosion.  This  remarkable 
delta  of  gravel  and  sand  covers  an  area  of  about  2,000  square  miles  and 
has  an  estimated  average  depth  of  at  least  50  feet.  Its  volume  is  about  20 
cubic  miles,  so  that  it  exceeds  the  combined  capacity  of  the  Qu'Appelle 
Valley,  which  was  the  outlet  of  the  glacial  Lake  Saskatchewan,  and  of  the 
Assiniboine  Valley  from  the  movith  of  the  Qu'Appelle  to  this  delta.  Each 
of  these  valleys  has  an  average  width  of  about  1  mile,  and  their  depth 
probably  averages  250  feet  along  their  extent  of  about  350  miles,  being 
eroded  in  drift  and  the  underlying  soft  Fort  Pierre  shales.  This  was  doubt- 
less a  preglacial  watercourse,  which,  like  the  Pembina  and  Minnesota 
valleys,  became  only  partly  filled  with  drift.  Much  of  the  erosion  of  the 
iipper  Qu'Appelle  Valley  during  the  departure  of  the  ice-sheet  was  effected 
by  its  glacial  river  while  it  emptied  into  the  Lake  Souris,  and  probably  the 
lower  valley  and  that  of  the  Assiniboine  were  filled  on  the  average  only 


190  THE  GLACIAL  LAKE  AGASSIZ. 

to  the  extent  of  a  third  or  half  of  their  depth  by  the  glacial  drift.  The 
erosion  of  the  valley,  therefore,  must  have  fallen  far  short  of  supph'ing- 
the  material  of  the  Assiniboine  delta,  not  to  mention  the  fine  silt  and 
clay  which  were  carried  into  the  lake  l^eyond  the  gravel  and  sand  delta 
and  may  be  of  equal  volume.  Probably  at  least  half  of  these  lacustrine 
deposits  were  modified  drift  brought  down  by  streams  from  the  melting 
ice-sheet  on  the  upper  Assiniboine  l)asin,  north  of  the  mouth  of  the  Qu'Ap- 
pelle,  and  swept  forward  by  the  strong  current  of  the  river  until  it  reached 
Lake  Agassiz. 


INFLUENCE    OF    ADJOINING    LAKES    OR    THE    SEA    ON    THE    DEPOSI- 
TION   OF    THE    DRIFT. 

From  Nantucket  and  Cape  Cod  northeastward  the  ice-sheet,  at  its 
greatest  extent  and  dui'ing  a  considerable  part  of  its  time  of  recession, 
terminated  in  the  ocean.  In  the  interior  of  the  continent,  too,  it  was 
bounded  during  its  recession  l)y  vast  lakes  filling  the  basins  that  are  now 
partly  occupied  by  the  great  lakes  of  the  St.  Lawrence,  Nelson,  and  Mac- 
kenzie rivers.  During  all  my  examination  of  the  shore-lines,  deltas,  and 
bed  of  Lake  Agassiz  I  have  carefully  studied  the  effects  attributable  to 
the  influence  of  this  lake  on  the  deposition  of  the  di'ift,  comparing  its  area, 
the  valley  of  the  Red  River  of  the  North,  with  other  portions  of  Minne- 
sota, South  and  North  Dakota,  and  Manitoba,  which  had  a  land  sm-face 
dm'ing  the  departure  of  the  ice.  Other  glacial  lakes  of  smaller  size  in 
these  States  and  this  Canadian  province  have  also  come  under  my  obser- 
vation, besides  portions  of  the  drift  deposited  in  the  glacial  precursors  of 
the  Laurentian  lakes;  and  on  the  Atlantic  Coast  I  have  made  a  detailed 
examination  of  the  marine  drift  of  southeastern  New  Hampshire.  The 
more  southern  parts  of  the  New  England  seaboard'which  I  have  similarly 
examined,  including  the  coast  from  Boston  to  Plymouth,  Cape  Cod,  Nan- 
tucket, Marthas  Vineyard,  the  Elizabeth  Islands,  Block  Island,  and  Long 
Island,  appear  to  me  to  have  stood  at  their  present  height  or  somewhat 
hisfher  durino:  the  maximum  extension  and  the  recession  of  their  bi'oad 
eastern  lobe  of  the  ice-sheet. 


DEPOSITION  OF  THE  ENGLACIAL  DRIFT.  191 

Upon  all  the  areas  thus  studied  by  me  where  the  ice-sheet  was  bor- 
dered by  great  lakes  or  the  sea,  tracts  of  stratified  sediments,  as  deltas  of 
gravel,  sand,  and  silt,  and  somewhat  more  extensive  deposits  of  finer  silt 
and  clay,  are  found,  and  their  distribution  shows  them  to  have  been  brought 
into  these  bodies  of  water  chiefly  by  rivers  flowing  from  the  melting  ice. 
But  a  large  portion  of  the  englacial  and  superglacial  drift,  corresponding  to 
that  which  fell  as  wholly  unstratified  till  on  land  areas,  was  received  from 
the  receding  ice  into  these  lakes  or  the  sea  Avith  little  change,  being  allowed 
to  fall  to  their  bottom  only  very  slightly  modified  by  water  action.  Within 
the  area  of  Lake  Agassiz  and  the  other  associated  glacial  lakes,  very  exten- 
sive tracts,  probably  half  or  a  larger  part  of  their  whole  extent,  have  a 
surface  of  till,  which  difters  from  its  characters  on  the  adjoining  tracts  that 
were  land  during  the  ice  retreat  in  having  usually  slight  traces  of  stratifi- 
cation within  the  5  to  15  feet  of  the  upper  and  englacial  till,  and  in  having 
a  more  smooth  and  even  contour. 

Bowlders,  gravel,  sand,  and  clay  are  mingled  in  this  englacial  till  in 
the  same  proportion  as  on  the  country  outside  these  glacial  lakes.  There 
was  generally  no  noteworthy  transportation  of  bowlders  or  othei  drift 
by  ice  floes  or  bergs  on  these  lakes ;  nor  was  the  fine  clayey  part  of  the 
englacial  drift  washed  away  in  any  noteworthy  amount  from  the  sub- 
merged and  melting  and  receding  ice  margin  by  wave  action,  which  would 
have  covered  the  till  in  front  of  the  ice-sheet  with  beds  of  silt.  Instead, 
the  englacial  and  finally  superglacial  di'ift  that  escaped  the  stream  erosion 
of  the  drainage  from  the  glacial  melting  sank  through  the  water  to  the 
bottom  as  the  ice  gradually  withdi'ew,  and  exhibits  essentially  the  same 
characters  as  on  areas  that  were  land,  excepting  its  usually  obscure  traces 
of  stratification  and  its  smoother  surface. 


CHAPTER    V. 
HISTORY   OF   LAKE   AGASSIZ. 

TWO  CLASSES   OF   PLEISTOCENE   LAKES. 

Among  the  most  important  geologic  records  of  the  Pleistocene  period 
in  America  are  the  sediments  and  shore-lines  of  former  lakes  of  great  extent 
which  are  now  represented  by  lakes  that  occupy,  excepting  within  the 
basin  of  the  St.  Lawrence,  only  a  small  part  of  their  ancient  area.  Lake 
Bonneville,  in  the  basin  of  Great  Salt  Lake,  Utah,  and  Lake  Lahontan, 
in  the  basin  of  the  Humboldt  River  and  Pyramid  Lake,  Nevada,  are  con- 
spicuous examples  of  one  class  of  these  Pleistocene  lakes,  formed  by 
increased  rainfall,  where  now  an  arid  climate  limits  the  lakes  to  small  areas, 
with  their  surface  far  below  the  watersheds  across  which  they  would  out- 
flow to  the  sea.  These  are  south  of  the  glaciated  area  of  the  continent, 
but  they  appear  to  have  owed  their  existence  to  the  changes  of  climate 
by  which  the  ice-sheet  of  the  Glacial  period  was  formed.  Lake  Agassiz 
belongs  to  another  class  of  these  lakes,  caused  directly  by  the  barrier  of 
the  ice-sheet  where  this  was  accumulated  on  a  noi'thwardly  sloping  laud 
surface.  Such  glacial  lakes  were  developed  on  a  vast  scale  in  the  basins 
of  Lake  Winnipeg  and  the  Laurentiau  lakes  during  the  recession  of  the 
ice  border,  when  it  was  being  gradually  melted  away  by  a  warmer  climate  ; 
and  it  is  also  evident  that  many  small  lakes  of  the  same  kind  then  flowed 
southward  over  the  lowest  points  of  the  present  watersheds.  Examples  of 
this  class  now  existing  are  the  little  Meijelen  See,  pent  up  in  a  tributary 
valley  on  the  east  side  of  the  Great  Aletsch  glacier  in  the  Alps,  and  similar 
ice-dammed  lakelets  in  Greenland. 

LAKES  BONNEVILLE,  LAHONTAN,  AND  OTHERS  IN  THE  GREAT  BASIN. 

Twice  during  the  climatic  changes  of  the  Glacial  and  post-Glacial 
periods,  Lake  Bonneville,  described  by  Gilbert,^  and  Lakes  Lahontan  and 

'Lake  Bonneville.     By  6.  K.  Gilbert.     Monographs  of  the  U.  S.  Geol.  Survey,  Vol.  I. 
192 


LAKES  BONNEVILLE  AND  LAHONTAN.  193 

Mono,  described  by  Russell/  have  risen  nearly  or  quite  to  overflowing. 
The  climate  of  the  Great  Basin  of  interior  di-ainage,  which  comprises  the 
areas  of  these  lakes,  was  marked  at  these  times  by  considerably  greater 
humidity  than  now,  though  to  less  degree  than  the  present  climate  of  the 
eastern  half  of  the  United  States.  The  humid  epochs  were  divided  by 
■a  long  interval  of  aridity,  in  which,  as  Gilbert  and  Russell  have  shown, 
the  lakes  were  perhaps  wholly  evaporated,  their  soluble  salt  and  alkaline 
mineral  matter  becoming  intermingled  and  covered  with  playa  silts,  so  that 
it  could  not  be  redissolved  by  the  water  of  the  lakes  during  their  second 
rise,  which  therefore  may  have  been  nearly  fresh. 

Lake  Bonneville,  the  largest  one  of  the  many  lakes  which  were  formed 
during  the  Pleistocene  period  in  the  Great  Basin,  covered  at  its  maximum 
stage  an  area  of  19,750  square  miles,  lying  mostly  in  northwestern  Utah, 
but  extending  also  into  the  borders  of  Nevada  and  Idaho.  It  was  about 
ten  times  as  large  as  its  present  representative,  Great  Salt  Lake,  which, 
having  a  mean  height  of  4,208  feet  above  the  sea,  lies  1,000  feet  below  the 
highest  of  the  ancient  shore-lines.  The  maximum  depth  of  the  Pleistocene 
lake  was  about  1,050  feet,  while  that  of  Great  Salt  Lake,  in  its  range  from 
the  lowest  to  the  highest  stage  within  the  past  forty  years,  is  from  36  to  49 
feet.  The  hydrographic  basin  of  Lake  Bonneville  comprised  a  fourth  part 
of  the  Great  Basin,  whose  total  area  is  estimated  to  be  210,000  square  miles; 
almost  another  quarter  was  tributary  to  the  companion  Lake  Lahontan, 
which  attained  an  extent  of  8,422  square  miles,  occupying  a  very  irregular 
tract  of  interlocking  valleys  among  mountain  ranges  in  western  Nevada; 
and  the  remaining  half  of  this  arid  region  held  some  twenty-five  smaller 
lakes,  much  exceeding,  however,  the  saline  lakes  and  playas  to  which  they 
are  now  reduced. 

The  first  great  i-ise  of  Lake  Bonneville,  lifting  its  level  to  within  90 
feet  of  the  lowest  point  of  the  inclosing  watershed,  is  recorded  by  numer- 
ous beaches,  marking  the  oscillations  of  the  lake  level  under  the  varying- 
influence  of  secular  climatic  changes,  and  by  a  thick  deposit  of  yellow 

'  Geological  History  of  Lake  Lahontau.  By  I.  C.  Russell.  Mouograplis  of  the  U.  S.  Geol.  Survey, 
Vol.  XI.  Quaternary  History  of  Mono  Valley,  California.  By  i.  C.  Russell.  Eighth  Annual  Report 
of  the  XJ.  S.  Geol.  Survey. 

MON  XXV 13 


194  THE  GLACIAL  LAKE  AGASSIZ. 

clay.  A  long  interlacustrine  epoch  is  known  by  overlying-  alluvial  gravel 
and  sand.  The  second  rise  of  the  lake  reached  the  level  of  overflow 
apparently  after  the  water  surface  had  been  long  held  within  5  to  20  feet 
below  that  level,  forming  a  widely  spread  deposit  of  white  marl  and  the 
well-defined  highest  beach  ridges  and  eroded  cliifs,  which  Gilbert  names 
the  Bonneville  shore-line.  The  time  required  for  the  great  amount  of  wave 
work  at  this  level  would  be  made  possible  by  long-continued  underground 
drainage  from  the  lake  tlu'ough  the  alluvial  deposit  of  Cache  Valley,  over 
which  a  slightly  higher  rise  of  the  lake  finally  gained  a  superficial  outflow 
to  the  Columbia  River,  and  then  rapidly  cut  a  channel  375  feet  deep  in  the 
alluvium  to  a  sill  of  limestone.  At  this  lower  level,  marked  b}"  the  Provo 
shore-line  and  deltas,  the  lake,  was  held  for  a  long*  time,  perhajDs  occasion- 
ally interrupted  by  diy  climate  and  fall,  of  the  water  too  low  to  maintain 
its  outlet. 

Glaciers  descending  the  canyons  on  the  w'est  front  of  the  Wasatch 
Range  attained  their  maximum  extent,  pushing  their  moraines  into  Lake 
Bomieville,  during  the  time  of  formation  of  the  Provo  shore-line.  From. 
these  moraines,  and  from  those  of  the  Sierra  Nevada  extending  into  the 
Pleistocene  area  of  Lake  Mono,  the  glaciation  of  the  Cordilleran  region  is 
known  to  have  been  contemporaneous  with  the  epochs  of  humid  climate 
and  extension  of  lakes  in  the  Great  Basin,  the  interlacustrine  epoch  being 
attended  probably  with  a  nearly  or  quite  complete  departure  of  the  glaciers 
and  ice-fields  on  the  mountains. 

LAKE    AGASSIZ    KUD    OTHER    GLACIAL   LAKES.^ 

A  glacial  lake,  according  to  my  use  of  the  term  in  this  volume  and 
elsewhere,  is  a  body  of  water  bounded  in  part  by  a  barrier  of  land  ice. 
The  lake  may  be  hemmed  in  by  a  glacier,  as  the  Merjelen  See,  or  by  a 
continental  ice-sheet,  as  Lake  Agassiz.  And  the  same  name  is  also  appli- 
cable to  the  lakelets,  wholly  bounded  by  ice,  which  are  occasionally 
formed,  attaining  a  considerable  depth  and  extent  and  appearing  in  the 
same  places  during  the  summers  of  successive  years,  on  the  sm-face  of 

'  The  following  descriptions  and  discussion  of  this  class  of  Pleistocene  lakes  were  originally  pre- 
sented in  a  paper  before  the  Geological  Society  of  America  ("Glacial  Lakes  in  Canada,"  Bulletin, 
G.  S.  A.,  Vol.  II,  pp.  243-276). 


EVIDENCES  OP  GLACIAL  LAKES.  195 

glaciers,  as  iu  the  Himalayan  Range,  or  on  an  ice-sheet,  as  observed  by 
Nordenskjold  in  Greenland. 

Very  abundant  and  extensive  development  of  glacial  lakes  attended 
the  recession  of  the  ice-sheet  in  the  northern  United  States  and  in  Canada, 
being  due  to  the  temporary  damming  of  the  waters  of  glacial  melting  and 
of  rains  on  areas  where  the  land  has  a  northward  descent.  While  the  ice- 
sheet  was  melting  away  from  south  to  north  on  such  a  slope,  free  drainage 
was  prevented,  and  a  lake  was  formed,  overflowing  across  the  lowest  point 
of  what  is  now  the  southern  watershed  of  the  basin.  Many  of  these  lakes 
were  of  small  extent  and  short  duration,  being  soon,  by  the  continued  re- 
treat of  the  ice,  merged  into  larger  glacial  lakes,  or  permitted  to  flow  away 
where  basins  sloping  northward  are  tributary  to  main  river  courses  drain- 
ing southward.  Professor  Chamberlin  has  well  written  of  these  lakes 
fringing  the  ice-sheet: 

They  vary  in  areal  extent  from  trivial  valleys  blocked  by  ice  to  the  broad 
expanses  of  the  great  basins.  If  an  attempt  were  made  to  enumerate  all  instances, 
great  and  small,  and  all  stages,  earlier  and  later,  the  list  of  localities  and  deposits 
would  swell,  not  by  scores  and  hundreds,  but  by  thousands.^ 

EVIDEISTCES  OF  GLACIAL  LAKES. 

Five  principal  evidences  of  the  former  existence  of  glacial  lakes  are 
found,  namely:  (1)  Their  channels  of  outlet  over  the  present  watersheds; 
(2)  cliffs  eroded  along  some  portions  of  the  shores  by  the  lake  waves;  (3) 
beach  ridges  of  gravel  and  sand,  often  on  the  larger  glacial  lakes  extend- 
ing continuously  through  long  distances;  (4)  delta  deposits,  mostly  gravel 
and  sand,  formed  b}'  inflowing  streams;  and  (5)  fine  sediments  spread 
widely  over  the  lacustrine  area.  A  few  words  of  general  description  may 
be  given  to  each  of  these  before  proceeding  to  notice  the  areas  of  some  of 
the  more  important  glacial  lakes  formed  by  the  waning  North  American 
ice-sheet,  and  to  trace  in  detail  the  stages  of  the  growth  of  Lake  Agassiz 
and  its  final  reduction  to  the  present  Lake  Winnipeg. 

Outlets. — Among  the  e^adences  of  glacial  lakes,  the  one  most  invari- 
ably recognizable  and  most  definite  in  its  testimony  is  the  outlet  showing 

'  Proc.  A.  A.  A.  S.,  Vol.  XXXV,  for  1886,  p.  208. 


196  THE  GLACIAL  LAKE  AGASSIZ. 

distinct  stream  erosion  across  the  rim  dividing  adjacent  river  basins,  which 
now  in  many  instances  send  their  waters  respectively  to  the  Gulf  of  Mex- 
ico and  to  Hudson  Bay  or  the  Grulf  of  St.  Lawrence.  Obviously,  water- 
courses could  exist  in  these  positions  only  as  the  outlets  of  lakes  which 
were  pent  up  by  some  barrier  that  is  now  removed.  Shore-lines  traceable 
northward  from  these  deserted  channels  must  therefore  belong  to  a  lake, 
and  can  not  be  regarded  as  the  record  of  any  marine  submergence. 

Closely  associated  with  such  channels  crossing  watersheds,  and  at  the 
same  level,  are  the  three  following  classes  of  proof  cited,  namely,  eroded 
cliffs,  beach  ridges,  and  deltas ;  and  below  these  shore  records  are  the  fine 
lacustrine  sediments.  These  are  found  in  hydrographic  basins  which  are 
now  drained  by  a  continuous  descent  northward,  presenting  no  indication 
that  any  land  bai-rier  ever  existed  across  their  lower  portions  to  form  these 
lakes,  being  afterward  removed  by  erosion  or  by  depression.  The  shore- 
lines, as  shown  thus  by  wave-cut  cliffs,  wave-built  beaches,  and  deltas 
brought  by  inflowing  rivers,  extend  far  along  both  sides  of  the  present 
hydrographic  basin,  often  rising  slightly  and  regularly  northward,  instead 
of  sinking  in  that  direction,  as  they  would  do  if  there  had  been  a  depres- 
sion of  the  land  at  the  north.  When  traced  carefully  with  leveling,  they 
are  found,  sometimes  after  an  extent  of  hundreds  of  miles,  as  on  the  glacial 
Lake  Agassiz  and  about  the  great  lakes  tributary  to  the  St.  Lawrence,  to 
terminate  abruptly  where  the  basin  attains  its  greatest  width.  Hence  it  is 
manifest  that  the  barrier  of  these  lakes  could  not  have  been  land  formerly 
raised  higher  than  now,  but  was  the  receding  ice-sheet,  against  which  the 
land  shores  terminated. 

On  slopes  descending  in  parallelism  with  the  retiring  ice  border,  drain- 
age from  it  in  many  places  flowed  in  channels  from  which  the  streams 
became  turned  into  new  and  more  northerly  courses  as  the  ice  retreated. 
Several  glacial  river  coiu'ses  of  this  kind  I  have  observed  between  the 
Coteau  des  Prairies  and  the  Minnesota  River.  ^  Others  have  been  noted 
by  Gr.  M.  Dawson,^  McConnell, ^  fii^d  Tyrrell,^  in  various  parts  of  Alberta 

iGeol.  and  Nat.  Hist.  Survey  of  Miunesota,  Final  Report,  Vol.  I,  1884,  pp.  508,509,606. 
•Report  on  the  Geology  and  Resources  of  the  Region  in  the  Vicinity  of  the  Forty-ninth  Parallel, 
1875,  pp.  263-265;  Geol.  Survey  of  Canada,  Report  of  Progress,  for  1882-83-84,  p.  150  C. 

'Geol.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  I,  for  1885,  pp.  21  C  and  74  C. 
^  Ibid..  Annu;U  Report,  new  series.  Vol.  II,  for  1886,  pp.  43  E,  45  E,  and  145, 146  E. 


OUTLET  VALLEYS  HOLDING  NAEEOW  LAKES.  197 

and  Assiniboia.  But  these  seldom  were  outlets  of  glacial  lakes  of  large 
size.  It  was  only  when  extensive  hydrographic  basins  were  inclined  toward 
the  ice-sheet  that  broad  glacial  lakes,  as  those  named  Lake  Agassiz,  Lake 
Souris,  Lake  Saskatchewan,  and  the  greatly  enlarged  Laurentian  lakes 
from  Superior  to  Ontario,  were  held  between  the  northwardly  sloping  land 
and  the  waning  ice-sheet,  with  long-continued  outflow  across  the  present 
main  watersheds  of  the  continent. 

The  depth  of  erosion  of  these  outlets  varies  from  50  feet  or  less  to 
150  feet  or  more.  So  far  as  known  to  me,  they  are  cut  through  the  easily 
eroded  drift  deposits,  and  sometimes  beneath  these,  on  the  extension  of  the 
great  plains  in  the  Canadian  Northwest,  through  Cretaceous  shales  or  clays 
and  soft,  unconsolidated  sandstones,  which  could  be  easily  worn  away. 
Nowhere  is  it .  found  that  a  glacial  river  has  channeled  deeply  into  the 
harder  rock  formations.  The  time  required  for  the  work  observed  was 
brief. 

A  noteworthy  feature  of  many  of  the  old  watercourses  which  were 
outlets  of  glacial  lakes,  then  carrying  a  much  greater  volume  of  water 
than  now,  is  the  occurrence  of  long  and  narrow  lakes  in  such  valleys,  of 
which  Long  Lake,  in  Assiniboia,  lying  on  the  west  side  of  a  high  remnant 
of  the  eroded  Cretaceous  strata  called  Last  Mountain,  is  a  conspicuous 
example.  This  lake,  occupying-  one  of  the  channels  of  outflow  from  the 
glacial  Lake  Saskatchewan,  which  thence  continued  down  the  Qu'Ajjpelle 
Valley,  is  about  50  miles  long  from  south  to  north  and  1  to  2  miles  wide. 
Its  southern  end  is  separated  from  the  Qu'Appelle  River  by  alluvial  deposits 
only  a  few  feet  above  Long  Lake,  which  have  been  brought  into  the  valley 
since  its  great  glacial  river  ceased.  Similarly  the  Qu'Appelle  Valley  has 
been  partly  refilled  by  the  postglacial  deposits  of  its  tributaries,  and  the 
present  stream  in  its  course  through  the  Fishing-  Lakes  flows  at  a  level 
about  60  feet  above  the  ancient  river  bed.  Other  rivers  which  thus  flow 
through  lakes  produced  by  postglacial  alluvium  in  the  beds  of  the  outlets 
of  glacial  lakes  are  the  James  River,  formerly  the  outlet  of  Lake  Som-is ; 
the  Pembina  River,  which,  with  Langs  Valley,  aff'orded  a  later  outlet  from 
Lake  Souris,  now  marked  by  Pelican,  Rock,  and  Swan  lakes,  besides  sev- 
eral other  lakes  of  small  size ;  the  Minnesota  River,  with  Browns  Valley, 


198  THE  GLACIAL  LAKE  AGASSIZ. 

b)-  which  Lake  Ag-assiz  outflowed,  where  now  are  Lakes  Traverse,  Big 
Stone,  and  Lac  qui  Parle :  the  St.  Croix  River  and  Lake  St.  Croix,  formerly 
the  course  of  drainage  from  the  west  part  of  Lake  Superior  when  that 
lake  was  held  500  feet  higher  than  now  by  the  barrier  of  the  receding 
ice-sheet;  and  the  Illinois  River,  the  outlet  of  the  glacial  Lake  Michigan, 
flowing'  tlu'ough  Lake  Peoria. 

Eroded  cliffs. — This  type  of  shore-lines,  denominated  sea  cliff's  by  Gril- 
bert,  is  developed  where  a  glacial  lake  has  formed  a  terrace,  usually  in  the 
unmodified  glacial  drift  or  till  (see  fig.  7,  p.  26).  Waves  at  these  places 
have  been  efficient  to  erode,  by  undercutting  at  the  base  of  the  terrace; 
and  shore  currents  have  borne  away  the  eroded  material,  excepting  usiially 
a  considerable  number  of  large  bowlders.  Only  a  small  portion  of  the 
shores  of  Lake  Agassiz  examined  by  me  consists  of  these  wave-cut  slopes  of 
till;  and  they  nowhere  form  conspicuous  topographic  features,  their  range 
in  height  being  from  5  or  10  to  30  feet.  Much  higher  cliff's  of  till  of  simi- 
lar origin  exist  on  some  parts  of  the  shores  of  the  present  great  lakes  of 
the  St.  Lawrence  and  Nelson  rivers,  where  erosion  has  been  in  progress 
ever  sincB  the  time  of  the  glacial  recession.  Scarboro  Heights,  on  Lake 
Ontario,  near  Toronto,  extending  9  miles,  with  a  height  of  170  to  290  feet, 
consisting  of  till  and  interglacial  beds,  are  cliff's  thus  produced  by  post- 
glacial lake  erosion.  The  duration  of  the  glacial  lakes  apjjears  to  have 
been  much  shoi'ter  than  the  postglacial  epoch. 

It  is  important,  however,  to  note  here  that  cliff's  of  preglacial  erosion, 
which  remained  as  prominent  escarpments  through  the  vicissitudes  of  the 
Ice  age,  became  in  some  places  the  shores  of  glacial  lakes.  Of  this  class 
are  the  bold  highlands  of  Pembina,  Riding,  and  Duck  mountains,  which 
rise  steeply  100  to  1,000  feet  from  the  highest  western  shore-line  of  Lake 
Agassiz  to  form  the  margin  of  a  plateau  that  stretches  with  a  moderately 
undulatins:  surface  westwai-d.  Even  where  this  lake  washed  the  bases  of 
the  cliffs,  it  doubtless  eroded  them  only  to  a  slight  extent.  The  horizontal 
Cretaceous  beds  of  this  great  escarpment  originally  extended  eastward  a 
considerable  distance,  as  believed  by  Hind  and  Dawson,  probably  so  far  as 
to  cover  the  areas  now  occupied  by  Lake  Wimiipeg  and  the  Lake  of  the 
Woods;  and  we  must  attribute  the  ei'osion  of  their  eastern  portion,  leaving 


BEACH  RIDGES.  199 

this  steep  line  of  highlands,  to  river  action  during  the  time  of  epeirogenic 
elevation  which  closed  the  Tertiary  and  introduced  the  Quaternary  era,  not 
in  any  important  degree  to  glaciation,  and  least  of  all  to  shore-cutting  by 
the  glacial  lake. 

Beaches. — The  course  of  the  shore  of  a  large  glacial  lake  is  usually 
marked  by  a  smoothly  rounded  beach  ridge  of  gravel  and  sand  (see  PI. 
VI  and  fig.  6,  p.  26)  wherever  the  land  is  a  slope  of  till  sinking  slowly 
beneath  the  ancient  water-level.  Like  the  shore  accumulations  of  present 
lakes  and  of  the  seacoast,  the  glacial  lake  beaches  vary  considerably  in 
size,  having  in  any  distance  of  5  miles  some  portions  5  or  10  feet  higher 
than  others,  due  to  the  unequal  power  of  waves  and  currents  at  these  parts 
of  the  shore.  Moderate  slopes  bordering  the  greater  glacial  lakes  were 
favorable  for  the  formation  of  beach  ridges,  and  such  ground  frequently 
displays  many  beaches  at  successive  levels  which  marked  pauses  in  the 
gi'adual  elevation  of  the  land  when  it  was  relieved  of  its  ice  burden,  and  in 
the  subsidence  of  the  lake  as  its  outlet  became  eroded  deeper  or  as  the 
glacial  retreat  uncovered  new  and  lower  avenues  of  discharge. 

Waves  driven  toward  the  shore  by  storms  gathered  the  beach  gravel 
and  sand  from  the  deposit  of  till  or  other  drift  which  was  the  lake  bed, 
and  corresponding  deposits  of  stratified  clay,  derived  fi-om  the  same  erosion 
of  the  till,  sank  in  the  deeper  part  of  the  lake.  But  these  sediments  were 
evidently  of  small  amount  and  are  not  commonly  noticeable  on  the  sheet 
of  till  which  forms  the  greater  part  of  the  lacustrine  areas.  Where  the 
beaches  cross  delta  deposits,  especially  the  fine  silt  and  clay  that  lie  in 
front  of  the  delta  gravel  and  sand,  they  are  indistinctly  developed  or  fail 
entirely.  On  the  other  hand,  the  most  massive  and  typical  beach  ridges, 
often  continuous  several  miles  with  remarkable  uniformity  of  size,  having 
a  central  thickness  of  10  to  15  feet  and  a  total  width  of  20  to  30  rods,  are 
found  on  areas  of  till  that  rise  with  a  gentle  slope  of  10  or  15  feet  per 
mile.  Under  the  influence  of  irregular  contours  of  the  shore,  however,  the 
beach  deposits  assume  the  form  of  bars,  spits,  hooks,  loops,  and  terraces, 
of  which  Grilbert  has  given  a  careful  classification,  with  analysis  of  the 
interactions  of  waves  and  currents  by  which  they  were  made.\ 

'  "The  topographic  features  of  lake  shores:"  Fifth  Annual  Report  of  the  U.  S.  Geol.  Survey, 
1885,  pp.  75-123;  "Lake  Bonneville:"  Monographs  of  the  U.S.  Geol.  Survey,  Vol.  1, 1890,  Chapter  II. 


200  THE  GLACIAL  LAKE  AGASSIZ. 

Deltas. — A  broad  expanse  of  water  exposed  along  a  distance  of  many 
miles  to  strong  winds  is  required  for  the  formation  of  sufficiently  large  and 
powerful  waves  to  erode  cliffs  or  accumulate  well-defined  beach  ridges;  but 
the  area  of  any  glacial  lake,  small  or  large,  may  be  partly  occupied  by 
deltas  brought  into  its  margin  by  tributary  streams.  These  deposits  at  the 
mouths  of  small  brooks  are  often  only  a  few  rods  wide,  while  the  deltas  of 
rivers,  especially  those  supplied  with  much  englacial  di'ift  from  the  melting 
ice-sheet,  sometimes  extend  many  miles  in  a  flat  or  moderately  undulating- 
plain  of  gravel  and  sand,  lying  at.  the  level  which  the  surface  of  the  lake 
held  during  the  accumulation  of  the  delta,  or  within  a  few  feet  above  or 
below  that  level.  But  at  the  mouth  of  the  river  forming  the  delta  it  was 
frequently  built  up  in  a  fan-shaped  mass  to  a  considerable  height,  the  head 
of  the  alluvial  slope  being  in  some  instances  50  feet  or  more  above  the 
lake.  The  delta  plain  is  generally  bounded  on  its  lakeward  side  by  a 
somewhat  steep  descent,  partly  due  to  the  ordinary  conditions  of  delta 
formation,  but  often  made  more  conspicuous  by  erosion  of  the  outer  por- 
tion of  its  original  area  by  waves  and  shore  cm-rents  when  the  lake  fell  to 
loAver  levels. 

Winds  in  many  places  have  channeled  and  heaped  the  surface  of  the 
more  extensive  deltas,  acting  most  efficiently  as  soon  as  they  became  un- 
covered from  the  lake  and  before  they  could  be  overspread  by  vegetation; 
and  many  of  the  resulting  sand  dunes  (see  PI.  VII,  p.  28),  which  frequently 
range  from  25  to  100  feet  in  height,  though  mainly  covered  by  grass, 
bushes,  and  trees,  are  still  undergoing  slight  changes  of  their  form  by  wind 
erosion.  All  the  dunes  on  the  areas  of  the  glacial  lakes  Agassiz,  Dakota, 
Souris,  and  Saskatchewan,  occur  on  delta  deposits;  but  the  great  tracts  of 
dunes  about  the  south  end  of  Lake  Michigan  belong  wholly  to  beach  accu- 
mulations, l)eing  sand  derived  from  erosion  of  the  eastern  and  western  shores 
of  the  lake,  whence  it  has  been  borne  southward  by  shore  cun-ents,  espe- 
cially during  northern  gales.  None  of  the  beaches  of  our  glacial  lakes  are 
large  enough  to  make  dunes  like  those  on  Lake  Michigan,  though  the  size 
and  depth  of  Lake  Agassiz,  its  great  extent  from  south  to  north,  and  the 
character  of  its  shores,  seem  equally  favorable  for  their  accumulation.     It 


LAOUSTEINE  SEDIMENTS.  201 

is  thus  again  indicated  that  tlie  time  occiipied  by  the  recession  of  the  ice- 
sheet  was  comparatively  brief. 

Lacustrine  sediments. — In  front  of  the  delta  plains  of  gravel  and  sand, 
the  finer  silt  and  clay  brought  into  the  glacial  lake  by  the  same  tributaries 
were  spread  over  the  lake  bottom,  covering  the  till  on  large  tracts  adjacent 
to  the  great  deltas.  Only  small  contributions  of  fine  sediment,  usually 
inappreciable,  as  before  stated,  on  the  greater  part  of  the  lake  basin,  were 
supplied  from  the  shore  and  sublittoral  erosion  of  till,  which  yielded  the 
gravel  and  sand  of  the  beaches;  but  some  of  these  areas  of  wave  ero- 
sion, reaching  a  quarter  of  a  mile  off  shore,  are  plentifully  strewn  with  the 
residual  bowlders. 

Because  of  their  relation  to  the  receding  ice-sheet,  the  glacial  lakes 
might  be  expected  to  receive  noticeable  deposits,  including  bowlders,  from 
floating  bergs  and  from  floes  of  the  ice  foot  which  would  be  formed  in 
winter  along  their  northern  barrier.  It  is  certain,  however,  that  no 
deposits  which  can  be  referred  to  such  origin  are  spread  generally  over 
the  lake  basins.  Bowlders  are  absent  or  exceedingly  rare  in  the  beaches, 
deltas,  and  finer  lacustrine  sediments.  In  a  few  places,  however,  I  have 
observed  bowlders  in  considerable  numbers  on  esker  ridges  of  gravel  and 
sand  (pp.  186,  188),  where  they  were  evidently  brought  and  stranded  by 
floating  ice  masses  from  the  melting  ice  border,  whose  distance  could  not 
have  exceeded  a  few  miles  at  the  farthest,  and,  indeed,  probably  was  not 
so  much  as  1  mile  while  the  bowlders  were  being  stranded. 

Where  terminal  moraines  cross  a  glacial  lake,  their  knolly  and  hilly 
contour,  as  deposited  on  land,  is  changed  to  a  smoothed,  slightly  undulat- 
ing surface,  and  their  proportion  of  bowlders  exposed  to  view  is  diminished. 
The  lake  leveled  the  till  that  would  otherwise  have  formed  knobs  and  hills, 
in  which  process  many  of  its  bowlders  were  covered. 

After  the  drainage  of  the  glacial  lakes  by  the  complete  departure  of 
the  ice-sheet,  the  lower  portions  of  their  basins,  in  depressions  and  along 
the  present  river  courses,  have  become  filled  to  a  considerable  extent  by 
fluvial  beds  of  fine  silt.  These  are  similar  in  material  with  the  lacustrine 
sediments  bordering  the  deltas,  from  which  they  are  distinguishable  by, 
their  containing  in  some  places  shells  like  those  now  living  in  the  shallow 


202  THE  GLACIAL  LAKE  AGASSIZ. 

lakes  and  streams  of  the  region,  remains  of  rushes  and  sedges  and  peaty 
deposits,  and  occasionally  branches  and  logs  of  wood,  such  as  are  floated 
down  by  streams  in  their  stages  of  flood.  In  the  valley  of  the  Red  River 
of  the  North  these  recent  fluvial  deposits  have  commonly  greater  thickness 
and  extent  than  the  underlying  silt  of  the  glacial  Lake  Agassiz,  which, 
however,  in  some  portions,  as  near  the  deltas  of  the  Sheyenne  and  the 
Assiniboine,  occupies  large  areas. 

PRINCIPAT.    GLACIAL    LAKES    OF    THE    NORTHERN    UNITED    STATES 

AND    OF    CANADA. 

Netv  England,  Quebec,  the  eastern  provinees,  the  Northeast  Territory,  and 
Labrador. — Attending  the  retreat  of  the  ice-sheet  from  New  England,  Que- 
bec, and  the  eastern  provinces,  many  glacial  lakes  of  small  size  and  short 
duration  were  formed  on  areas  declining  toward  the  north  or  northwest, 
as  in  the  valley  of  the  Contoocook  River,  in  New  Hampshire;'  on  the 
western  flanks  of  the  Green  Mountain  range,  in  Vermont,  where  Mr.  C.  L. 
Whittle  informs  me  that  delta  deposits  of  such  origin  occur  up  to  heights 
of  fully  2,000  feet;  on  head  streams  of  the  River  St.  John,  in  northern 
Maine;  and  in  southern  Quebec,  between  the  Atlantic-St.  Lawrence  water- 
shed and  the  receding  ice  front.  Fewer  and  still  smaller  glacial  lakes, 
usually  leaving  no  well-marked  records  of  their  existence,  doubtless  also 
attended  the  glacial  reti-eat  in  New  Brunswick,  Nova  Scotia,  Newfound- 
land, and  Labrador.  But  soon  the  ocean-washed  ice  border  was  melted 
back  from  the  Gulf  of  St.  Lawrence  and  along  the  broad  St.  Lawrence 
Valley  perhaps  to  Quebec,  admitting  the  sea  to  the  area  of  Lake  Cham- 
plain,  which,  with  the  Hudson  Valley,  had  been  occupied  during  the  reces- 
sion of  the  ice  by  a  long  and  narrow  glacial  lake,  extending  fi'om  near  New 
York  City  to  near  Montreal,  caused  by  the  southward  elevation  and  north- 
ward depression  of  the  land.^ 

North  of  the  St.  Lawrence  the  receding  ice  opposed  no  barrier  to 
drainage  from  large  areas  until  it  withdrew  across  the  height  of  land  divid- 
ing the  St.  Lawrence  waters  from  those  tributarv  to  James  and  Hudson 


'  Geology  of  New  Hampshire,  Vol.  Ill,  1878,  pp.  103-120. 
•Bulletin,  6.  S.  A.,  Vol.  I,  p.  566;  Vol.  Ill,  pp.  484-487. 


BASINS  OF  THE  LAURENTIAN  LAKES.  203 

bays,  when  upon  the  country  around  Lake  Mistassini  and  upon  many 
other  tracts  glacial  lakes  of  considerable  size  must  have  been  formed.  In 
the  exploration  of  that  region  traces  of  these  former  lakes,  especially  of 
their  channels  crossing  the  watershed,  should  be  carefully  looked  for,  as 
not  the  least  important  of  our  records  of  the  Ice  age. 

Basins  of  the  Laurentian  lakes  and  of  Hudson  Bay. — As  soon  as  the 
border  of  the  retreating  ice-sheet  was  withdrawn  across  the  various  parts 
of  the  watershed  south  of  the  Laurentian  lakes,  each  considerable  stream 
valley  and  embayment  between  the  height  of  land  and  the  ice  front  held  a 
glacial  lake.  Doubtless  hundreds  of  channels  may  be  traced  where  these 
lakes  outflowed.  But  the  continuing  glacial  retreat  merged  these  minor 
lakes  into  a  few  of  large  size,  overflowing  at  the  lowest  passes.  In  the 
States  adjoining  on  the  south,  and  in  portions  of  Canada  on  the  north,  the 
shores  of  these  glacial  representatives  of  the  present  Laurentian  lakes  are 
recorded  by  eroded  cliffs,  beach  ndges,  deltas,  and  lacustrine  sediments; 
but  along  other  portions  of  their  Canadian  boundaries,  where  they  were 
held  in  by  the  receding  ice  barrier  on  the  northeast  and  north,  the  land 
shows  no  shore  erosion  nor  beach  deposits. 

The  west  part  of  Lake  Superior  stood  about  500  feet  higher  than  now, 
and  outflowed  by  the  St.  Croix  River.  Lake  Michigan  outflowed  by  the 
low  divide  at  Chicago  to  the  Des  Plaines  and  Illinois  rivers.  The  glacial 
Lake  Erie  was  at  first  some  200  feet  above  the  present  level  of  this  lake, 
with  overflow  to  the  Wabash;  but  later  it  obtained  lower  outlets,  the  last 
being  by  Chicago,  after  the  glacial  lakes  Erie,  Huron,  Michigan,  and 
Superior  had  been  merged  into  one  expanse,  which  Spencer  has  named 
Lake  Warren.  Lake  O-ntario,  or  rather  its  glacial  forerunner,  named  by 
Spencer  Lake  Iroquois,  becoming  by  the  retreat  of  the  ice  separated  and 
distinct  from  the  upper  lakes,  extended  far  to  the  north  and  northeast  of 
its  present  limits  and  poured  its  waters  into  the  Hudson,  at  first  by  the 
Mohawk  and  afterward  by  the  way  of  Lake  Champlain,  while  the  continu- 
ing glacial  recession  uncovered  the  country  north  of  the  Adirondacks  and 
along  the  great  valley  where  it  now  outflows  by  the  St.  Lawrence. 

The  watershed  which  divides  the  upper  St.  Lawrence  basin  from  the 
ba.sin  of  James  Bay  is  crossed  by  many  channels  of  outflow  from  glacial 


204  THE  GLACIAL  LAKE  AGASSIZ. 

lakes  pent  up  between  that  watershed  and  the  departing  ice-sheet  on  the 
north.  Kenogami  or  Long  Lake,  north  of  Lake  Superior,  having  a  length 
of  about  54  miles  from  northeast  to  southwest  and  a  width  mostly  between 
a  half  mile  and  2  miles,  forming  the  head  of  Kenogami  River,  tributary 
to  the  Albany,  occupies  the  channel  of  outlet  from  a  glacial  lake  in  the 
Albany  basin,  passing  southward  by  Trout  Lake  and  Black  River  to  Lake 
Superior.*  The  elevation  of  Kenogami  Lake,  according  to  the  survey 
of  the  Canadian  Pacific  Railway,  is  1,032  feet  above  the  sea.  Dr.  Robert 
Bell  states  in  a  letter  that  the  summit  crossed  by  the  Height  of  Land 
portage  close  south  of  this  lake,  and  leading  from  it  to  Black  River,  is 
about  70  feet  higher,  being  therefore  approximately  1,100  feet  above  the 
sea.  This  portage  "is  about  a  half  mile  long,  and  is  over  an  accumula- 
tion of  well-rounded  bowlders,  with  gravel  and  earth  filling  the  interspaces 
in  part;  at  other  parts  the  bowlders  are  piled  on  each  other  quite  naked. 
The  valley  between  the  rocky  walls  is  about  half  a  mile  wide.  The  sur- 
face is  somewhat  level,  and  there  is  a  subordinate  valley  or  depression 
sweeping  around  on  the  west  side  between  the  bulk  of  the  accumulation  of 
bowlders  and  the  rocky  bluff"  on  that  side."  The  ancient  watercourse 
thus  described  west  of  the  portage  is  probably  only  a  few  feet  above 
Kenogami  Lake,  having  very  nearly  the  same  elevation  as  the  divide  be- 
tween the  Missinaibi  and  Michipicoten  rivers,  some  150  miles  distant  to  the 
east.  Both  these  low  points  of  the  watershed  were  doubtless  occupied  by 
rivers  outflowing  from  glacial  lakes  on  the  north  during  the  recession  of 
the  ice-sheet. 

Missinaibi  Lake,  near  the  head  of  Missinaibi  River,  the  western  branch 
of  the  Moose  River  system,  is  about  1,020  feet  above  the  sea.  This  lake 
"bears  south  48°  west,  is  24  miles  long,  nearly  straight,  and  varies  from 
a  half  mile  to  IJ  miles  in  width."-  Close  southwest  of  Missinaibi  Lake,  in 
the  continuation  of  this  glacial  river  course,  is  Crooked  Lake,  at  an  eleva- 
tion of  about  1,038  feet.  "It  is  8 J  miles  long,  and  averages  less  than  a 
quarter  of  a  mile  in  width."  Near  the  head  of  Crooked  Lake,  and  only 
a  few  feet  above  it,  is  the  Height  of  Land  portage,  approximately  1,042 

1  Geol.  Survey  of  Canada,  Report  of  Progress,  1871-72,  p.  336. 

2  Ibid.,  Report  of  Progress,  1875-76,  p.  330. 


saskatchewa:si  and  eed  eiver  basins.  205 

feet  above  the  sea,  and  thence  descending  toward  Lake  Superior  the  old 
channel  contains  Dog  Lake,  having  a  height  of  about  1,026  feet,  and  Mat- 
tagaming  or  Mattawagaming  Lake,  which,  according  to  the  Canadian 
Pacific  Railway  survey,  is  1,025  feet  above  sea-level. 

When  the  Kenogami,  Missinaibi,  and  other  glacial  lakes  of  the  James 
Bay  region  became  merged  in  one  of  great  extent,  rivaling  Lake  Agassiz, 
the  outlet  of  this  confluent  lake  probably  crossed  the  low  watershed  south 
of  the  eastern  end  of  Lake  Abittibi,  passing-  to  Lac  des  Quinze  and  the 
Ottawa  River.  The  elevation  of  Lake  Abittibi,  according  to  observations 
of  the  Canadian  Geological  Survey,  is  about  857  feet  above  the  sea,  and 
the  portage  over  the  watershed  rises  only  about  100  feet  higher.  Its  pres- 
ent altitude  is  thus  nearly  a  hundred  feet  less  than  that  of  the  Kenogami 
and  Missinaibi  outlets,  and  it  is  probable  that  when  the  land  was  first 
uncovered  from  the  ice-sheet  the  Abittibi  outlet  was  relatively  lower  than 
the  others  by  a  much  greater  difference,  and  that  with  reference  to  the  sea- 
level  it  was  much  less  elevated  than  now. 

Basins  of  the  Saskatchewan  and  the  Bed  Biver  of  the  North. — Durino-  the 
recession  of  the  ice-sheet  from  Alberta  small  glacial  lakes  doubtless  existed 
in  the  basins  of  the  Bow  and  Belly  rivers,  outflowing  from  the  former  suc- 
cessively by  the  Little  Bow  River  and  the  Snake  Valley,  and  from  the 
latter  successively  by  the  Verdigris,  Etsi-kom,  and  Chin  couldes,  which 
Dr.  Dawson  describes  as  remarkable  abandoned  river  courses  now  carrying 
little  or  no  water.  The  glacial  ch-ainage  from  the  present  sources  of  the 
South  Saskatchewan,  and  probably  also  of  the  North  Saskatchewan  and 
Athabasca,  was  thus  carried  southeastward,  in  parallelism  both  with  the 
main  Rocky  Mountain  range  and  with  the  retiring  ice  border,  to  the  Milk 
River,  west  and  south  of  the  Cypress  Hills.  Thd  whole  area  of  Alberta, 
partly  land  sloping  northeastward  and  partly  ice  sloping  southwestward, 
with  glacial  lakes  here  and  there  along  the  ice  margin,  seems  then  to  have 
been  tributary  to  the  Missouri  and  the  Grulf  of  Mexico.^ 

From  Lake  Pakowki,  through  which  this  glacial  drainage  for  a  long 
time  flowed  southward  to  the  Milk  River,  the  ice  front  must  have  been 

'  6.  M.  Dawson,  Report  on  the  Geology  and  Resources  of  the  Region  in  the  vicinity  of  the  Forty- 
ninth  Parallel,  1875;  Geol.  Survey  of  Canada,  Rejiort  of  Progress  ibr  1882-83-84,  Part  C.  Compare 
with  Mr.  J,  B.  Tyrrell's  paper  in  Bulletin  G.  .S.  A.,  Vol.  I,  pp.  401,  403. 


206  THE  GLACIAL  LAKE  AGASSIZ. 

withdrawn  more  than  200  miles  to  the  east,  past  the  Cypress  Hills  and 
Wood  Mountain,  before  a  lower  outlet  from  the  Saskatchewan  country 
north  of  these  highlands  would  be  obtained  by  Twelve  Mile  Lake  and 
over  the  present  continental  watershed  to  Big  Muddy  Creek,  which  flows 
through  the  northeastern  corner  of  Montana  to  the  Missouri.  But  only  a 
slight  further  retreat  of  the  ice  was  sufficient  to  give  still  lower  avenues  of 
drainage.  As  soon  as  the  Missouri  Coteau  was  uncovei'ed  a  glacial  lake 
occupying  the  valley  of  the  South  Saskatchewan,  in  the  vicinity  of  its 
elbow,  outflowed  by  the  way  of  Moose  Jaw  Creek,  and  tlu-ough  a  glacial 
lake  in  the  upper  Souris  or  Mouse  River  basin,  to  the  Missouri  near  Fort 
Stevenson.  Later  the  outflow  from  the  Lake  Saskatchewan  may  have 
passed  to  the  Lake  Souris  by  way  of  the  Wascana  River,  after  flowing 
through  a  glacial  lake  which  probably  extended  from  Regina  60  miles  to 
the  westward  in  the  upper  Qu'Appelle  basin. 

Through  the  whole  pei'iod  of  the  existence  of  the  Lake  Souris,  which 
at  first  outflowed  to  the  Missouri  and  afterward  to  Lake  Agassiz,  the  glacial 
lake  in  the  basin  of  the  South  Saskatchewan,  doubtless  also  at  last  includ- 
ing the  North  Saskatchewan,  was  tributary  to  it,  and  the  outlet  of  this 
Lake  Saskatchewan  was  transferred  to  lower  courses  as  the  border  of  the 
ice-sheet  receded  from  southwest  to  northeast.  In  the  concluding  part  of 
this  chapter  detailed  descriptions  of  these  glacial  lakes,  and  of  their  succes- 
sive channels  of  outflow  to  Lake  Agassiz,  will  be  presented. 

Lake  Agassiz,  the  largest  of  all  the  glacial  lakes  of  North  America, 
occupying  the  basin  of  the  Red  River  of  the  North  and  Lake  Winu'peg, 
covered  extensive  tracts  of  Minnesota  and  North  Dakota,  the  greater  part 
of  Manitoba,  and  a  considerable  area  of  eastern  Saskatchewan  and  south- 
western Keewatin.  The  history  of  this  lake,  which  increased  in  area  as 
the  ice-sheet  decreased,  forms  the  central  theme  of  this  chapter,  succeeded 
by  reviews  of  the  associated  glacial  lakes  of  large  size,  two  of  which,  lying 
in  southern  Minnesota  and  in  South  Dakota,  had  their  brief  existence  before 
Lake  Agassiz,  the  others  being  contemporaneous  with  this  lake  and  several 
of  them  tributary  to  it. 

British  Columbia,  Athabasca,  and  the  Northwest  Territory. — Light-colored 
silt  deposits,  distinctly  stratified  and  of  considerable  thickness,  which  seem 


BRITISH  COLUMBIA  AND  LAKE  YUKON.  207 

to  me  referable  in  some  districts  to  glacial  lakes  and  in  others  to  river 
floods  supplied  from  the  melting  ice-sheet,  are  reported  by  Dr.  G.  M. 
Dawson  in  many  basins  of  the  British  Cordilleran  region.  His  interpre- 
tation of  their  origin,  however,  is  by  a  marine  submergence  since  the 
latest  glaciation  of  the  region.  No  fossils,  either  of  the  sea  or  of  fresh 
water,  are  found,  though  they  are  abundant  in  postglacial  marine  beds  of 
the  St.  Lawrence  Valley,  on  the  southwestern  side  of  Hudson  Bay,  and  in 
Greenland  and  Grrinnell  Land ;  but  lakes  of  only  moderate  size  tempora- 
rily bordering  the  ice-sheet  during  its  departvire  would  probably  be  desti- 
tute of  life,  and  this  would  certainly  be  true  of  rivers  produced  by  the 
glacial  melting.  These  deposits  occur,  up  to  heights  2,300  to  2,700  feet 
above  the  sea,  in  the  basin  of  the  Kootanie  and  upper  Columbia,  on  the 
interior  plateau  of  British  Columbia,  on  the  northward  extension  of  the 
great  plains  crossed  by  the  Peace  River,  and  in  the  upper  valleys  of 
the  Stikine,  Liard,  and  Yukon  rivers.^ 

On  the  last-named  river  and  the  Lewes,  tributary  to  it,  Russell  refers 
the  formation  of  silt  beds,  fully  200  feet  thick,  and  of  higher  terraces,  to  a 
glacial  lake,  named  by  him  Lake  Yukon,  150  miles  long  from  north  to 
south,  with  a  maximum  width  of  about  10  miles  and  depth  of  between 
500  and  600  feet ;  and  he  suggests  that  this  lake  was  probably  caused  by 
a  depression  of  the  upper  part  of  the  Yukon  basin  by  the  weight  of  the 
ice-sheet.  The  mouth  of  Lake  Yukon,  at  its  northern  end,  was  near 
the  northwestern  boundary  of  the  ice-sheet  at  its  maximum  extension,  the 
whole  lake  being  within  the  area  that  was  ice-covered,  as  is  known  by 
the  limits  of  glacial  drift  and  striae,  which  a-  e  first  found  in  ascending  the 
Yukon  near  the  Rink  Rapids,  approximately  in  latitude  62°  20'  north  and 
longitude  136°  15'  west,  about  160  miles  east  of  the  line  between  British 
America  and  Alaska. " 

No  other  portion  of  the  glaciated  area  of  this  continent  presents  a 
more  interesting  or  more  difficult  problem  in  Pleistocene  geology  than 
these  "white  silts,"  as  they  are  denominated  b}'  Dawson;  and  much  fur- 
ther field  work  and  study  will  be  needed  to  demonsti'ate  the  conditions  of 

'Reports  of  the  Geol.  and  Nat.  Hist.  Survey  of  Canada;  Trans.  Eoyal  Society  of  Canada,  Vol. 
VIII,  sec.  4,  1890,  pp.  3-74,  with  five  maps;  Am.  Geologist,  Vol.  VI,  Sept.,  1890,  pp.  153-162;  Nature, 
Vol.  XLII,  Oct.  30,  1890,  pp.  650-653. 

-Bulletin  G.  S.  A.,  Vol.  I,  pp.  140, 146-148,544. 


208  THE  GLACIAL  LAKE  AGASglZ. 

tlieii-  deposition  in  each  of  the  numerous  basins  in  which  they  are  found. 
But  I  believe  that  uhimately  they  will  be  shown  to  be  everywhere  attribu- 
table either  to  fluvial  deposition  attendant  on  the  recession  of  the  ice-sheet 
or  to  deposition  as  deltas  in  glacial  lakes  which  owed  their  existence  to 
ice  dams  or  to  depressions  where  the  land  had  sunk  beneath  the  ice  weight 
and  has  since  been  reelevated.  For  example,  the  Kootanie  basin  may 
well  have  been  filled  by  a  glacial  lake  obstructed  in  the  present  course  of 
drainage  by  the  retreating  ice-sheet  and  outflowing  by  the  way  of  Pack 
River  and  Lake  Pend  d'Oreille,  which  Professor  Chamberlin  finds  to  have 
been  covered  by  the  maximum  advance  of  the  ice,  while  gravel-bearing 
floods  from  the  glacial  melting  poured  thence  to  the  south  and  west.^ 
Ao-ain,  the  silts  on  the  Peace  River  east  of  the  Rocky  Mountains  seem 
referable,  as  will  be  stated  more  fully  on  a  later  page,  to  a  glacial  lake 
held  by  the  ba'n-ier  of  the  departing  ice-sheet  on  the  noi-th  and  northeast, 
with  outflow  southeastward  into  Lake  Agassiz. 

EXTBNSIOl^    OF    LAKE    AGASSIZ    WITH    THE    DEPARTURE    OF   THE 

ICE-SHEET. 

On  the  west  side  of  Lake  Agassiz  the  Dakota  lobe  of  the  ice-sheet, 
from  its  junction  with  the  Minnesota  lobe  near  the  Head  of  the  Coteau 
des  Prairies,  25  miles  west  of  Lake  Traverse  and  Browns  Valley,  at  the 
beo-innina-  of  the  moraine-forming  or  Wisconsin  di^asion  of  the  Glacial 
period,  reached  about  200  miles  south  along  the  valley  of  the  James  or 
Dakota  River  to  Yankton  and  the  Missouri ;  but  it  was  gradually  dimin- 
ished in  its  extent  until,  at  the  time  of  formation  of  the  Kiester,  Elysian, 
Waconia,  and  Dovre  moraines,  it  no  longer  retained  its  lobate  outline. 
While  these  moraines  were  being  formed  in  Minnesota  the  southwestern 
boundary  of  the  ice-sheet  in  South  and  North  Dakota  passed  from  the 
vicinity  of  Big  Stone  Lake  and  Lake  Traverse  northwesterly  along 
morainic  belts  which  have  been  traced  thi-ough  Sargent,  Ransom,  Barnes, 
and  Grio-ors  counties,  N.  Dak.,  and  bv  the  som-ces  of  the  James  and 
Sheyenne  rivers.  During  the  later  stages,  represented  by  the  Fergus  Falls 
and  Leaf  Hills  moraines,  the  Dakota  ice  front  appears  to  have  become 

'  U.  S.  Geol.  Survey,  Bulletin  No.  40,  p.  8. 


EXTENSION  FOLLOWING  THE  GLACIAL  RETREAT.  209 

again  lobate,  extending  from  the  west  shore  of  Lake  Agassiz  southward 
and  then  westward  and  northward,  between  the  lake  area  and  the  Sheyenne 
River,  to  the  prominent  and  typical  moraines  that  are  found  south  of 
Stump  and  Devils  lakes,  on  the  Big  Butte,  about  Broken  Bone  Lake  and 
northward,  and  on  Turtle  Mountain.  In  their  remarkable  development 
these  moraines  are  similar  to  the  massive  Leaf  Hills,  with  which  they  seem 
to  have  been  contemporaneous.  The  laving  action  of  Lake  Agassiz  caused 
the  thick  portion  of  the  ice-sheet  filling  the  Red  River  Valley  to  melt  back 
somewhat  faster  than  its  thinner  portions  on  the  higher  land  areas  at  each 
side. 

The  highest  of  the  Herman  beaches  of  Lake  Agassiz  extends  in  Min- 
nesota, as  traced  in  this  survey,  to  the  north  side  of  Maple  Lake,  20  miles 
east-southeast  of  Crookston,  and  probably  it  continues  thence  into  the  for- 
est region  on  the  east,  where  it  is  impracticable  to  follow  its  course,  to  the 
vicinity  of  Red  Lake;  and  on  the  west  it  reaches  through  North  Dakota 
and  at  least  14  miles  into  Manitoba,  terminating  on  the  northern  part  of  the 
Pembina  escarpment  somewhere  between  Thornhill  and  its  northern  end, 
that  is,  between  14  and  40  miles  north  of  the  international  boundary.  Be- 
fore the  formation  of  this  beach  was  completed  the  ice-sheet  had  retired 
from  the  lake  ai'ea  as  far  north  as  the  beach  extends.  During  pauses  of 
this  glacial  recession  the  Dovre,  Fergus  Falls,  Leaf  Hills,  and  Itasca  mo- 
raines were  formed,  showing  a  northward  retreat  of  the  ice  border  from  the 
Dovre  moraine  across  a  distance  of  about  150  miles  in  central  Minnesota 
and  150  to  200  miles  in  North  Dakota  and  southern  Manitoba,  with  a  max- 
imum of  probably  not  less  than  300  miles  in  the  Red  River  Valley,  where 
Lake  Agassiz  produced  a  more  rapid  melting  of  the  ice  margin.  Through 
this  time  the  River  Warren,  outflowing  from  this  glacial  lake,  fed  by  abun- 
dant ice-melting  and  rains,  eroded  a  channel  about  50  feet  deep,  approxi- 
mately from  1,100  to  1,050  feet  above  the  sea,  or  perhaps  it  eroded  only 
the  lower  half  of  that  depth,  in  the  moderately  undulating  sheet  of  till 
which  reached  across  the  present  valley  of  Lakes  Traverse  and  Big  Stone. 
The  shortness  of  the  time  thus  indicated  as  probably  occupied  in  the  for- 
mation of  a  single  one  of  the  beaches  of  Lake  Agassiz,  reafiirmed  as  it  is 
by  the  small  amount  of  the  littoral  erosion  and  resulting  beach  deposits, 
MON  xxv 14 


210  THE  GLACIAL  LAKE  AGASSIZ. 

may  well  astonish  us  iu  what  it  implies  concerning  the  rapidity  of  the  re- 
cession of  the  ice-sheet,  and  the  brevity,  geologically  speaking,  of  the  stages 
of  pause  or  readvance  when  its  moraines  were  accumulated. 

Between  the  times  of  accumulation  of  the  successive  terminal  moraines, 
the  ablation  of  the  ice  surface  and  the  retreat  of  its  border  caused  the  por- 
tion of  the  drift  which  had  been  inclosed  within  the  ice-sheet  to  be  rapidly 
deposited  on  the  land,  partly  as  till  and  partly  as  stratified  gravel,  sand,  and 
clay,  brought  by  the  streams  that  were  produced  by  the  glacial  melting. 
Thus  while  the  series  of  Herman  beaches  was  being  formed  not  only  were 
several  large  moraines  amassed,  but  also  much  englacial  till  was  spread 
over  the  country  between  the  moraines,  and  glacial  rivers  deposited  a  broad 
belt  of  modified  drift  that  stretches  from  central  Minnesota  to  Red  Lake 
and  the  Lake  of  the  Woods,  and  continues  northward  in  Manitoba,  as  de- 
scribed in  pages  181-183.  The  most  southeastern  part  of  this  prolonged 
tract  of  plentiful  modified  drift,  in  the  vicinity  of  St.  Paul  and  Minneapolis 
and  northwestward  to  St.  Cloud,  belongs  to  a  time  previous  to  Lake  Agas- 
siz;  the  portion  of  these  stratified  beds  between  St.  Cloud  and  Lake  Itasca 
represents  the  time  of  formation  of  the  highest  Herman  beach;  and  the 
deposition  of  their  u(irthern  half,  continuing  from  the  headwaters  of  the 
Mississippi  to  the  southwest  part  of  the  Lake  of  the  Woods  and  to  the  Birds 
Hill  group  of  eskers,  was  contemporaneous  with  the  lower  Herman  shores 
of  Lake  Agassiz.  Toward  this  belt  great  areas  of  the  ice-slieet  sloped  con- 
vergingly  during-  its  maximum  extension,  and  in  the  early  part  of  its  time  of 
recession  rivers  flowed  thither  from  the  ice-lobes  on  the  northeast  and  north- 
west until  this  glacial  lake  began  to  exist  and  to  grow  northward,  occupying 
the  Red  River  Valley. 

STAGES    OF    GROWTH    SHOWN    BY    MORAINES. 

The  retreat  of  the  ice  between  the  Waconia  and  Dovre  moraines  (pp. 
142,  147)  began  to  uncover  the  southern  end  of  the  bed  of  Lake  Agas- 
siz, into  which  the  inflowing  glacial  Sheyenne  River,  even  at  that  early 
stage,  brought  much  gravel  and  sand.  Tliis  first  delta  deposit  of  the  glacial 
lake  is  spread  along  its  southwestern  margin  from  near  Taylor  Lake  to  the 
bluff,  in  the  northeast  coi'ner  of  South  Dakota,  that  overlooks  the  valley  of 


STAGES  OF  GROWTH  SHOWN  BY  MORAINES.  211 

Lake  Traverse  and  tlie  Bnis  des  Sioux  River,  about  4  miles  southwest  of 
White  Rock,  lying  100  feet  below  this  gravel  and  sand  bluff.  The  same 
high  tract  was  at  that  time  continuous  also  southeastward  across  the  present 
valley,  which  is  4  miles  wide,  to  the  plateau  in  Traverse  County,  Minn., 
between  the  Bois  des  Sioux  and  Mustinka  rivers,  which  is  crossed  and  cut 
into  by  the  railway  in  section  26,  township  128,  range  47.  A  thickness 
of  12  feet  of  this  delta  of  gravel  and  sand,  having  a  surface  75  feet  above 
Lake  Traverse,  is  shown  by  the  railway  excavation,  without  exposing  its 
plane  of  contact  with  the  underlying  till,  which  forms  the  basal  part  of  the 
plateau  and  extended,  before  its  erosion  by  the  outflow  from  Lake  Agassiz, 
in  an  inclined  plane  gradually  rising  to  the  bluff  of  till,  100  to  110  feet  high, 
east  of  the  northern  end  of  Lake  Traverse.  In  this  incipient  stage,  con- 
temporaneous with  the  accumulation  of  the  Dovre  moraine.  Lake  Agassiz 
stretched  nearly  30  miles  from  northwest  to  southeast,  with  a  width  varying 
from  1  to  2  or  3  miles,  being  probably  widest  in  the  vicinity  of  Wheaton, 
Minn.,  at  its  southern  end,  where  the  River  Warren  flowed  away  south- 
westward.  The  lake  in  this  stage  was  little  more  than  a  broad  expansion 
of  the  glacial  representative  of  the  Sheyenne  River,  which  deposited  its 
delta  sediments  along  the  edge  of  the  lacustrine  area,  being  walled  in  by 
the  front  of  the  ice-sheet. 

With  the  glacial  recession  thence  to  the  Fergus  Falls  moraine  (p.  158) 
Lake  Agassiz  attained  a  length  of  about  120  miles  from  Lake  Traverse 
north  to  Ada,  Caledonia,  and  Hillsboro,  with  a  width  of  40  to'  50  miles, 
occupying  thus  an  area  of  about  5,000  square  miles  (PI.  XIX).  Its  depth 
at  Breckenridge  and  Wahpeton  was  approximately  100  feet;  at  Moorhead 
and  Fargo,  200  feet;  and  at  Caledonia,  275  feet. 

In  the  earliest  part  of  this  extension  of  the  lake  its  outlet  by  the  River 
Warren  seems  to  have  been  for  a  short  time  about  25  feet  higher  than  dur- 
ing the  later  and  much  longer  part  of  this  stage  of  recession  of  the  ice  and 
growth  of  the  lake,  as  is  shown  by  the  Milnor  beach,  a  less  distinct  shore 
deposit  than  the  Herman  beach  and  20  to  25  feet  above  it,  which  was 
observed  near  Milnor,  N.  Dak.,  and  along  a  distance  of  about  10  miles  thence 
northwest  to  the  Sheyenne,  but  was  not  recognized  farther  north  nor  in 
Minnesota.     The  Sheyenne  at  the  time  of  formation  of  the  Milnor  beach 


212  THE  GLACIAL  LAKE  AGASSIZ. 

had  become  established  in  the  course  which  it  now  has  to  its  debouchure 
into  Lake  Agassiz  at  the  present  most  southern  bend  of  the  river.  Its  large 
delta  there  brought  into  the  lake  was  already  in  progress  of  deposition  dur- 
ing the  accumulation  of  the  Milnor  beach-ridges  and  partly  supplied  the 
gravel  and  sand  of  which  they  are  formed. 

But  the  River  Warren  quickly  cut  down  its  channel  to  the  base  of 
the  earlier  Sheyenne  deposit  of  gravel  and  sand  before  described,  lying 
above  the  present  valley  of  the  Bois  des  Sioux,  until  it  reached  the  harder 
till,  and  there  was  stayed  during  the  numerous  stages  of  lacustrine  extension 
and  glacial  retreat  which  are  represented  by  the  single  Hei'man  beach  of 
this  southern  portion  of  the  lake.  The  growth  of  the  great  Sheyenne  delta 
continued,  aud  the  Buffalo  delta  was  probably  mostly  completed,  during 
the  withdrawal  of  the  ice-sheet  to  the  Fergus  Falls  moraine  and  its  pause 
or  readvance  by  which  that  moraine  was  made.  Through  the  same  stage, 
excepting  its  very  short  early  portion,  represented  by  the  Milnor  beach,  and 
for  a  long  time  afterward.  Lake  Agassiz  held  its  Herman  level,  changing 
only  very  slightly  in  this  southern  area  by  slow  erosion  of  the  outlet,  but 
experiencing  northward  a  gradual  uplifting  of  its  basin,  whereby  its  Her- 
man beach,  single  at  the  south,  becomes  double  and  multiple  in  proceeding 
to  the  north. 

The  next  stage  in  the  departure  of  the  ice  withdrew  portions  of  its 
border  to  the  ninth  or  Leaf  Hills  moraine  (p.  163),  which  is  closely  associ- 
ated with  the  Fergus  Falls  moraine,  the  two  being  merged  together  through 
much  of  their  course.  Lake  Agassiz,  therefore,  gained  only  a  small  exten- 
sion of  its  length  and  area  (PI.  XIX).  The  most  notable  change  was  the 
formation  of  a  nortliwestern  bay  of  the  lake,  I'eaching  in  a  reentrant  angle 
of  the  ice-sheet  to  Larimore  and  McCanna,  which  received  the  Elk  Valley 
delta,  deposited  by  a  large  glacial  river  flowing  from  the  depression  on 
the  ice  surface  where  the  descending  slopes  of  its  Minnesota  and  Dakota 
lobes  met. 

After  these  contiguous  and  partly  combined  moraines  were  formed, 
the  increasing  wai'mth  of  the  climate  again  pushed  back  the  ice  border 
a  long  distance,  until  its  retreat  was  temporarily  interrupted  at  the  line 
marked  by  the  tenth  or  Itasca  moraine  (p.  173).     Advancing  northward, 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.  XIX. 


JULIUS  BIEN  8  CO  ^ 


MAP  SHOWINGTIffi  E)a'ENT  OF  UKE  AGASSIZ  AT  THE  T&KS  Oin'^ORMAT10NH)F  T^^^ 

Scale, about  42  luiLea  to  aiiiitch. 
Area  of  Lake  A^assizconteinpoVaiieoiis  vitli  the  Fergus  Falls  Moraine   I I         Area  added  al  tlie  time  ot  the  Leaf  Mills  Moraine  L 

FergiLs Falls  (eiglitlL)  and  Leaf  Uills  (ninth)  Moraines  H^l 


STAGES  OF  GROWTH  SHOWN  BY  MORAINES.  213 

Lake  Agassiz  then  expanded  beyond  the  limit  of  the  international  boun- 
dary, reaching  probably  to  Winnipeg  and  Birds  Hill  (PL  XX).  The 
entire  area  of  this  lake  in  North  Dakota  had  become  uncovered  from  the 
ice,  a  lobe  of  which,  however,  remaining  on  the  Pembina  Mountain  pla- 
teau, closely  bordered  the  shore  along  a  distance  of  50  miles  south  from 
the  Manitoba  line.  In  northwestern  Minnesota  the  lake  washed  the  base 
of  ice  cliffs  that  formed  its  eastern  shore,  beginning  about  40  miles  north 
of  Lake  Itasca  and  running  north-northwesterly,  as  I  have  supposed,  to  an 
angle  of  the  ice  front  at  Birds  Hill,  from  which  a  similar  long,  high  coast  of 
ice  appears  to  have  stretched  southwestward  to  the  Pembina  Mountain  in 
the  vicinity  of  Thornhill,  being  the  northwestern  barrier  of  the  widening 
and  deepening  lake.  The  water  surface  was  about  290  miles  in  length, 
110  miles  in  maximum  width,  and  approximately  16,000  square  miles  in 
area;  and  the  depth  of  water  above  St.  Vincent,  Pembina,  and  Emerson 
was  about  450  feet,  while  its  maximum  above  the  site  of  the  city  of  Win- 
nipeg was  not  less  than  550  feet.  The  extent  of  the  portion  of  the  lake  in 
Manitoba  at  this  time  was  probably  about  3,600  square  miles. 

Once  more  the  margin  of  the  ice-sheet  recedes,  and  next  halts  at  the 
eleventh  or  Mesabi  moraine  (p.  177),  having  relinquished  the  whole  of  its 
area  in  North  Dakota,  but  still  lingering  on  a  large  tract  of  northern  Min- 
nesota, from  Red  Lake  and  Lake  Winnebagoshish  eastward  to  Lake  Supe- 
rior near  the  international  boundary.  The  great  glacial  lake  has  now 
extended  north  to  the  south  end  of  Lakes  Winnipeg  and  Manitoba,  attain- 
ing a  length  of  about  325  miles,  a  maximum  width  of  130  miles  from  the 
east  end  of  the  south  half  of  Red  Lake  to  Larimore,  and  an  area  not  far 
from  26,000  square  miles,  of  which  fully  one-third  was  comprised  in  Mani- 
toba (PI.  XX).  Its  maximum  depth,  lying  over  the  present  mouth  of  the 
Red  River,  was  about  650  feet,  and  its  depth  above  the  south  end  of  Lake 
Manitoba  was  525  feet,  very  nearly. 

These  estimates  of  depths,  it  is  to  be  noted,  are  derived  from  the 
determinations  of  the  height  of  the  shore-lines  formed  during  the  highest 
Herman  stage,  with  allowance  for  the  known  north-northeastward  differ- 
ential elevation  of  the  basin  since  the  old  plane  of  the  lake  sm-face  was 
marked  by  the  waves  of  storms.     This  earliest  and  highest  level  of  Lake 


214  THE  GLACIAL  LAKE  AGASSIZ. 

Agassiz  (excepting  ouly  the  uuimportant  stage  recorded  by  the  Milnor 
beach)  extended  north  along  the  Pembina  Mountain  into  Manitoba  and 
northeast  to  the  south  side  of  Red  Lake,  being  contemporaneous  with  the 
accumulation  of  the  Fergus  Falls,  Leaf  Hills,  Itasca,  and  Mesabi  moraines, 
so  that  the  single  lacustrine  plane  of  the  uppermost  in  the  series  of  the 
Herman  beaches  covered,  at  its  final  stage  of  greatest  extent,  all  of  the 
lake  area  to  the  latest  of  these  moraines,  which  is  the  most  northern  one 
that  has  been  definitely  traced  and  mapped  across  this  area. 

Yet  again,  and  doubtless  many  times  again,  the  ice-sheet  was  com- 
pelled to  retreat  across  spaces  of  varying  widths,  sturdily  resisting  the 
encroachments  of  the  warmer  climate  and  of  its  product,  the  glacially 
dammed  lake,  pausing  here  and  there  long  enough  to  heap  up  moraines, 
then  shrinking  and  dissolving  away  from  new  tracts  strewn  with  its  drift 
deposits.  When  future  researches  shall  enroll  the  numbers  and  delineate 
the  courses  of  the  probably  many  morainic  belts  lying  still  farther  north, 
it  will  be  250ssible  to  show  the  later  stages  of  the  gradual  extension  of  this 
lake  along  the  great  Cretaceous  escarpment  and  over  the  great  lakes  of 
Manitoba,  across  Rainy  Lake,  the  Lake  of  the  Woods,  and  the  Winnipeg 
River,  over  a  large  region  east  of  Lake  Winnipeg,  and  to  some  now 
unknown  distance  down  the  Nelson  River. 

Step  by  step,  as  fast  as  the  ice-sheet  waned.  Lake  Agassiz  grew.  The 
whole  lacustrine  area,  as  mapped  provisionally  for  its  northern  and  north- 
eastern boimdaries  on  PI.  Ill,  was  about  110,000  square  miles  or  more, 
considerably  exceeding  the  combined  areas  of  the  great  Laurentian  lakes. 
Although  it  was  not  entirely  occupied  by  Lake  Agassiz  at  any  one  stage 
of  its  existence,  the  beaches  and  terminal  moraines  indicate  that  the  lake, 
during  both  its  earlier  and  later  stages,  covered  the  greater  part,  probably 
three-fourths,  of  this  area. 

The  chief  evidence  of  such  great  extension  of  the  lake  during  the  first 
half  of  its  history  is  the  observed  extent  of  the  higher  and  earlier  Herman 
and  Norcross  beaches,  which  have  been  mapped  from  near  Red  Lake,  Min- 
nesota, southward  to  Lake  Traverse,  and  thence  northward  thi'ough  North 
Dakota  to  Riding  and  Duck  mountains  in  Manitoba,  a  distance  of  about 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XX. 


JULIUS  BIEN   a  CO   I- 


MAP  SHOWING  THE  EXTEOT  OF  I^AIffi  .AOASSIZ  AT  TliK  TIMES  OF  FORMATION  OF  THE  ITASCA  AND  MESABI  MORAINES. 

Scale,  about  42  miles  to  an  inch. 

Area  of  Lake  Agassiz  contemporaneous  with  (lie  ItascaMoraine   I I         Area  added  at  the  Ihue  of  the  Mesabi  Moraine  I I 

Itascadeiithlarul  iMesahi  (eh-'NT-nlhlMoi-iiiueh  I I 


STAGES  OF  GEOWTH  SHOWK  BY  MOKAINES.  215 

700  miles.  Delta  sand  deposits,  brought  into  Lake  Agassiz  by  the  Sas- 
katchewan and  referable  to  the  Herman,  Norcross,  and  later  stages,  reach 
from  near  Prince  Albert,  on  the  North  Saskatchewan,  about  40  miles  west 
of  the  fork  of  the  North  and  South  branches,  through  a  distance  of  more 
than  100  miles  eastward  to  the  head  of  the  Seepanock  Channel  and  the 
one  hundred  and  third  meridian.^  The  descent  of  the  river  in  this  distance 
is  approximately  from  1,275  or  1,300  feet  to  950  feet,  and  the  elevation  of 
the  west  part  of  the  delta  is  about  1,350  to  1,400  feet  above  the  sea.  As 
early  as  the  time  of  the  lower  beaches  of  the  Herman  series,  therefore,  the 
recession  of  the  ice-sheet  had  permitted  the  lake  to  extend  along  the  whole 
front  of  the  Manitoba  escarpment  to  the  latitude  of  the  north  end  of  Lake 
Winnipeg.  The  length  of  Lake  Agassiz  at  that  time  was  550  miles  or 
more,  and  I  believe  that  its  average  width  was  not  less  than  150  miles, 
reaching  east  to  the  moraine  which  Mr.  J.  B.  Tyrrell  describes  as  forming 
the  eastern  shores  and  islands  of  Lake  Winnipeg,  with  a  height  of  100  feet 
on  Black  Island.^  This  moraine  would  then  have  been  deposited  in  water 
600  to  700  feet  deep,  bordering  the  ice  margin;  its  knolly  and  irregular 
accumulations  of  drift  would  not  have  been  subjected  to  the  leveling  action 
of  the  lake  waves  until  the  further  melting  of  the  ice  opened  avenues  of 
outflow  to  Hudson  Bay  and  reduced  the  glacial  lake  nearly  to  the  level  of 
Lake  Winnipeg;  and  the  latest  change  of  the  northward  outlets  may  have 
lowered  the  water  surface  so  rapidly  and  to  such  vertical  amount  that  it 
left  no  distinct  marks  of  erosion  or  shore-lines  on  the  upper  portion  of  the 
moraine. 

Before  the  successive  northeastward  outlets  began  to  drain  Lake  Agas- 
siz below  its  channel  of  southward  discharge  at  Lakes  Traverse  and  Big 
Stone,  the  border  of  the  ice-sheet  had  been  gradually  melted  back  from 
Lake  Winnipeg  doubtless  far  toward  Hudson  Bay,  and  perhaps  even  its 
thick  central  part,  which  occupied  the  basin  of  Hudson  and  James  bays, 
had  so  far  disappeared  as  to  admit  the  sea  there.  At  a  time  of  halt  or  read- 
vance,  interrupting  this  recession,  another  terminal  moraine  appears  to  have 
been  accumulated,  crossing  the  Churchill  and  Nelson  rivers,  as  observed 

'  Canadian  Pacific  Railway  Report,  1880,  pp.  14, 19. 

2  "  Pleistocene  of  the  Winnipeg  Basin,"  Am.  Geologist,  Vol.  VIII,  pp.  19-28,  July,  1891. 


216  THE  GLACIAL  LAKE  AGASSIZ. 

by  Dr.  Robert  Bell.^  If  tliis  belonged  to  the  time  of  tlie  Campbell  or 
McCauley\alle  beaches,  as  seems  most  probable,  the  extent  of  the  lake  dur- 
mg  these  later  stages  of  southward  outflow  was  even  greater  than  I  have 
supposed  it  to  be  at  the  time  of  the  Herman  and  Norcross  beaches,  and  the 
area  occupied  by  Lake  Agassiz  in  its  numerous  stages  much  exceeded 
that  of  my  map  and  estimate. 

Measui-ed  on  the  maps  of  this  report,  the  portion  of  Lake  Agassiz 
comprised  Avithin  the  limits  of  Minnesota  has  an  area  of  apjjroximately 
16,000  square  miles,  and  its  portion  in  North  Dakota  is  6,800  square  miles, 
very  nearly,  making  together  a  tract  of  about  21,800  square  miles  in  the 
United  States,  probably  all  uncovered  from  the  ice  and  occupied  by  the  lake 
during  the  time  of  formation  of  the  Herman  series  of  beaches.  Within 
the  limits  of  Manitoba  and  adjacent  parts  of  Saskatchewan  and  Keewatin 
the  extent  attained  by  Lake  Agassiz  during  its  Herman  and  Norcross  stages 
was  probably  at  least  65,000  square  miles.  Somewhat  more  than  tlu-ee- 
quarters  of  its  expanse  then  was  north  of  the  international  boundary,  for 
while  the  lake  expanded  northward  with  the  recession  of  the  ice-sheet,  the 
southern  part  of  the  basin  was  being  uplifted  and  the  lake  was  slowly  cut- 
ting down  its  outlet,  so  that  it  had  already  relinquished  the  margins  of  its 
earliest,  area  in  Minnesota  and  North  Dakota. 

During  the  stages  of  the  lake  represented  by  the  Tintah,  Campbell, 
and  McCauleyville  beaches,  probably  its  area  occupied  by  water  at  one 
time  grew  to  exceed  100,000  square  miles.  Its  southern  portion,  however, 
was  meanwhile  diminishing,  until  at  that  late  time  of  maximum  size  of 
Lake  Agassiz  not  more  than  a  tenth  or  perhaps  a  fifteenth  part  of  its 
water  surface  was  in  the  United  States.  The  decrease  was  in  width,  not 
in  length,  for  at  its  maximum  stage  the  outflow  was  doubtless  still  to  the 
south  by  the  River  Warren. 

EEDUCTION  TO  THE  PRESENT  GREAT  LAKES  OF  MANITOBA. 

By  the  melting  away  of  the  ice-sheet  from  the  country  northeast  of 
Lake  Agassiz  this  glacial  lake  at  lengih  (obtained  successive  outlets  lower 
than  that  through  Lakes  Traverse  and  Big  Stone  and  the  Mimiesota  River. 
Owing  to  the  northeastward  depression  of  the  ice-laden  area,  the  earliest  of 

1  Bulletin,  G.  S.  A.,  Vol.  I,  pp.  303,  306. 


BEACHES  OBSBEVED  BY  ME.  TYEEELL.  217 

these  outlets  may  have  flowed  to  the  east  and  south,  passing  along  the 
margin  of  the  receding  ice  into  Lake  Superior,  and  thence  into  the  Missis- 
sippi by  the  way  of  the  Chicago  outlet  of  the  glacial  Lake  Warren,  as 
Prof.  J.  W.  Spencer  has  named  the  confluent  glacial  lake  which  is  now 
reduced  and  separated  into  parts  as  the  five  great  lakes  of  the  St.  Law- 
rence. After  the  glacial  melting  had  proceeded  so  far  as  to  open  the  great 
area  of  Hudson  and  James  bays  to  the  entrance  of  the  ocean,  Lake  Agassiz 
was  tributary  for  some  time  to  this  .inland  sea  by  outlets  higher  than  the 
Nelson  River,  while  the  ice-sheet  west  of  Hudson  Bay  was  withdrawing 
northward. 

Some  of  the  lowest  and  latest  stages  of  Lake  Agassiz  during  its  de- 
crease as  it  was  drained  away  by  its  northeastern  outlets,  each  in  succes- 
sion lower  than  the  preceding,  are  shown  by  Mr.  J.  B.  Tyrrell's  observations 
of  beaches  on  Kettle  Hill  close  south  of  Swan  Lake,  on  the  portage 
between  Lake  Winnipegosis  and  Cedar  Lake,  and  in  the  vicinity  of  the 
Grand  Rapids  of  the  Saskatchewan.^  Between  the  time  of  formation  of 
the  Stonewall  beach  and  that  of  the  Niverville  beach  the  surface  of  Lake 
Agassiz  was  lowered  45  or  50  feet,  from  a  level  slightly  higher  than  Lake 
Winnipegosis  to  one  slightly  lower  than  Lake  Manitoba.  The  former  of 
these  levels  seems  to  be  represented  near  the  .mouth  -of  the  Saskatchewan 
by  a  beach  140  feet  above  Lake  Winnipeg,  or  850  feet  above  the  sea;  and 
the  latter  becomes  apparently  double  or  triple,  being  represented  by  three 
beach  ridges,  95,  90,  and  80  feet  above  Lake  Winnipeg.  These  beaches, 
if  my  correlation  as  thus  stated  is  coiTCct,  are  nearly  horizontal  throughout 
their  observed  extent  of  nearly  300  miles  from  south  to  north,  and  show 
that  the  diff"erential  northward  uplift  of  the  basin  of  Lake  Agassiz  was 
almost  completed  before  the  ice  barrier  was  melted  back  from  the  area 
crossed  by  the  Nelson  River. 

According  to  my  correlation  of  the  five  shore-lines  nioted  by  Mr.  Tyr- 
rell on  Kettle  Hill,  successively,  in  descending  order,  1,070,  1,015,  995,  955, 
and  920  feet  above  the  sea,  the  highest  belongs  to  the  Hillsboro  stage«of 
Lake  Agassiz;  the  next  two  to  the  Emerado  stage,  there  divided  because 
of  northward  uplifting  of  the  land;  while  the  lower  two  are,  respectively, 

'  "Pleistocene  of  the  Winnipeg  Basin."  Am.  Geologist,  Vol.  A'lII.  pp.  19-28,  July.  1891. 


218  THE  GLACIAL  LAKE  AGASSIZ. 

the  second  of  the  Ojata  beaches  and  the  Gladstone  beach.  This  locaHty  is 
about  235  miles  north  of  the  international  boundary,  being  150  miles  north 
from  the  latitude  of  Gladstone,  Arden,  and  Neepawa,  the  most  northern  line 
upon  which  my  own  explorations  supply  a  comparison  of  the  beaches  and 
determination  of  their  northward  ascent. 

At  the  time  of  formation  of  the  Hillsboro  beach,  which  had  been 
already  preceded  by  the  three  higher  Blanchard  levels  of  Lake  Agassiz 
since  it  first  began  to  outflow  northeastward,  the  lake  surface  thus  appears 
to  have  been  about  140  and  240  feet,  respectively,  above  the  southern  por- 
tions of  the  present  Lakes  Manitoba  and  Winnipeg,  and  approximately  240 
and  360  feet  above  the  northern  portions  of  Lakes  Winnipegosis  and  Win- 
nipeg, the  northward  ascent  of  the  Hillsboro  beach  being  nearly  120  feet 
in  the  150  miles  between  Gladstone  and  Kettle  Hill.  Lake  Agassiz  during 
this  stage  stretched  south  in  the  Red  River  Valley  about  15  miles  beyond 
Fargo  and  Moorhead;  and  its  total  length  was  probably  not  less  than  650 
miles,  with  a  maximum  width  of  about  200  miles. 

During  the  formation  of  the  two  Emerado  beaches  the  lake  on  the 
latitude  of  Kettle  Hill  was  about  185  and  165  feet,  respectively,  above  the 
northern  part  of  Lake  Winnipegosis,  to  which  118  feet  should  be  added 
for  its  depth  above  Lake  Winnipeg,  besides  some  undetermined  amount  of 
present  northeastward  ascent  of  the  plane  of  that  lake  surface  in  the  dis- 
tance of  more  than  a  hundred  miles  to  the  north  end  of  Lake  Winnipeg. 
The  Emerado  level  of  Lake  Agassiz  began  at  the  south  about  5  miles 
north  of  Moorhead  and  Fargo,  and  stretched  probably  600  miles  to  the 
north.  Its  width  was  little  less  than  that  of  the  Hillsboro  stage;  but  the 
northward  uplifting  of  the  lower  Emerado  beach  between  Gladstone  and 
Kettle  Hill  has  been  only  85  feet. 

When  the  lake  held  its  two  Ojata  stages  and  Gladstone  stage,  the 
depth  of  water  above  Lake  Winnipegosis  was,  successively,  about  140,  125, 
and  90  feet;  and  its  extension  southward  in  the  Red  River  Valley  was  for 
the  lower  Ojata  beach  to  Caledonia,  near  the  mouth  of  the  Goose  River, 
and  for  the  Gladstone  beach  to  the  vicinity  of  Belmont,  N.  Dak.,  about  20 
miles  south  of  Grand  Forks.  The  portion  of  Lake  Agassiz  extending  into 
the  United  States  at  the  Gladstone  stage  had  a  length  of  almost  100  miles; 


BEACHES  OBSERVED  BY  MR.  TYRRELL.  219 

and  the  total  length  of  the  glacial  lake,  then  near  the  middle  of  its  entire 
tiine  of  northeastward  outflow,  was  more  than  500  miles,  with  probably 
one-third  as  great  width  in  its  northern  part.  '  The  amount  of  upward 
tilting  toward  the  north  upon  the  area  extending  150  miles  from  Gladstone 
to  Kettle  Hill  since  the  Grladstone  beach  was  formed  has  been  40  or  45 
feet.  About  twice  as  much  tilting  had  occurred  there  between  the  times 
of  formation  of  the  Hillsboro  and  Gladstone  beaches  as  since  the  date  of 
the  later  one  of  these  shore-lines.  Lake  Agassiz  in  its  Gladstone  stage 
had  become  reduced  probably  to  half  of  its  earlier  maximum  extent. 

Mossy  portage,  between  Lake  Winnipegosis  and  Cedar  Lake,  is  about 
60  miles  northeast  of  Kettle  Hill;  and  the  Grand  Rapids  of  the  Saskatche- 
wan, near  its  mouth,  are  about  25  miles  farther  east.  Both  these  localities 
are  nearly  on  latitude  53°  10'  north,  being  some  50  miles  north  of  the 
latitude  of  Kettle  Hill  and  285  miles  north  of  the  international  boundary. 
The  summit  of  the  eastern  Mossy  portage  is  described  by  Mr.  Tyrrell  as  a 
gi-avel  ridge  with  crest  93  feet  above  Lake  Winnipegosis  or  921  feet  above 
the  sea.  It  is  doubtless  a  beach  formed  by  Lake  Agassiz  when  it  stood 
here  at  the  level  of  about  910  feet.  Descending  southward  to  Lake  Win- 
nipegosis, the  portage  crosses  another  beach  ridge  with  its  crest  27  feet  and 
its  base  about  15  feet  above  this  lake,  and  it  is  therefore  clearly  referable 
to  a  level  of  Lake  Agassiz  about  845  feet  above  the  sea.  These  stages  of 
the  glacial  lake  are  quite  surely  the  same  which  made  the  Burnside  and 
Stonewall  beaches  near  the  south  end  of  Lake  Manitoba  and  the  city  of 
Winnipeg.  An  escarpment  crossed  by  the  portage  midway  between  these 
beacli  ridges  appears  to  mark  the  position  of  the  intermediate  Ossowa  shore. 

The  Burnside  lake  level  reached  south  in  the  Red  River  Valley  to 
Grand  Forks,  and  had  an  entire  length  of  nearly  500  miles  thence  to  the 
latitude  of  55°  north,  with  a  width  from  150  to  175  miles  in  its  northern 
half  Above  the  southern  end  of  Lake  Winnipeg  the  depth  of  Lake  Agassiz 
at  this  stage  was  150  feet,  and  above  its  northern  end  about  200  feet. 

The  next  lower  level  of  Lake  Agassiz,  which  is  recorded  by  the  Ossowa 
shore-line,  lacked  only  15  miles  of  reaching  to  Grand  Forks,  and  had  almost 
as  great  total  length  and  width  as  the  preceding.  Its  height  above  tlie 
south  ends  of  Lakes  Manitoba  and  Winnipeg  was  about  30  and  130  feet, 
respectively. 


220  THE  GLACIAL  LAKE  AGASSIZ. 

At  the  time  represented  by  the  Stonewall  beach,  lying  next  in  descend- 
ing order,  the  surface  of  Lake  Agassiz  was  10  to  20  or  25  feet  above  Lake 
Manitoba,  6  to  15  or  20  feet  above  Lake  Winnipegosis,  and  about  110  and 
140  feet,  respectively,  above  the  southern  and  northern  ends  of  Lake  Win- 
nipeg. It  yet  extended  nearly  40  miles  south  of  the  international  bound- 
ary, to  the  vicinity  of  the  mouth  of  Park  River. 

In  receding'  from  the  Stonewall  to  the  Niver-sdlle  sta^e  Lake  Agassiz 
sank  below  Lakes  Winnipegosis  and  Manitoba,  which  remain  as  two  of  the 
three  large  remnants  of  this  vast  body  of  water.  On  the  line  of  the  tram- 
way at  the  Grand  Rapids  of  the  Saskatchewan  Mr.  Tyrrell  reports  four 
beach  ridges  of  gravel  and  sand,  as  already  noted,  at  the  heights  of  850, 
805,  800,  and  790  feet  above  the  sea.  The  first  is  referable  to  the  Stone- 
wall stage,  and  the  three  others  to  the  Niverville  stage,  which  is  here 
compound,  apparently  on  account  of  intermittent  northward  uplifting  of 
the  country.  Mr.  Tyrrell  informs  me  that  the  Niverville  beach  on  Black 
Island,  in  the  southern  part  of  Lake  Winnipeg,  is  about  60  feet  above  the 
lake.  At  the  Grand  Rapids,  175  miles  northwest  from  Black  Island,  its 
three  ridges,  in  descending  order,  are  95,  90,  and  80  feet  above  the  lake, 
showing  that  there  was  a  northward  uplift  of  15  feet  along  this  distance 
during  the  Niverville  stage,  and  that  since  then  a  further  differential  tilting- 
of  about  20  feet  has  taken  place.  The  southern  end  of  the  Niver^^lle 
level  of  Lake  Agassiz  was  near  Morris,  Manitoba.  It  failed  to  reach  into 
the  United  States  by  a  distance  of  about  25  miles,  being  the  first  stage  of 
this  glacial  lake  that  lay  wholly  in  British  America,  and  it  was  the  latest 
stage  held  by  the  ice  barrier  and  recorded  by  a  well-marked  shore-line. 
Lake  Agassiz  at  this  time,  as  during  several  preceding  stages,  reached  far 
north  and  northeast  of  Lake  Winnipeg,  and  up  to  its  latest  year  it  may 
have  had  an  area  of  20,000  or  30,000  square  miles. 

Finally  the  I'etreat  of  the  ice-sheet  uncovered  the  land  across  Avhich 
the  Nelson  outflows  from  Lake  Winnipeg  to  Hudson  Bay.  The  existence 
of  the  glacial  lake  was  ended,  and  this  largest  of  the  great  lakes  of  Mani- 
toba was  added  to  the  number  of  its  present  representatives  or  descend- 
ants.    Dr.  Bell's  descriptions  of  the  outlet  of  Lake  Winnipeg  and  the 


THIRTY-ONE  SUCCESSIVE  SHOKE-LINES.  221 

topography  of  the  adjoining  country^  show  that  no  barrier  of  land  so  high 
as  the  Niverville  beach  can  have  been  removed  there  by  erosion.  The 
original  level  of  Lake  Winnipeg,  due  to  the  height  of  the  land  upon  which 
the  Nelson  River  began  to  cut  its  channel  in  its  present  course,  is  doubtless 
that  of  the  well-defined  beach  observed  by  Hind  between  the  mouths  of 
the  Winnipeg  and  Red  rivers,  having  "an  elevation  of  21  feet  above  the 
present  level  of  Lake  Winnipeg."^  Traces  of  this  shore-line  will  probably 
be  found  at  nearly  the  same  height  around  the  wliole  lake. 

SUCCESSIVE  SHORE-IilNES   OF  XiAKE  AGASSIZ. 

In  the  southern  part  of  the  area  of  this  glacial  lake,  within  75  miles 
northward  from  its  mouth  at  Lake  Traverse,  five  principal  beaches  have 
been  observed,  and  in  their  descending  order  have  been  named,  from 
towns  in  Minnesota  near  which  they  are  well  exhibited,  the  Herman,  Nor- 
cross,  Tintah,  Campbell,  and  McCauleyville  beaches.  These  shore-lines, 
however,  when  traced  farther  north,  are  found  to  become  double  or  mul- 
tiple. The  Herman  beach  in  the  vicinity  of  Maple  Lake,  Minnesota,  is 
divided  into  five  beaches,  four  besides  the  highest  having  been  formed 
when  the  rise  of  the  land,  with  the  slight  fall  in  the  level  of  Lake  Agassiz, 
amounted,  successively,  to  8,  15,  30,  and  45  feet  on  the  east  side  of  the  lake 
in  that  latitude.  Still  farther  to  the  north,  in  Manitoba,  we  find  seven 
beaches  corresponding  to  the  single  Herman  beach  at  the  southern  outlet. 
In  like  manner,  the  Norcross  and  Tintah  beaches  are  each  represented  at 
the  north  by  two,  and  the  Campbell  and  McCauleyville  beaches  each  by 
three  distinct  shore-lines,  separated  by  slight  vertical  intervals.  The  north- 
ern part  of  the  lake  has  thus  no  less  than  seventeen  shore-lines,  which  were 
successively  formed  from  the  highest  to  the  lowest  during  the  time  of  the 
southward  outflow  through  Lakes  Traverse  and  Big  Stone  and  the  Minne- 
sota River  to  the  Mississippi. 

After  the  lake  obtained  its  earliest  outlet  to  the  northeast,  sinking 
below  Lake  Traverse,  it  formed  fourteen  shore-lines.     The  first  three  of 

'  Chapter  II,  pp.  29  and  62. 

°  Narrative  of  the  Canadian  Eed  River  Exploring  Expedition  of  1857,  and  of  the  Assiniboine  and 
Saskatchewan  Exploring  Expedition  of  1858,  Vol.  1,  p.  122. 


222  THE  GLACIAL  LAKE  AGASSIZ. 

these  pass  near  Blauchard,  N.  Dak.,  and  thence  are  denominated  the 
Blanchard  beaches.  The  next  in  descending  order  is  the  Hillsboro  beach, 
the  succeeding-  two  are  the  Emerado  beaches,  and  the  two  next  lower  the 
Ojata  beaches,  named  similarly  from  other  towns  of  this  State.  The 
remaining  six  lower  beaches  are  named  from  localities  in  Manitoba.  In 
the  same  descending  order,  they  comprise  the  Gladstone,  Burnside,  Ossowa, 
Stonewall,  and  Niverville  beaches,  the  last  being  double.  There  are  thus 
in  total  thirty-one  separate  shore-lines  of  this  lake  in  the  northern  portion 
of  its  area  explored  by  me ;  and  all  of  them,  excepting  the  lowest,  extend 
south  of  the  international  boundary. 

DEPENDENCE    OF    THE    LAKE    EEVEES    ON    THE    EROSION    AND 

CHANGES    OF    OUTLETS. 

PROGRESS    OF    EROSION    BY    THE    RIVER    WARREN 

Through  the  greater  part  of  the  duration  of  Lake  Agassiz  its  outlet 
remained  constantly  in  one  position,  and  the  stream  of  its  overflow,  named 
the  River  Wai-ren,  eroded  during  that  time  the  remarkable  valley,  rather  to 
be  described  as  a  trough-like  channel,  mostly  1  to  2  miles  wide  and  150 
to  230  feet  deep,  which  is  now  occupied  by  Lakes  Traverse  and  Big  Stone 
and  the  Minnesota  River.  There  is  evidence,  however,  in  the  terraces  of 
modified  drift  along  the  Minnesota  Valley,  that  in  large  part  its  erosion 
was  efi'ected  in  preglacial  time  and  during  stages  of  retreat  and  readvance 
of  the  ice-sheet  previous  to  its  final  departure,  when  it  was  the  ban-ier  of 
this  glacial  lake.^  The  general  surface  of  the  moderately  undulating  diift 
sheet,  having  swells  10  to  25  feet  above  its  hollows,  which  stretches  away 
on  each  side  from  the  top  of  the  bluff's  inclosing  this  valley  at  Lakes 
Traverse  and  Big  Stone,  is  about  1,100  feet  above  the  sea,  and  the  heights 
of  these  lakes  at  their  low  stage  of  water  are,  respectively,  970  and  962 
feet.  Before  the  retreat  of  the  ice  uncovered  this  .tract,  a  channel  40  or 
50  feet  deep  probably  existed  here,  nearly  or  quite  continuous,  along  the 
course  that  was  taken  by  the  River  Warren  in  its  first  discharge  from 
the  incipient  Lake  Ag-assiz ;  for  this  level,  much  below  the  even  expanse 

'  "The  Minnesota  Valley  in  the  Ice  age,"  Proc,  A.  A.  A.  S.,  Vol.  XXXII,  for  1883,  pp.  213-231. 
Geology  of  Minnesota,  Vols.  I  and  II. 


EROSION  BY  THE  RIVER  WARREN,  223 

of  cli-ift  tlirough  which  the  river  flowed,  is  the  height  of  the  Herman  beach, 
which  was  the  shore  of  the  glacial  lake  at  an  early  stage  and  through  a 
long  time  ensuing.  The  somewhat  higher  Milnor  beach  appears  to  have 
been  due  to  the  temporary  barrier  interposed  at  first  by  the  delta  gi-avel 
and  sand  of  the  glacial  Sheyenne  River,  spread  wholly  across  the  southern 
end  of  the  lake  at  its  beginning.  Over  this  barrier,  to  the  west  of  the  line 
between  White  Rock  and  Wheaton,  the  River  Warren  flowed  for  a  short 
time  with  rapids,  speedily  cutting  it  down  20  or  25  feet  to  the  bed  of 
the  previously  existing  channel  along  the  distance  of  50  miles  above  the 
present  sites  of  Lakes  Traverse  and  Big  Stone.  This  channel,  whose  depth 
determined  the  level  of  the  Herman  beach  while  the  lake  expanded  -with 
the  recession  of  the  ice-sheet  even  to  southern  Manitoba,  was,  as  I  believe, 
a  vestige  of  a  preglacial  and  possibly  interglacial  river  course  not  wholly 
filled  by  the  drift  deposits.  Reasons  for  this  belief  are  sufficiently  stated 
in  the  memoir  on  the  Minnesota  Valley  before  referred  to,  and  in  the 
description  of  certain  remarkable  chains  of  lakes  in  Martin  County,  Minn.^ 

Nearly  all  the  changes  in  the  relative  heights  of  Lake  Agassiz  and  the 
basin  that  held  it,  by  which  the  Herman  beach  became  fourfold  and  even 
sevenfold  in  proceeding  northward,  must  be  ascribed  to  epeirogenic  uplifting 
of  the  land,  with  only  a  very  small  element  of  change  in  the  lowering  of 
the  lake  level  by  erosion  of  its  outlet.  The  southern  portion  of  this  shore- 
line, as  far  to  the  north  as  the  latitude  of  Moorhead  and  Fargo,  is  marked 
by  a  single  beach  ridge,  very  definite  in  form  and  course,  but  not  massive 
in  comparison  with  the  present  beaches  of  the  ocean  or  of  the  great  lakes 
tributary  to  the  St.  Lawrence,  the  Nelson,  and  the  Mackenzie.  While  Lake 
Agassiz  was  forming  the  Herman  beach,  erosion  probably  lowered  the  chan- 
nel of  the  River  Warren  and  the  level  of  the  lake  5  or  10  feet.  During 
the  same  time  a  much  greater  differential  northward  uplift,  presently  to  be 
considered,  was  in  progress. 

From  the  level  of  the  Herman  beach  to  that  of  the  Norcross  beach 
Lake  Agassiz  fell  somewhat  suddenly  15  or  20  feet.  As  this  change  of 
level  affected  the  southern  part  of  the  lake,  adjoining  its  mouth,  it  is  evi- 
dent that  between  the  dates  of  these  shore-lines  the  River  Warren  eroded 

I  Geology  of  Minnesota,  Vol.  I,  1884,  pp.  479-485. 


224  THE  GLACIAL  LAKE  AGASSIZ. 

its  bed  to  thiis  additional  depth.  Thi-ough  a  comparatively  long  time,  rep- 
resented by  the  Herman  beach,  this  large  outflowing  river,  bearing  the 
waters  supplied  by  the  progressive  glacial  melting  upon  a  vast  area,  had 
only  deepened  its  channel  slightly;  but  at  the  close  of  this  stage  the  divi- 
sion between  it  and  the  next  following  Norcross  stage,  though  doubtless 
only  a  short  interval  of  time,  was  marked  by  a  considerable  increase  of 
depth  of  the  channel.  Why  was  the  river  able  to  erode  so  much  faster 
then  than  during  the  time  of  formation  of  the  Herman  beach,  or  of  the 
Norcross  beach  afterward,  which  likewise  represents  a  nearly  stationary 
period  in  the  progress  of  erosion  of  the  Lake  Traverse  Valley?  The 
answer  which  seems  best  was  suggested  to  me  by  Mr.  G.  K.  Gilbert  in 
a  letter  dated  February  3,  1888,  as  follows: 

*  *  *  Eetreat  of  the  ice  modified  the  geoid,  and  perhaps  produced  also  a 
crustal  change,  and  in  consequence  the  baselevel  assumed  a  new  attitude  to  the  land. 
The  river  adjusted  its  grade  to  the  new  conditions,  and  then  remained  stationary  dur- 
ing the  formation  of  the  Norcross  beach. 

The  portion  of  Mr.  Gilbert's  explanation  which  we  must  appeal  to  is 
that  atti'ibuting  the  temporarily  rapid  erosion  to  a  crustal  change,  that  is,  to 
an  uplifting  of  the  region  about  the  mouth  of  Lake  Agassiz ;  and  this  mieets 
the  case  fully.  There  was,  however,  no  apparent  reason  why  the  region  of 
Lake  Traverse  or  the  Minnesota  Valley  should  be  thus  intermittently  ele- 
vated, so  far  as  we  can  directly  compare  the  change  with  the  process  of  the 
glacial  retreat;  and  to  what  extent  this  movement  affected  the  northern 
portions  of  the  lake  area  can  only  be  ascertained  by  very  exact  compari- 
son of  the  altitudes  of  the  lowest  Hennan  and  the  highest  Norcross  beaches. 

Rhythmic  stages  of  elevation  of  the  country  across  which  the  River 
Warren  flowed,  intervening  with  pauses  in  the  action  of  the  uplifting  forces, 
are  shown  in  succession  by  the  Norcross  beach,  to  which  the  erosion  from 
the  level  of  the  lake  at  the  later  part  of  its  formation  of  the  Herman  beach 
was  about  20  feet;  by  the  two  Tintah  beaches,  to  the  first  of  which  there 
was  further  erosion  of  about  15  feet,  and  a  similar  amount  more  to  the  sec- 
ond; by  the  Campbell  beach,  to  which  again  the  river  still  further  cut  down 
its  channel  15  or  20  feet;  and  by  the  McCauleyville  beach,  formed  by  the 
lake  when  its  channel  of  outlet  was  the  bed  of  Lake  Traverse,  once  more 


EHYTHMIC  UPLIFTS  AND  STAGES  OF  BEST.  225 

15  to  20  feet  below  its  preceding  level.  Each  of  these  beaches  records  a 
comparatively  long  pause  in  an  uplifting  of  the  land  adjoining  the  mouth 
and  outlet  of  Lake  Agassiz,  which  was  periodically  renewed  during  brief 
stages  of  somewhat  rapid  inci*ease  of  elevation  at  no  less  than  five  times 
while  Lake  Agassiz  outflowed  southward.  The  regularity  or  rhythm  in  the 
sequence  of  these  beaches,  and  their  division  by  nearly  equal  vertical  inter- 
vals, were  doubtless  produced  by  rhythmic  uplifts,  alternating  with  longer 
stages  of  nearly  complete  rest. 

In  total  the  rise  of  the  country  about  Lake  Traverse  appears  not  to 
have  exceeded  90  feet  during  the  time  of  existence  of  the  River  Warren, 
and  probably  it  was  less.  This  river  is  not  known  to  have  formed  alluvial 
deposits  along  its  course,  building  up  its  bed,  but  instead  was  apparently 
cutting  down  its  channel  throughout  the  whole  extent  of  the  valley  now 
occupied  by  Lakes  Traverse  and  Big  Stone  and  the  Minnesota  River,  finally 
flowing  at  Belle  Plaine,  in  the  lower  part  of  the  Minnesota  Valley,  proba- 
bly 150  feet  below  the  present  river  and  140  feet  below  low  water  in  the 
Mississippi'  at  St.  Paul.^  A  considerable  share  of  the  total  erosion  of  90' 
feet  from  the  Herman  to  the  McCauleyville  beach  is  therefore  probably 
attributable  to  the  descending  slope  and  ordinary  downward  cutting  of  the 
River  Warren,  independent  of  its  stages  of  faster  rate  when  the  southern 
part  of  the  basin  was  being  elevated.  While  these  five  slight  uplifts,  prob- 
ably together  not  exceeding  90  feet  and  perhaps  no  more  than  75  or  50 
feet,  took  place  at  the  south,  a  much  larger  number  of  elevatory  move- 
ments, mostly  of  similarly  small  amount,  to  be  presently  discussed,  raised 
the  northern  part  of  the  lake  basin  200  to  300  feet  or  more,  their  amount 
becoming  greater  from  south  to  north.  The  little  depths  that  the  River 
Warren  eroded  during  the  several  stationary  stages  of  the  southern  end  of 
the  lake  basin  harmonize  well  with  the  small  volume  of  the  beach  deposits 
and  with  the  scanty  amount  of  cliff'-cutting  and  other  wave  action  on  the 
shores,  all  attesting  the  brevity  of  the  time  required  for  the  work  done. 

1  "The  Minnesota  Valley  in  the  Ice  age,"  Proc,  A.  A.  A.  S.,  Vol.  XXXII,  for  1883,  pp.  227-231. 
MON  XXV 15 


226  THE  GLACIAL  LAKE  AGASSIZ. 

LATER    OUTLETS    NORTHEASTWAED. 

When  the  outlet  of  Lake  Agassiz  was  changed  and  an  avenue  of  dis- 
charge toward  the  northeast  was  obtained,  the  south  end  of  the  lake  at 
first  fell  only  15  feet  below  the  McCauleyville  beach  and  the  bed  of  Lake 
Traverse.  Its  numerous  stages,  recorded  by  the  shore-lines  of  the  Avhole 
tijne  of  northeastward  outflow,  until  the  retreat  of  the  ice-sheet  uncovered 
the  present  course  of  the  Nelson,  were  in  succession  each  lower  than  the 
preceding  by  the  following  amounts,  as  determined  mostly  by  leveling  on 
the  latitude  of  Gladstone,  Manitoba,  308  miles  north  of  Lake  Traverse  and 
84  miles  north  of  the  international  boundary:  The  first,  second,  and  thud 
Blauchard  beaches,  respectively,  about  20,  15,  and  15  feet;  the  Hillsboro 
beach,  12  or  15  feet;  the  Emerado  beach,  about  30  feet;  the  Ojata  beach, 
25  feet;  the  Gladstone  beach,  20  feet;  the  Bumside  beach,  again  20  feet; 
the  Ossowa  beach,  15  feet;  the  Stonewall  beach,  20  feet;  and  the  Niverville 
beach,  45  feet.  Thence  to  the  earliest  level  of  Lake  Winnipeg  there  was 
again  a  fall  of  about  45  feet,  and  erosion  by  the  Nelson  River  has  since 
lowered  this  lake  about  20  feet. 

As  soon  as  the  ice  upon  Hudson  and  James  bays  and  the  adjoining 
country  had  so  receded  as  to  give  to  Lake  Agassiz  an  outlet  lower  than  the 
River  Warren,  it  began  to  be  drained  in  that  direction,  perhaps  flowing  at 
first  across  the  watershed  between  the  Poplar  and  Severn,  and  later  along 
lower  courses,  including  the  canoe  route  by  the  Hill  and  Hayes  rivers. 
Each  of  its  successive  outlets  was  probably  eroded  to  a  considerable  depth, 
being  occupied  by  the  outflowing  river  during  the  time  of  formation  of  two 
or  more  beaches,  until  the  retreat  of  the  southeastern  border  of  the  portion 
of  the  ice-sheet  remaining  west  of  Hudson  Bay  finally  permitted  di-ainage 
to  take  the  course  of  the  Nelson,  the  ice-dammed  Lake  Agassiz  being  thus 
changed  to  Lake  Winnipeg.  The  northeastern  outflow  commenced  when 
the  lake  at  the  latitude  of  the  south  end  of  Lake  Winnipeg  stood  about 
1,000  feet  above  the  present  sea-level,  and  it  was  gradually  lowered  to  730 
feet,  when  the  Nelson,  between  its  successive  lakes,  began  to  erode  the 
shallow  channel  of  the  upper  part  of  its  course. 

Inspection  of  the  series  of  vertical  intervals  between  the  successive 
levels  of  the  lake  during  its  northeastern  drainage  suggests  that  probably 


NORTHEASTWARD  OUTLETS.  227 

the  earliest  outlet  in  that  direction  was  occupied  during-  the  time  of  the 
three  Blanchard  beaches  and  the  Hillsboro  beach,  the  channel  being  cut 
down  about  45  feet.  The  comparatively  large  interval  above  the  Emerado 
beach  may  be  supposed  to  imply  the  transfer  of  the  discharge  to  a  new 
outlet;  and  the  series-  of  smaller  intervals  separating  the  next  five  beaches 
may  indicate  that  they  all  were  formed  while  this  channel  was  being  cut 
down  about  100  feet.  Another  large  fall  of  the  lake,  to  the  Niverville 
beach,  which  is  compound  in  its  northern  part,  would  again  mark  the  occu- 
pation of  a  new  outlet.  This,  however,  was  soon  abandoned  for  the  still 
lower  course  of  the  Nelson.  Exact  heights  of  these  old  river  courses, 
crossing  present  lines  of  Avatershed,  and  the  depths  of  their  erosion,  will 
doubtless  be  determined  at  some  future  time  by  exploration  and  leveling, 
though  probably  not  until  after  many  years,  on  account  of  the  difficulty  of 
carrying  instrumental  surveys  through  that  wooded  and  uninhabited  region. 

DEPENDEIS^CE   OF   LAKE   LEVELS   ON  EPEIROGENIC  ELEVATION.' 

The  five  or  six  distinct  beaches  that  were  formed  by  the  southern  part 
of  Lake  Agassiz  during  its  outflow  southward  are  represented  in  the  north- 
ern part  of  its  basin  by  seventeen  separate  shore-lines,  which  are  marked 
by  definite  beach  ridges.  The  individual  beaches  at  the  south,  being 
traced  northward,  become  double  or  triple,  and  the  highest  or  Hei'man 
beach  expands  into  seven  successive  shore-lines.  During  the  earlier  years 
of  my  exploration  of  this  glacial  lake  I  believed  that  this  duplication  and 
multiplication  of  the  beaches  observed  in  advancing  from  south  to  north 
was  referable  to  the  diminution  of  the  attraction  of  the  ice-sheet  as  its  final 
melting  progressed.  Gravitation  of  the  lake  toward  the  vast  mass  of  the 
ice,  and  its  decrease  with  the  glacial  recession,  I  then  supposed  to  be  ade- 
quate to  explain  the  observed  northward  ascent  of  the  beaches,  amounting 
for  the  highest  Herman  beach  to  5  or  6  inches  per  mile  for  its  first  50  miles 
at  the  south,  but  thence  increasing  northward  to  1  foot  and  1^  feet  per 
mile;  for  the  succeeding  beaches,  of  gradually  diminishing  amount;  and  for 
the  McCauleyville  beach,  the  latest  formed  during  the  southward  outflow, 

'  For  the  detinition  of  this  term,  proposed  by  Gilbert,  see  page  103. 


228  THE  GLACIAL  LAKE  AGASSIZ. 

ranging  from  1  inch  per  mile  at  the  south  to  about  2^  inches  per  mile  from 
the  international  boundary  to  the  latitude  of  Gladstone. 

With  further  exploration  and  study,  including  the  portion  of  the  lake 
area  examined  by  me  in  Manitoba,  I  became  convinced  that  this  explana- 
tion is  inapplicable  to  the  problem,  because  the  highest  beach  of  the  Her- 
man series  (formed  contemporaneously  with  the  six  large  deltas  which  were 
dependent  for  their  fomiation  on  the  accompanying  retreat  of  the  ice-sheet 
supplying  their  sand  and  gravel)  is  found  to  be  continuous  along  an  extent 
of  nearly  250  miles  from  south  to  noith,  reaching  from  Lake  Traverse  at 
least  to  Thornhill,  in  Manitoba,  across  an  area  which  has  several  prominent 
moraines  of  recession,  denoting  important  stages  of  decrease  of  the  ice- 
sheet.  These  moraines  extend  to  the  borders  of  Lake  Agassiz,  and  the 
ice  front  at  the  time  of  then-  formation  traversed  the  lake  basin.  There- 
fore, if  diminution  of  the  ice-attraction  Avere  the  principal  cause  of  the 
changes  of  the  levels  of  the  lake,  we  should  expect  the  highest  beach  to 
cease  at  the  successive  morainic  belts,  and  another  somewhat  lower  to  take 
its  place  thence  northward. 

For  aid  in  the  investigation  of  this  and  other  movements  of  elevation 
of  the  land  following  the  departure  of  ice-sheets  and  the  evaporation  of 
Lake  Bonneville,  Mr.  R.  S.  Woodward,  of  the.  United  States  Geological 
Sm'vey,  made  a  careful  mathematical  computation  of  the  effects  of  such 
masses  of  matter  fonnerly  existing  upon  portions  of  the  earth's  siu-face  to 
deform  the  geoid  or  level  of  the  water  of  lakes  or  the  sea.^  His  result, 
agreeing  approximately  ^with  conclusions  from  similar  computations  by 
European  mathematicians  and  physicists,  shows  that  the  North  American 
ice-sheet,  with  its  known  area  and  its  maximum  probable  thickness,  would 
be  capable  of  drawing  the  level  of  Lake  Agassiz  upward  to  the  north  not 
more  than  a  quarter,  or  perhaps  no  more  than  an  eighth  or  tenth,  as  much 
as  the  ascent  of  the  Herman  beach.  It  is  thus  evident  that  we  must  look 
to  some  other  cause  for  explanation  of  these  changes  of  level,  and  this  is 
found  in  a  differential  uplifting-  of  the  lake  basin,  increasing  in  amount 
from  south  to  north  upon  all  the  area  where  we  have  determined  the 
heights  of  the  beaches. 

'  U.  S.  Geol.  Survey,  Sixth  Annual  Report,  pp.  291-300 ;  and  Bulletin  No.  48,  "  Ou  the  form  and  posi- 
tion of  the  sea-level." 


ICE  ATTRACTION  AND  EPEIKOGBNIC  MOVEMENTS.  229 

The  departure  of  the  sheets  of  land  ice  which  spread  drift  formations 
over  the  northern  part  of  North  America,  northwestern  Europe,  and  Pata- 
gonia, was  in  each  of  these  great  and  widely  separated  areas  attended  by 
a  depression  of  the  land.  While  each  of  these  ice-sheets  was  melting 
away,  the  land  on  which  it  had  lain  was  somewhat  lower  than  now,  and  its 
coasts  were  partially  submerged  by  the  sea.  These  are  the  only  extensive 
regions  of  the  earth  which  have  lately  borne  ice-sheets  that  have  now 
melted,  and  it  seems*  to  be  a  most  reasonable- inference  that  the  vast  weight 
of  their  burdens  of  ice  was  an  important  element  in  the  causes  of  their 
subsidence.  Since  the  disappearance  of  their  ice-sheets,  each  of  these  con- 
tinental areas  has  been  uplifted,  probably  in  large  measure  because  of  the 
withdrawal  of  the  ice-load.  .  In  Europe  these  epeirogenic  movements  of 
depression  and  reelevation  seem  to  have  been  more  nearly  proportionate  to 
the  volume  and  extent  of  tlae  ice-sheet  than  on  our  continent.  Both  in 
North  and  South  America,  other  great  epeirogenic  movements,  affecting 
large  areas  which  were  never  glaciated,  have  been  in  progress,  apparently 
during  the  same  time  and  in  close  association  with  the  oscillations  of  the 
glaciated  regions.  In  another  chapter,  treating  more  fully  of  the  causes  of 
the  changes  in  level  of  the  beaches  of  Lake  Agassiz,  these  complex  move- 
ments of  our  continent  and  other  parts  of  the  world  during  the  Quaternary 
era  will  be  reviewed  for  the  purpose  of  learning,  -if  possible,  how  and  why 
such  subsidences  and  uplifts  of  great  areas  take  place. 

At  present  we  need  only  to  inquire  what  were  the  amounts  of  depres- 
sion of  the  basin  of  Lake  Agassiz  and  of  contiguous  parts  of  this  continent, 
since  these  would  affect  the  history  of  this  lake  in  its  reduction  from  its 
highest  level  to  its  lower  shore-lines  and  to  Lake  Winnipeg;  and  what  was 
the  manner  of  the  reelevation,  whether  by  regular  and  continued  move- 
ment, or  by  intermitteiit  uplifting  and  stages  of  repose,  and  whether  the 
basin  was  uplifted.dififerentially  as  a  whole  or  in  successive  poi'tions. 

Depression  of  the  continent  shotvn  hy  coastal  submergence. — Answering  the 
first  part  of  these  inquiries  so  far  as  we  may  by  the  known  extent  of  oceanic 
submergence  of  the  land  when  it  became  uncovered  from  the  ice,  we  have 
the  testimony  of  marine  fossils  in  beds  overlying  the  glacial  drift,  which 
show  that  the  country  southwest  of  Hudson  and  James  bays  then  stood 


230  THE  GLACIAL  LAKE  AGASSIZ. 

300  to  500  feet  below  its  present  level;  that  the  Ottawa  basin  was  de- 
pressed 400  to  500  feet;  the  St.  Lawrence  Valley,  about  250  feet  at  the 
mouth  of  Lake  Ontario,  at  least  560  feet  at  Montreal,  and  375  feet  opposite 
the  Saguenay ;  and  the  country  bordering  the  Gulf  of  St.  Lawrence,  about 
200  feet  at  the  Bay  of  Chaleurs,  with  diminishing-  amount  thence  to  the 
east  and  south,  ceasing  in  Nova  Scotia  and  southeastern  Massachusetts.  In 
the  Mackenzie  basin,  evidences  of  marine  submergence  since  the  Glacial 
period  have  not  been  found;  but  they  are  discovered,  up  to  heights  of  100 
to  300  feet,  on  the  Pacific  coast  of  the  di'ift-bearing  area.  It  is  probable, 
however,  that  these  elevations  of  marine  deposits  are  not  full  measurements 
of  the  depression  under  the  ice-load.  The  nearly  complete  uplifting  of  the 
basin  of  Lake  Agassiz  while  the  ice-sheet  was  retreating  from  it  and  was 
still  the  barrier  of  the  waning  glacial  lake  proves  that  the  reelevation 
closely  followed  the  departure  of  the  ice,  and  suggests  that  in  the  districts  of 
these  marine  beds  some  uplifting  may  have  been  done  "while  the  ice  above 
was  becoming  thin,  but  had  not  wholly  disappeared,  or  at  least  before  its 
retreat  had  opened  ways  of  ingress  for  the  sea. 

Depression  and  reelevation  of  the  hasin  of  Lake  Agassiz  shown  hy  differen- 
tially uplifted  beaches. — If  we  next  seek  a  measure  of  the  subsidence  of  the 
basin  of  Lake  Agassiz  while  it  was  ice-burdened,  no  marine  beds  above 
the  drift  in  this  district  can  aid  in  giving  an  answer,  but  we  must  look 
to  the  known  amount  of  northward  uplifting  of  the  once  level  beaches,  and 
from  this  differential  elevation  it  seems  well-nigh  sure  that  the  maximum 
depression  which  this  basin  i;nderwent  failed  to  sink  its  lowest  part,  the 
shallow  bed  of  Lake  Winnipeg,  to  the  sea-level.  The  central  and  northern 
portion  of  the  area  of  Lake  Agassiz,  where  the  great  lakes  of  Manitoba  are 
now  outspread,  was  depressed  apparently  400  or  500  feet,  carrying  the  pres- 
ent shores  of  Lake  Winnipeg  down  to  an  altitude  of  only  300  or  200  feet 
above  the  sea;  but  the  bed  of  this  lake,  which  is  less  than  100  feet  deep, 
was  still  above  the  ocean.  The  amount  of  subsidence  here  is  thus  found 
to  be  harmonious  with  that  of  other  parts  of  our  glaciated  area  which  bor- 
dered the  oceans  and  Hudson  Bay.  As  a  whole,  the  ice-enveloped  portion 
of  the  continent  is  seen  to  have  sunk  slightly  more  in  its  central  region  than 
on  its  boundaries.     The  vertical  extent  of  the  maximum  known  depression, 


OUTLET  TO  MACKENZIE  EIVER  IMPROBABLE.  231 

detennined  by  marine  fossils  of  the  Champlain  epoch  and  by  the  incUned 
beaches  of  this  glacial  lake,  ranged  from  no  subsidence  in  the  greater 
part  of  Nova  Scotia  to  probably  600  feet  at  Montreal,  nearly  the  same  at 
Ottawa  and  about  James  Bay,  approximately  500  feet  in  Manitoba,  none 
or  little  on  the  Mackenzie,  and  from  300  to  100  feet,  probably  decreasing 
from  north  to  south,  on  the  shores  of  the  Queen  Charlotte  Islands  and 
British  Columbia. 

Some  addition  to  these  figures,  but  probably  nowhere  exceeding  a 
quarter  or  third  more,  is  required  to  give  the  earlier  extreme  extent  of  the 
subsidence  of  the  ice-weighted  land,  thus  including  its  rise  before  the  ice 
above  had  wholly  melted,  or  before  the  sea  was  admitted  to  Hudson  and 
James  bays,  and  to  the  St.  Lawrence,  Lake  Champlain,  and  Ottawa  val- 
leys. But  this  small  added  amount  was  offset  in  part  or  entirely  by  the 
effect  of  gravitation,  which  raised  the  levels  of  the  ocean  and  lakes  toward 
the  ice-sheet.  These  two  causes  of  changing  levels  acted  in  conjunction 
in  their  relationship  to  the  series  of  shore-lines  of  Lake  Agassiz,  and  to  the 
position  and  course  of  its  outlets  after  it  fell  below  the  channel  at  Lake 
Traverse;  but  the  effect  of  ice  attraction  must  be  deducted  from  the  total, 
if  we  ask  the  extent  of  epeirogenic  subsidence  and  reelevation,  which  there- 
fore are  probably  closely  expressed  in  the  figures  before  stated,  having  a 
maximum  of  500  to  600  feet. 

ImprohaUe  hypothesis  of  an  outlet  from  Lake  Agassiz  to  the  Mackenzie 
Eiver.—We  may  therefore  dismiss  as  untenable  the  supposition  that  the 
outflow  of  Lake  Agassiz,  after  falling  below  Lake  Traverse  and  the  Mc- 
Cauleyville  beach,  and  being  still  obstructed  from  going  to  Hudson  Bay 
by  the  presence  of  a  large  remnant  of  the  ice-sheet  there,  could  have 
passed  for  a  time  across  the  divide  between  the  Churchill  and  Athabasca 
rivers,  thus  being  discharged  into  the  Mackenzie  and  the  Arctic  Ocean. 
Such  northwestward  outflow  would  have  crossed  the  present  watershed 
near  the  Methy  portage,  or  by  way  of  Wollaston  or  Hatchet  Lake,  which 
has  two  outlets,  one  to  the  Churchill  and  the  other  to  the  Athabasca.  The 
altitude  of  tlie  summit  of  the  Methy  portage,  according  to  Richardson's 
observations,  with  correction  for  the  now  better-known  heights  of  Lake 
Winnipeg  and  the  Saskatchewan,  appears  to  be  about  1,750  feet  above  the 


232  THE  GLACIAL  LAKE  AGASSIZ. 

sea;  and  Methy  Lake,  at  the  head  of  a  series  of  lakes  and  connecting 
streams  tributary  to  the  Churchill,  is  about  50  feet  lower.  According  to 
Dr.  Robert  Bell,  "there  is  said  to  be  a  continuous  watercourse"  near  this 
23ortag-e,  passing  from  the  Clearwater,  a  branch  of  the  Athabasca,  into  the 
Churchill  basin ;  ^  but  its  height  forbids  the  inference  that  the  waters  of 
Lake  Agassiz  ever  outflowed  there,  for  a  subsidence  of  more  than  700  feet 
would  be  required  to  reduce  Methy  Lake  and  the  divide  in  its  vicinity  to 
the  level  of  Lake  Traverse.  Instead,  as  was  stated  on  page  64,  it  is  my 
belief  that  this  channel  was  the  outlet  of  a  lake  in  the  Athabasca  basin, 
dammed  b}'  the  barrier  of  the  receding  ice-sheet  on  the  north  and  thus 
made  tributary  to  Lake  Agassiz.  The  other  pass  over  the  watershed,  by 
the  way  of  Hatchet  and  Jackfish  lakes,  situated  300  to  375  miles  north- 
east of  the  Methy  j^ortage,  is  probably  1,300  or  1,400  feet  above  the  sea, 
and  presents  nearly  equal  difficult)'  to  the  hypothesis  of  an  outlet  from  the 
Winnipeg  basin  to  the  Mackenzie;  but  again  there  is  much  likelihood  that 
this  course  also  served,  at  a  later  date,  as  an  important  avenue  of  inflow  to 
Lake  Agassiz  from  the  Athabasca  glacial  lake. 

Probable  hypothesis  of  the  discharge  from  the  northeastward  outlet  being 
tributary  successively  to  the  Mississippi  and  Hudson  rivers. — When  the  dis- 
charge by  the  River  Warren  ceased,  the  new  outlet  flowed  northeastward. 
Perhaps,  as  before  stated,  it  turned  back  for  some  time  to  the  south  along 
the  border  of  the  waning  ice-sheet,  and  thus  still  passed  into  the  Mississippi 
by  the  way  of  Lakes  Superior  and  Michigan.  Stranger  yet,  tlirough  the 
effect  of  subsidence,  which  greatly  modified  the  conditions  of  di-ainage  in 
the  Champlain  epoch,  as  pointed  out  by  Mr.  Gilbert,^  this  overflow,  pre- 
vented by  the  ice-barrier  from  going  in  the  direction  of  the  land  slope  to 
Hvidson  Bay,  may  have  been  later  carried  into  the  Atlantic  by  the  Mohawk 
and  Hudson  rivers;  or,  at  a  still  later  stage,  it  may  have  taken  its  course 
past  the  mouth  of  Lake  Ontario  to  the  sea  near  the  head  of  the  greatly 
enlarged  Gulf  of  St.  Lawrence,  which  then  filled  the  St.  Lawrence  Valley, 
the  basin  of  Lake  Champlain,  and  the  Ottawa  Valley  to  Allumette  Island 

'  Bulletin,  G.  S.  A.,  Vol.  I,  1890,  p.  291. 

'"'The  History  of  the  Niagara  River,"  Sixth  Annual  Report  of  the  Commissioners  of  the  State 
Reservation  at  Niagara,  for  the  year  1889,  pp.  61-84,  with  maps  (also  in  the  Annual  Report  of  the 
Smithsonian  Institution,  1890,  pp.  231-257). 


HYPOTHESIS  OF  NORTHEASTWARD  OUTFLOW.  233 

or  higher/  Perhaps,  last  of  all,  before  the  glacial  recession  admitted  the 
sea  to  Hudson  Bay,  this  discharge  from  Lake  Agassiz,  flowing  through  a 
great  glacial  lake  in  the  southwestern  part  of  the  basin  of  Hudson  and 
James  bays,  would  find  its  lowest  and  final  outlet  to  the  south  by  the  way 
of  Lakes  Abittibi,  des  Quinae,  and  Temiscaming,  then  entering  the  Ottawa 
arm  of  the  Gulf  of  St.  Lawrence.  It  seems  even  possible  that  the  vicissi- 
tudes of  the  changing  courses  of  drainage  produced  by  the  gradual  retreat 
of  the  ice  may  have  included  for  the  outflow  from  Lake  Agassiz,  after 
it  began  to  pass  first  northeastward,  all  of  these  four  ultimate  routes ;  first, 
by  Chicago  to  the  Mississippi;  second,  by  the  glacial  Lakes  Algonquin, 
Lundy,  and  Iroquois,  and  the  Mohawk  and  Hudson  rivers,  to  the  Atlantic; 
third,  by  the  lake  portion  of  this  route,  and  perhaps  for  some  short  time  by 
Lake  Nipissing  and  the  Mattawa  River,  to  the  head  of  the  Gulf  of  St.  Law- 
rence, then  filling  the  St.  Lawrence  Valley  and  a  part  of  the  Ottawa  basin; 
and  fourth,  by  Lake  Abittibi,  crossing  the  lowest  point  of  the  watershed 
between  James  Bay  and  the  St.  Lawrence.  The  known  epeirogenic  subsi- 
dence of  the  Champlain  epoch  and  the  probable  manner  of  recession  of 
the  ice  border  from  south  to  north  make  each  and  all  of  these  courses, 
diverting  the  northeastward  outflow  to  the  south,  far  more  probable  than 
either  of  the  coiu'ses  before  considered  by  which  this  glacial  lake  might  be 
supposed  to  send  its  overflow  to  the  Mackenzie. 

Division  of  the  ice-sheet  into  parts  east  and  ivest  of  Hudson  Bay. — It  seems 
to  me  most  probable,  however,  that  long  before  the  complete  departure  of 
the  ice-sheet  it  became  melted  in  twain  by  the  laving  action  of  Lake  Agas- 
siz and  of  a  great  glacial  lake  in  the  southwestern  and  southern  part  of  the 
basin  of  Hudson  Bay,  and  on  its  other  side  by  the  sea  washing  its  ice-cliffs 
in  Hudson  Strait  and  the  northern  part  of  Hudson  Bay,  so  that  the  latest 
general  glaciation  of  our  continent  was  confined  to  two  areas,  one  east  and 
the  other  west  of  this  vast  mediterranean  sea.  Several  of  the  lower  shore- 
lines of  Lake  Agassiz,  formed  during  its  northeastward  drainage,  if  not 
all  of  them,  doubtless  mark  levels  of  outlets  which  flowed  into  this  inland 
sea,  until  the  northward  recession  of  the  remnant  of  the  ice-sheet  on  its 
west  side  laid  bare  the  course  of  the  Nelson.     Careful  collection  and  study 

'  Am.  Jour.  Sci.  (3).  Vol.  XLIX,  pp.  1-18,  with  map,  Jan.,  1895. 


234  THE  GLACIAL  LAKE  AGASSIZ. 

of  observations  of  the  beariugs  of  glacial  striae  on  all  portions  of  Canada 
to  the  far  north,  and  examination  of  the  lowest  points  of  watersheds  as  to 
their  glacial  river  courses,  will  l)e  the  means  of  displacing  these  specula- 
tions by  definite  knowledge  and  proofs  of  what  were  the  fortunes  of  the 
departing  ice-sheet  and  of  the  late  outlets  of  this  lake.^ 

Amount  of  differential  elevation  between  Lake  Traverse  and  Gladstone. — 
How  the  Red  River  Valley  and  the  lake  country  of  Manitoba  were  uplifted 
from  the  late  glacial  or  Champlain  depression  is  told  by  the  inclination  of 
the  Lake  Agassiz  shore-lines.  So  far  as  exploration  and  determination 
of  the  heights  of  the  beaches  have  extended,  including  both  my  own  and 
Mr.  Tyrrell's  work,  there  is  found  to  be  a  northward  ascent  of  the  old  lake 
levels,  greatest  in  amount  along  the  earlier  and  higher  beaches,  and  dimin- 
ishing almost  to  horizontality  in  the  latest  and  lowest.  Comparing  the 
heights  of  the  beaches  at  or  near  the  mouth  of  the  lake  with  their  heights 
about  300  miles  to  the  north,  on  the  latitude  of  Gladstone,  which  is  near 
the  northern  limit  of  my  observations,  it  is  seen  that  the  epeirogenic  uplift- 
ing of  this  part  of  the  lake  basin,  increasing  gradually  from  south  to  north, 
and  the  fall  of  the  lake  surface,  also  greatest  at  the  north  on  account  of  the 
decreasing  effect  of  gravitation  toAvard  the  diminishing  and  receding  ice- 
sheet,  were  together  approximately  265  feet  in  this  distance,  averaging 
nearly  1  foot  per  mile,  after  the  formation  of  the  second  Herman  beach, 
which  is  the  highest  found  on  that  latitude.  Of  this  combined  uplift  of  the 
land  and  fall  of  the  lake,  about  80  feet  had  taken  place  before  the  forma- 
tion of  the  Norcross  beach;  50  feet  more  before  the  upper  Tintah  beach; 
about  45  feet  more  before  the  Campbell  beach;  and  again  some  25  feet 
more  before  the  McCauleyville  beach;  leaving  only  65  feet  of  the  whole 
265  feet  of  changed  level  to  take  place  after  the  lake  began  to  outflow 
northeastward,  and  it  appears  that  all  but  about  20  feet  of  this  remaining 
change  had  been  accomplished  before  the  formation  of  the  lowest  or  Niver- 
ville  beach.  While  the  ice  was  departing  from  the  country  and  still  was 
the  barrier  of  the  lake,  this  part  of  its  basin  was  uplifted  nearly  to  its 

'  Since  this  paragrapli  was  written  the  explorations  of  Mr.  ,J.  B.  Tyrrell  in  the  region  from  Lake 
Athabasca  northeast  to  the  Chesterfield  Inlet  of  Hudson  Bay  (Geol.  Magazine,  IV,  Vol.  I,  pp.  394-399, 
Sept.,  1894)  have  given  much  support  to  this  opinion.  See  also  Professor  Chamberlin"s  map  of  the 
North  American  ice-sheet,  with  indications  of  its  centers  and  currents  of  outflow,  in  J.  Geikie's  Great 
Ice  Age,  third  ed.,  1894,  PI.  XIV. 


INCLINATION  OF  BEACHES.  235 

present  altitude,  and  the  total  amount  of  the  differential  elevation  in  this 
extent  of  300  miles,  after  subtracting'  a  quarter  part  for  the  probable  or 
possible  effect  of  ice  attraction,  was  about  200  feet. 

Alternate  stages  of  elevation  and  rest. — The  considerable  number  of  defi- 
nite additional  shore-lines  observed  in  proceeding  to  the  north  indicates,  like 
the  stages  of  erosion  by  the  River  Warren  between  the  times  of  formation 
of  the  beaches  near  Lake  Traverse,  that  there  were  periods  of  compara- 
tively rapid  uplifting-  which  alternated  with  others  of  repose  or  of  very  slow 
progress  of  the  general  epeirogenic  movement.  Vertical  uplifts  of  10  to 
20  or  25  feet  were  many  times  repeated,  and  were  separated  by  longer 
intervals  of  rest.  But  the  initiation  of  these  stages  of  uplift  was  delayed 
until  long-  after  Lake  Agassiz  began  to  exist.  The  ice-sheet  had  retreated 
from  Lake  Traverse  to  Manitoba,  and  three  or  four  conspicuous  moraines 
of  recession  had  been  formed,  while  the  lake  level  reposed  undisturbed 
during-  the  formation  of  the  first  and  highest  beach  of  the  Herman  series 
and  the  accumulation  of  the  contemporaneous  deltas.  Such  tardiness  in 
the  beginning-  of  the  elevation  of  this  area,  as  it  is  recorded  by  the  inclined 
shore-lines,  implies,  and,  indeed,  makes  it  almost  certain,  that  very  little 
uplifting,  if  any,  had  taken  place  during  the  time  of  melting-  away  of  the 
ice  above.  If  the  restoration  of  the  land  to  its  wonted  height  had  already 
begun  under  the  thinned  edge  of  the  ice,  it  would  probably  have  gone 
forward  more  promptly,  while  the  Red  River  Valley  was  being  gradually 
occupied  by  Lake  Agassiz,  following-  upon  the  retreat  of  the  ice-front. 

Later  and  greater  inclination  of  beaches  along  the  base  of  Biding  and  Duck 
mountains. — On  the  area  of  300  miles  extent  from  south  to  north  between 
the  mouth  of  the  lake  and  Grladstone,  the  epeirogenic  differential  uplift  was 
mostly  done  before  the  times  of  formation  of  the  Campbell  and  McCauley- 
ville  beaches,  the  last  two  belonging  to  the  southward  outlet;  but  farther  to 
the  north,  within  the  area  at  the  base  of  the  escarpment  of  Riding  and  Duck 
mountains,  where  Mr.  Tyrrell  has  mapped  the  beaches  of  this  lake  and 
determined  their  heights,  a  very  important  differential  elevation,  amounting 
to  about  3  feet  per  mile  along  a  distance  of  50  miles  between  Valley  and 
Duck  rivers — that  is,  between  latitudes  51°  15'  and  52°  north — took  place 
after  the  Campbell  and  McCauley  ville  beaches  were  formed,  since  they  are 


236  THE  GLACIAL  LAKE  AGASSIZ. 

thus  remarkably  changed  from  their  original  horizontality.  It  is  clearly 
shown  here  that  the  uplifting  was  not  uniformly  proportionate  and  regular 
for  the  whole  area  of  Lake  Agassiz.  The  chief  movements  of  elevation  of 
its  southern  and  central  part,  as  far  to  the  north  as  Gladstone,  seem  not  to 
have  extended  farther,  at  least  in  their  full  proportion.  The  district  next 
to  the  north  along  an  extent  of  120  miles  to  Pine,  Duck,  and  Swan  rivers, 
at  the  north  end  of  Duck  Mountain,  was  perhaps  only  so  far  disturbed  by 
these  movements  as  was  necessitated  to  connect  the  rise  of  the  country 
on  the  latitude  of  Gladstone  with  the  continuing  condition  of  maximum 
subsidence  on  the  latitude  of  the  lower  part  of  the  Saskatchewan  and 
the  north  end  of  Lake  Winnipeg.  But  there  ensued  in  this  district,  after  the 
date  of  the  Campbell  beach,  a  great  differential  elevation,  giving  to  these 
late  shore-lines  two  to  three  times  more  northward  ascent  than  that  of 
the  Herman  beach  from  Lake  Traverse  to  Gladstone;  and  the  total  change 
in  level  of  the  highest  observed  beach,  probably  representing  the  upper 
Norcross  stage,  situated  at  Pine  River,  on  latitude  51°  50'  to  52°  north,  is 
approximately  400  feet  as  compared  with  this  shore-line  at  Lake  Traverse, 
about  420  miles  distant  to  the  south.  Nearly  the  whole  uplift  of  the 
northern  part  of  the  basin  was  accomplished,  however,  while  the  ice-sheet 
was  still  a  ban-ier  of  the  lake,  for  the  Niverville  beach  at  the  Grand  Rapids 
of  the  Saskatchewan  is  only  slightly  higher  than  on  the  Red  River,  250 
miles  to  the  south. 

Bevieu'  of  the  epeirogenic  uplifting. — After  the  recession  of  the  ice  from 
its  vicinity,  the  mouth  of  Lake  Agassiz  by  the  River  Warren  was  uplifted 
apparently  at  least  50  or  75  feet,  and  perhaps  as  much  as  90  feet,  by  several 
small  stages  of  elevation,  separated  by  comparatively  long  pauses.  Thence 
to  the  latitude  of  Gladstone,  in  a  distance  of  300  miles  northward,  such 
small  uplifts,  increasing  in  number  and  in  aggregate  vertical  amount  from 
south  to  north,  raised  the  lake  basin  in  southern  Manitoba  not  less  than  200 
feet;  and,  in  combination  with  the  fall  of  the  lake  level  northward,  due  to 
decreasing  ice  attraction,  the  change  in  level  was  265  feet.  To  these  figures 
we  must  add  the  uplift  of  the  Lake  Traverse  region,  which  was  probably 
between  50  and  100  feet,  to  obtain  the  total  epeirogenic  elevation  at 
Gladstone.     Later  epeirogenic  movements  of  the  same  kind  raised  a  more 


EEVIEW  OF  EPBIROGBmO  UPLIFTING.  237 

northern  part  of  the  basin,  on  the  latitude  of  52°  north,  about  400  feet,  if 
we  neglect  the  fall  of  the  lake  level,  in  comparison  with  Lake  Traverse. 
At  the  same  time,  or  possibly  still  later,  the  northern  end  of  the  area  of 
Lake  Agassiz  and  the  adjoining  portion  of  the  Churchill  basin  were  uplifted 
a  similar  amount.  Last  of  all,  when  Lake  Winnipeg  and  the  Nelson  River 
had  come  into  existence,  the  shores  of  Hudson  and  James  bays  were  raised 
300  to  500  feet  from  their  temporary  postglacial  marine  submergence. 

The  elevation  of  the  eastern  shore-lines  of  Lake  Agassiz,  in  Minnesota, 
exceeded  that  of  the  western  shores,  in  North  Dakota;  and  the  ratio  of  this 
eastward  ascent  of  the  old  lake  levels  to  their  doubly  greater  northward 
ascent  implies  that  the  tilting  of  this  area  was  from  south-southwest  to 
north-northeast.  Again,  at  the  north  end  of  Duck  Mountain,  the  west-to- 
east  portions  of  beaches  observed  by  Mr.  Tyrrell,  between  the  Swan  and 
Duck  rivers,  show  a  similar  eastward  ascent,  about  half  as  much  as  the 
northward  rise  along  the  eastern  base  of  this  highland.  It  thus  appears 
true  of  the  greater  tilting  of  that  northern  district  also,  after  the  formation 
of  the  Campbell  beach,  that  its  maximum  ascent  was  toward  the  north- 
northeast;  but,  like  the  elevation  between  Lake  Traverse  and  Gladstone, 
this  movement  was  doubtless  of  limited  extent,  so  that  the  country  adjoin- 
ing Hudson  Bay  retained  nearly  or  quite  its  maximum  depression  until  the 
somewhat  later  time  ^^•hen  the  sea  was  admitted  to  that  basin. 

MOIiliUSCAN"    FAUKA    OF    LAKE    AGASSIZ. 

Fossils  have  been  found  in  the  deposits  of  Lake  Agassiz  at  two  locali- 
ties. They  are  all  fresh-water  shells  of  species  now  living  in  this  district, 
occurrinff  in  beach  ridffes  where  excavations  have  been  made  to  obtain 
sand  for  masons'  use.  The  Campbell  beach,  about  6  miles  southwest  of 
Campbell,  Minn.,  at  an  elevation  approximately  985  feet  above  the  sea,  has 
thus  yielded  shells  of  TJnio  ellipsis  Lea,  a  common  species  of  the  Upper 
Mississippi  region.  In  the  Gladstone  beach,  a  half  mile  northeast  of  Glad- 
stone, Manitoba,  about  875  feet  above  the  sea  and  165  feet  above  Lake 
Winnipeg,  four  species  occur  in  considerable  abundance  from  2  to  4  feet 
below  the  surface,  namely,    Unio  luteolus   Lamarck,   Sph(Brium  striatinum 


238  THE  GLACIAL  LAKE  AGASSIZ. 

Lara.,  Sphcerium  sulcatum  Lam.,  and  (jryrauliis  parvus  Say.  These  species 
from  both  locahties  were  kindly  determined  hy  Prof.  R.  Ellsworth  Call, 
who  states  that  Unio  luteolus  is  one  of  the  most  widely  distributed  repre- 
sentatives of  the  genus,  its  range  being  from  Lake  Winnipeg  to  Texas,  east 
to  New  York,  and  west  to  Montana.  It  is  generally  abundant  in  Minne- 
sota. Both  these  species  of  Splicer'mm  are  reported  by  Dr.  Dawson  from 
the  Lake  of  the  Woods  and  Pembina  River;  and  the  first  is  the  most  com- 
mon species  of  its  genus  in  ]\Iinnesota,  while  its  range  northward  extends 
atJeast  to  Great  Playgreen  Lake  and  York  Factory,  where  it  has  been  col- 
lected by  Dr.  Bell.  The  Campbell  beach  was  formed  in  the  later  part  of 
the  time  of  the  lake's  southward  outflow;  and  the  Grladstone  beach  belouffs 
to  the  middle  portion  of  the  time  of  its  outflow  toward  the  northeast,  its 
south  end  being  then  about  90  miles  south  of  the  international  boundary. 

MEASUREMENTS    OF    TIME    SIIfCE    THE   GLACIAL    PERIOD. 

If  the  question  be  asked,  How  many  thousand  years  ago  did  the  reces- 
sion of  the  ice-sheet  take  place,  causing  Lake  Agassiz  to  fill  the  Red  Rive*' 
Valley  and  the  basin  of  Lake  Winnipeg?  a  reply  is  furnished  by  the  com- 
putations of  Prof.  N.  H.  Winchell,^  that  approximately  eight  thousand  years 
have  elapsed  during  the  erosion  of  the  postglacial  gorge  of  the  Mississippi 
from  Fort  Snelling  to  the  Falls  of  St.  Anthony;  of  Dr.  Edmund  Andrews,^ 
that  the  erosion  of  the  shores  of  Lake  Michigan,  and  the  resulting  accumu- 
lation of  dune  sand  drifted  to  the  southern  end  of  that  lake,  can  not  have 
occupied  more  than  seven  thousand  five  hundred  years;  of  Prof.  Gr.  Fred- 
erick Wright,^  that  streams  tributary  to  Lake  Erie  have  taken  a  similar 
length  of  time  to  cut  their  valleys  and  the  gorges  below  their  waterfalls; 
of  Mr.  G.  K.  Gilbert,*  that  the  gorge  below  Niagara  Falls  has  required  only 
seven  thousand  years  or  less;  and  of  Prof.  B.  K.  Emerson,^  on  the  rate  of 

'  Geology  of  Minnesota,  Fifth  Annual  Report,  for  1876;  and  Final  Report,  Vol.  II,  pp.  313-341. 
Quart.  Jour.  Geol.  Soc,  Vol.  XXXIV,  1878,  pp.  886-801. 

-Transactions  of  the  Chicago  Academy  of  Sciences,  Vol.  II.  James  C.  Southall's  Epoch  of  the 
Mammoth  and  the  Apparition  of  Man  upon  the  Earth,  1878,  Chapters  XXII  and  XXIIl. 

2  Am.  Jour.  Sci.  (3),  Vol.  XXI,  pp.  120-123,  Feb.,  1881;  The  Ice  Age  in  North  America,  1889,  Chap- 
ter XX. 

*  Proc.  A.  A.  A.  S.,  Vol.  XXXV,  for  1886,  p.  222.  "  The  History  of  the  Niagara  River,"  Sixth  An.  Rep. 
of  Commissioners  of  the  State  Reservation  at  Niagara,  for  1889,  iJp.  61-84. 

>•  Am.  Jour.  Sci.  (3),  Vol.  XXXIV,  pp.  404,  405,  Nov.,  1887. 


MEASUEEMENTS  OP  POSTGLACIAL  TIME.  239 

deposition  of  modiiied  di'ift  in  the  Connecticut  Valley  at  Northampton. 
Mass.,  from  which  he  believes  that  not  more  than  ten  thousand  years  have 
elapsed  since  the  Ice  age. 

Making-  such  inquiry  also  concerning  the  glaciation  of  Europe,  we 
find  that  in  Wales  and  in  Yorkshire,  England,  the  amount  of  denxxdation  of 
limestone  rocks  on  which  bowlders  lie  has  been  regarded  by  Mr.  D.  Mack- 
intosh as  pi'oof  that  a  period  of  not  more  than  six  thoxxsand  years  has 
elapsed  siixce  the  bowlders  were  left  in  their  positions.^  The  vex-tical 
extent  of  this  dexiudation,  avei'aging  about  6  inches,  is  nearly  the  same 
with  that  observed  in  the  southwest  part  of  the  Province  of  Quebec  by  Sir 
William  Logan  and  Dr.  Robert  Bell,  where  veins  of  quai'tz  marked  with 
glacial  striffi  stand  oxxt  to  various  heights  not  exceeding  1  foot  above  the 
weathei'ed  sux'face  of  the  inclosing  limestone.^ 

Axiother  indication  that  the  final  melting  of  the  ice-sheet  xxpon  British 
Amei-ica  was  separated  by  oxily  a  very  sho^'t  intei'val,  geologically  speak- 
ing-, from  the  present  time  is  seen  in  the  wonderfxxlly  perfect  pi-esex'vation 
of  the  glacial  striation  axxd  polishing  on  the  sxxrfaces  of  the  more  endui-ing 
rocks.  Of  their  character  in  one  noteworthy  district  Dr.  Bell  writes  as 
follows:  "On  Pox'tland  promontoiy,  oix  the  east  coast  of  Hudson's  Bay,  in 
latitxxde  58°,  and  southward,  the  high,  rocky  hills  are  completely  glaciated 
and  bare.  The  striae  are  as  fresh-looking  as  if  the  ice  had  left  them  only 
yesterday.  When  the  sxxn  bxxrsts  xxpon  these  hills  after  they  have  been 
wet  by  the  rain,  they  glitter  and  shine  like  the  tiixned  roofs  of  the  city  of 
Montx'eal."^  Again,  Professor  Ma,coxxn  Avrites  of  the  red  Laurentiaxx  gneiss 
in  the  vicinity  of  Fort  Chipewyan,  at  the  west  end  of  Lake  Athabasca: 
"The  I'ocks  around  the  foi't  are  all  smoothed  aixd  polished  by  ice  action. 
When  the  suxx  shines  they  glistexx  like  so  much  glass,  and  a  persoxx  walkixxg 
upon  them  is  iix  constant  danger  of  falliixg."*  It  seems  impossible  that 
these  rock  exposures  can  have  so  well  withstood  weathei'ing  in  the  severe 
climate  of  those  xxox-therix  regioxis  longer  than  a  few  thousand  yeax's  at  the 

'Quart.  Jour.  Geol.  Soc,  Vol.  XXXIX,  X883,  iu  Proceedings,  pp.  67-69.     Compare  id.,  Vol.  XLII, 
X886,  pp.  527-539. 

-'  Bulletin,  G.  S.  A.,  Vol.  I,  1889,  p.  306. 

3 Bulletin,  G.  S.  A.,  Vol.  I,  p.  .308. 

^Geol.  Survey  of  Canada,  Report  of  Progress,  1875-76,  p.  90. 


240  THE  GLACIAL  LAKE  AGASSIZ. 

most;  and  they  even  siiggest  that  remnants  of  the  continental  ice-sheet 
may  have  Hngered  there  considerably  later  than  the  time,  computed  to  be 
six  to  eight  thousand  years  ago,  when  its  southern  portion  retreated. 

SHORT    DURATION    OF    LAKE    AGASSIZ, 

The  foregoing  measures  of  time,  surprisingly  short,  whether  we  com- 
pare them  on  the  one  hand  with  the  period  of  authentic  human  history  or 
on  the  other  with  the  long  record  of  geology,  carry  us  back  to  the  date 
when  the  ice-sheet  was  melting  a.way  from  the-  basins  of  the  Upper  Mis- 
sissippi, of  the  Red  River  of  the  North,  and  of  the  Laurentian  lakes.  If 
the  postglacial  epoch  has  been  so  short,  we  must  infer  that  the  final  reces- 
sion of  the  ice  was  very  rapid  and  that  its  ban-ier  between  the  Red  River 
Valley  and  Hudson  Bay  was  soon  melted  away.  Though  Lake  Agassiz 
attained  vast  areal  extent,  its  duration  or  extent  in  time  was  geologically 
brief,  as  is  shown  by  the  small  volume  of  its  beach  deposits  and  lacustrine 
sediments  in  comparison  with  the  Pleistocene  lakes  of  the  Great  Basin 
and  with  the  amount  of  postglacial  erosion  and  deposition  on  the  shores 
of  the  great  lakes  tributary  to  the  St.  Lawrence  and  Nelson  rivers.  The 
geologic  suddenness  of  the  final  melting  of  the  ice-sheet,  proved  by  the 
brevity  of  existence  of  its  attendant  glacial  lakes,  presents  scarcely  less  diffi- 
culty for  explanation  of  its  causes  and  climatic  conditions  than  the  earlier 
changes  from  mild  or  warm  preglacial  conditions. to  prolonged  cold  and  ice 
accumulation. 

Comparison  with  postglacial  lakes. — The  disappearance  of  the  greater 
part  of  the  vast  North  American  ice-sheet  probably  occupied  not  more 
than  two  or  tlii'ee  thousand  years ;  and  half  of  this  time  may  measure  the 
duration  of  Lake  Agassiz,  with  the  formation  of  its  beaches  marking  more 
than  thirty  successive  stages  in  the  concurrent  subsidence  of  its  surface 
and  rise  of  the  earth's  crust.  But  even  these  short  estimates  may  be  too 
long.  The  shores  of  Lake  Michigan,  similar  with  those  of  Lake  Agassiz, 
in  the  drift  of  which  they  are  formed,  in  their  north  and  south  trends,  and  in 
the  adjoining  dejjths  of  water,  have  suffered  an  amount  of  erosion  by  the 
lake  waves  diu-ing  postglacial  time  which  very  far  exceeds  the  total  erosion 
that  was  effected  upon  the  shores  of  Lake  Agassiz  during  all  its  stages,  the 


SHORT  DURATION  OF  LAKE  AGASSIZ.  241 

proportion  between  them  being  surely  not  less  than  ten  to  one ;  and  Lake 
Michigan  has  a  similarly  greater  amount  of  beach  dejjosits,  which  upon 
a  large  area  about  its  south  end  are  raised  by  the  wind  in  conspicuous 
dunes.  This  contrast,  indeed,  suggests  that  the  duration  of  Lake  Agassiz 
and  the  recession  of  the  ice-sheet  from  Lake  Traverse  to  the  lower  part 
of  the  Nelson  River  may  have  been  included  within  less  than  one  thousand 
years. 

Likewise,  as  Mr.  Tyrrell  remarks,  beach  ridges  of  larger  size  tnan 
those  of  Lake  Agassiz,  and  composed  of  coarser  shingle,  occur  on  each  of 
the  three  great  lakes  of  Manitoba,  although  these  lakes  are  far  smaller  than 
their  glacial  predecessor  and  therefore  surely  have  less  powerful  waves. 

Comparison  with  Lakes  Bonneville  and  LaJiontan. — During  the  first  high 
stage  of  Lake  Bonneville,  a  fine,  laminated,  olive-gray  clay,  which  weathers 
to  a  pale-yellow  color,  was  spread  throughout  all  the  lower  parts  of  its 
basin,  ascending  also  in  the  shallower  bays  toward  the  upper  shore-lines. 
In  two  typical  deep  sections  this  member  of  the  lacustrine  sediments  has 
an  exposed  thickness,  respectively,  of  90  and  100  feet,  but  its  base  is  not 
seen.  Again,  during  the  second  rise  of  this  lake  it  deposited  a  similarly 
widespread  stratum  of  light-gray  or  cream-colored  marl  or  calcareous  clay, 
weathering  nearly  white,  and  passing  upward  into  a  fine  sand;  and  typical 
sections  show  that  this  marl  and  associated  sand  range  from  20  to  50  feet 
or  more  in  thickness.  In  like  manner.  Lake  Lahontan  during  its  two  high- 
water  periods  deposited  over  all  its  bed  fine  marly  clays,  which  in  the  earlier 
flood  stage  attained  a  thickness  of  more  than  100  feet,  their  base  not  being 
exposed  by  the  deepest  sections,  and  in  the  later  stage  an  average  of  60  to 
75  feet.  These  thick  sediments  occupying  the  basins  of  the  Pleistocene 
lakes  of  Utah  and  Nevada  indicate,  like  their  great  amount  of  shore  ero- 
sion and  correspondingly  massive  beach  deposits,  that  the  term  of  existence 
of  these  lakes  during  each  of  their  high  stages,  and  especially  the  first,  far 
exceeded  that  of  Lake  Agassiz.  No  such  lacustrine  beds  are  generally 
spi-ead  over  the  basin  of  this  glacial  lake,  which  upon  large  tracts,  even  of 
its  lower  portion,  as  on  and  near  the  Red  River,  near  the  lower  Assiniboine 
between  Poplar  Point  and  Winnipeg,  and  adjacent  to  Lake  Manitoba,  Shoal 
Lake,  and  Lake  Winnipeg,  consists  of  till,  with  frequent  bowlders,  the 
MON  XXV 16 


242  THE  GLACIAL  LAKE  AGASSIZ. 

direct  product  of  the  ice-sheet,  very  shghtly  changed  by  its  deposition  in 
the  lake,  and  not  covered  by  any  aqueous  sediments. 

Only  where  tributaries  entered  this  lake  and  brought,  besides  the  ordi- 
nary alluvium  of  their  erosion,  a  much  larger  volume  of  modified  drift  from 
the  melting  ice-sheet,  were  any  important  lacustrine  sediments  laid  down; 
and  these  appear  in  the  form  of  extensive  deltas  of  gravel  and  sand,  with 
fine  silt  spread  over  adjoining  parts  of  the  lake  bottom.  Other  inflowing 
streams,  though  in  several  instances  important  rivers,  as  the  Red  River 
itself  above  Fergus  Falls,  the  Wild  Rice  River  of  Minnesota,  and  the  Red 
Lake  River,  formed  no  noteworthy  delta  accumulations,  which,  however, 
could  not  have  failed  to  be  conspicuously  developed  if  the  lake  had  long 
remained  at  any  of  the  levels  of  its  many  successive  shore-lines.  The  sedi- 
ments in  Lakes  Bonneville  and  Lahontan  were  evidently  derived  in  large 
part  from  wave  erosion  of  their  shores;  but  in  the  case  of  Lake  Agassiz, 
though  its  shores  are  the  easily  eroded  drift,  no  appreciable  lacustrine  beds 
were  supplied  from  this  source.  The  duration  of  Lake  Agassiz  was  very 
short  in  comparison  with  either  of  the  Pleistocene  humid  epochs  of  the 
Great  Basin  and  Cordilleran  mountain  belt. 

Brevity  of  time  required  for  the  formation  of  terminal  moraines. — The 
shortness  of  the  existence  of  Lake  Agassiz  seems,  at  first  thought,  to  pre- 
sent a  difficulty  in  the  brevity  of  the  time  which  would  be  allowed,  if  the 
glacial  lake  endured  only  a  thousand  years  or  less,  for  the  accumulation  of 
the  moraines  described  in  the  preceding  chapter.  By  the  probable  ratios 
of  time  deduced  from  the  extent  of  the  upper  Herman  beach  and  the 
sequence  of  all  the  lower  and  later  beaches,  we  see  that  the  formation  of 
even  the  great  moraines  of  the  Leaf  Hills  and  of  the  south  side  of  Devils 
Lake  could  have  occupied  only  a  small  fraction  of  the  whole  duration  of 
Lake  Agassiz,  perhaps  not  more  than  fifty  or  even  twenty -five  years  for 
amassing  these  morainic  hills  100  to  350  feet  high  on  a  belt  3  to  5  miles 
wide !  For  the  Dovre,  Fergus  Falls,  Leaf  Hills,  and  Itasca  moraines  were 
apjDarently  formed  before  the  completion  of  the  highest  one  in  the  series  of 
four  principal  beaches  which  unite  in  the  Herman  beach  along"  tlie  southern 
75  miles  of  Lake  Agassiz.  But  this  may  be  easily  accepted  when  we  recall 
the  rapidity  of  motion  of  the  thick  and  wide  glaciers  of  Greenland  and 


EAPID  ACCUMULATION  OF  MORAINES.  243 

Alaska,  30  to  100  feet  per  clay.'  Doubtless  the  continental  ice-sheet  moved 
faster  than  the  glaciers  of  the  Alps,  but  the  waste  from  its  border  by  melt- 
ing must  evidently  have  been  less  than  the  discharge  of  ice  from  these 
Arctic  glaciers  where  they  terminate  in  the  sea  and  are  broken  into  bergs 
and  floated  away. 

The  two  factors  on  which  the  a-ccumulation  of  the  temciinal  moraines 
depends  are  the  rate  of  motion  of  the  ice-sheet  and  the  amount  of  the  en- 
glacial  drift  which  was  thus  brought  forward  to  its  margin.  In  the  region 
of  Lakes  Benton,  Shaokatan,  and  Hendricks,  in  southwestern  Minnesota,  we 
have  evidence  that  the  drift  contained  within  the  ice  amounted  to  a  sheet 
at  least  40  feet  thick. ^  As  great  volume  of  englacial  drift  is  also  indicated 
in  Manitoba  by  the  relation  of  the  Birds  Hill  esker  to  the  adjoining  sheet  of 
till.^  The  inequalities  in  the  aggregate  mass  of  the  drift  fonning  different 
poi"tions  of  the  morainic  belts,  causing  these  to  rise  in  great  prominence 
upon  some  areas,  while  in  other  places  they  are  low  and  scanty,  seem  due 
to  unequal  distribution  of  this  drift  within  the  basal  part  of  the  ice-sheet.^ 
It  was  most  abundant  in  those  portions  where  g'lacial  currents  had  con- 
verged between  the  great  lobes  of  the  ice  border  during  the  time  of  maxi- 
mum area  of  this  ice-sheet,  as  from  the  vicinity  of  Minneapolis  and  Lake 
Minnetonka  northwestward  to  the  Leaf  Hills,  to  Lake  Itasca,  and  to  Birds 
Hill,  and  in  the  country  west  and  northwest  of  Cooperstown,  N.  Dak.,  to 
the  Washington  Lakes,  Devils  Lake,  the  Big  Butte,  Broken  Bone  Lake,  and 
to  Turtle  Mountain.  Upon  these  areas  the  morainic  belts  show  a  close 
relationship,  not  only  by  their  parallelism   and  the    similar  positions  of 

'  Helland,  iu  Quart.  Jour.  Geol.  Soc,  Vol.  XXXIII,  1877,  p.  149.  Nature,  Dec.  29, 1887.  Prestwich's 
Geology,  Vol.  II,  1888,  pp.  530-533.  Prof.  G.  F.  Wriglit,  on  the  Muir  Glacier,  Am.  .Jour.  Sci.  (3),  Vol. 
XXXIII,  pp.  1-18,  Jan.,  1887,  and  Ice  Age  iu  North  America,  Chapter  III.  The  dally  motion  of  the  cen- 
tral portion  of  the  Muir  glacier  in  1886  was  reijorted  by  Professor  Wright,  according  to  a  series  of 
measurements,  to  he  from  40  to  70  feet;  hut  in  1890,  when  the  front  of  this  glacier  had  fallen  hack  a 
hsilf  mile  to  two-thirds  of  a  mile  from  its  place  four  years  earlier,  more  reliable  measurements  of  its 
motion  by  H.  F.  Reid  (National  Geographic  Magazine,  Vol.  IV,  pp.  19-84)  and  H.  P.  Gushing  (Am. 
Geologist,  Vol.  VIII,  pp.  207-230.)  show  a  maximum  of  only  about  7  feet  per  day.  In  1886  the  ice  front 
projected  into  the  Muir  Inlet  as  a  promontory,  but  in  1890  it  was  nearly  straight.  At  each  date  the 
length  of  the  ice  front  was  almost  2  miles  and  its  height  about  250  feetiabove  the  water  of  the  inlet, 
which  is  600  feet  deep.  See  a  discussion  of  ''Recent  changes  in  the  Muir  glacier,"  by  S.  Prentiss 
Baldwin,  Am.  Geologist,  Vol.  XI,  pp.  366-375,  June,  1893. 

^Geology  of  Minnesota.  Ninth  Annual  Report,  for  1880,  pp.  322-326 ;  Final  Report,  Vol.  1, 1884,  pp. 
603,  604. 

^  Chapter  IV,  pp.  183-187. 

■•Bulletiu,  G.  S.  A.,  Vol.  Ill,  1892,  pp.  134-148 ;  id..  Vol.  V,  1894,  pp.  71-86.  Am.  Geologist,  Vol.  VIII, 
pp.  376-385,  Dec,  1891 ;  id..  Vol.  XII,  pp.  36-43,  July,  1893. 


244  THE  GLACIAL  LAKE  AGASSIZ. 

reentrant  angles  of  the  ice  border  through  several  stages  in  its  retreat,  but 
also  by  remarkably  massive  accumulations  of  drift  in  corresponding  por- 
tions of  the  successive  moraines.  If  the  average  amount  of  englacial  diift 
thus  supplied  by  the  ice-sheet  where  its  moraines  are  largest  was  equal  to 
a  thickness  of  40  feet,  or  even  20  or  10  feet,  it  will  be  seen  that  these 
moraines  would  require,  with  a  steep  frontal  gradient  of  the  ice  due  to  the 
marginal  melting  and  a  consequent  rate  of  glacial  motion  probably  several 
times  faster  than  that  of  the  Alpine  glaciers,  only  a  few  decades  of  years 
for  their  formation. 

ALTERlSrATIVE    INTERPRETATIOIirS. 

By  T.  C.  Chamberlln. 

It  would  be  remarkable  indeed  if  in  a  discussion  touching  so  many 
vital  phases  of  glacial  history  there  should  not  arise  some  points  on  which 
coworkers  entertain  different  interpretations,  even  though  their  fundamental 
views  be  in  close  harmony.  In  consideration  of  the  partial  responsibility 
for  this  report  resting  upon  the  writer  of  this  note,  by  reason  of  his  official 
relations  to  the  investigation  upon  which  it  is  based,  Mr.  Upham  has  gener- 
ously urged  that  a  statement  of  such  of  our  differences  of  interpretation  as 
may  be  thought  worthy  of  note  be  inserted  in  the  text.  The  suggestions 
here  offered  in  response  to  this  are  made  with  the  full  recognition  of  the 
fact  that  the  investigator  who  has  made  a  special  study  of  the  region  is  far 
more  likely  to  have  reached  the  correct  interpretation  than  one  less  inti- 
mately familiar  with  all  the  facts.  Nevertheless,  alternative  hypotheses 
may  be  worthy  of  statement. 

Mr.  Upham's  interpretation  of  the  history  of  Lake  Agassiz  is  based 
upon  the  belief  that  all  its  deposits  fall  within  that  epoch  near  the  close  of 
the  Glacial  period  during  which  the  earth's  crust  was  either  stationary  or 
differentially  rising  at  the  north.  In  harmony  with  this  belief,  the  upper- 
most or  Herman  beach  is  thought  to  represent  the  outline  of  the  lake 
during  the  entire  period  occupied  by  the  ice  in  its  retreat  from  the  Dovre 
moraine,  lying  close  north  of  Lake  Traverse,  to  the  line  of  the  Mesabi 
moraine,  which  crosses  northern  Minnesota  and  Manitoba.      This  retreat 


DISCUSSION  BY  PEOFESSOR  CHAMBBRLIN.  245 

of  the  ice  involved,  as  is  fully  stated,  tlie  formation  of  a  series  of  three 
prominent  terminal  moraines,  which  represent  either  halts  or  readvances  of 
the  ice  front.  The  Herman  beach  overrides  these  moraines  as  they  come 
down  into  the  borders  of  the  lake  basin.  This  clearly  indicates  that  the 
completion  of  the  beach  formation  was  subsequent  to  that  of  the  moraines. 
But  Mr.  Upham  thinks  that  the  beach  was  in  process  of  formation  through- 
out the  whole  period  occupied  by  the  successive  formation  of  the  several 
moraines  and  the  intervening  retreats  of  the  ice.  The  descriptions  of  the 
beach,  however,  clearly  indicate  that  it  is  not  very  massive  and  is  unac- 
companied by  any  very  considerable  erosion.  It  furthermoi'e  appears  that 
the  southern  portion  is  not  very  notably  stronger  than  the  northern  portion, 
and  there  is  little  inherent  evidence  that  it  is  notably  older.  The  natural, 
if  not  necessary,  inference  from  these  facts,  under  the  hypothesis  of  Mr. 
Upham,  is  that  the  period  occupied  by  the  retreat  of  the  ice  and  the  forma- 
tion of  the  moraines  was  short,  and  his  inferences  with  reference  to  the 
mode  of  the  formation  of  the  moraines  take  forms  in  harmony  with  this 
conviction.  These  interpretations  embrace  some  of  the  most  radical  phases 
of  glacial  action,  and  hence  the  correctness  of  the  conception  that  the  rather 
slender  Herman  beach  represents  the  whole  time  occupied  by  the  forma- 
tion of  the  several  moraines  and  the  intervening  retreats  of  the  ice  front 
becomes  a  subject  of  the  highest  importance. 

The  present  writer  ventures  to  suggest  that  the  whole  history  of  Lake 
Agassiz  may  not  have  fallen  Avithin  the  period  of  stationary  or  rising  crustal 
movement,  but  that  the  early  part  of  it  may  have  taken  place  during  the 
latter  portion  of  the  period  within  which  the  crust  was  being  depressed. 
There  is  no  difference  of  view  respecting  the  former  higher  elevation  of  the 
crust  and  a  following  depression,  which  was  in  turn  followed  by  an  eleva- 
tion. The  only  question  is  whether  the  history  of  Lake  Agassiz  fell  wholly 
within  the  stationary  and  rising  stages,  or  partly  within  the  falling  stage. 
If  the  early  part  of  the  lake's  history  occurred  while  the  crust  was  sinking, 
the  lake  would  be  constantly  expanding  its  borders,  and  hence  its  beach- 
lines  would  be  progressively  buried  by  the  advancing  waters.  In  this 
way  it  may  be  supposed  that  shore-lines  contemporaneous  with  the  several 
moraines  and  with  the  stages  represented  by  the  inter-morainic  till  sheets 


246  THE  GLACIAL  LAKE  AGASSIZ. 

were  formed,  but  were  obliterated  or  buried  by  the  advancing  waters.  It 
may  be  further  supposed  that  this  advance  continued  until. after  all  the 
adjacent  moraines  in  Minnesota  and  North  Dakota  were  formed,  and  that 
it  reached  its  maximum  some  little  time  later;  and  this  may  perhaps  find 
some  support  in  the  crustal  movements  of  the  Atlantic  border  regions.  In 
this  way  it  is  easy  to  understand  how  the  uppermost  or  Herman  beach 
might  have  essentially  the  same  strength  in  all  parts  of  its  length  of  about 
250  miles  from  south  to  north,  and  might  ride  over  the  several  moraines 
with  seeming  impartiality  and  without  notable  variation  in  character.  This 
hypothesis  also  relieves  the  interpretation  of  the  necessity  of  supposing-  that 
the  retreat  of  the  ice  and  the  formation  of  the  moraines  was  especially 
rapid.  It  has  the  advantage  of  not  being  burdened  with  any  hypothesis 
at  all  regarding  the  rapidity  or  slowness  of  the  formation  of  the  moraines, 
nor  with  any  of  the  hypotheses  necessary  to  account  for  the  extraordinary 
rapidity  of  morainic  formation  and  glacial  retreat  which  are  postulated  in 
the  foregoing  pages. 

Mr.  Upham  urges  against  this  hypothesis  the  formation  of  the  rather 
lai'ge  sand  deltas  around  the  border  of  the  lake,  which  he  thinks  were 
deposited  contemporaneously  with  the  existence  of  the  ice  on  the  adjacent 
land,  for  without  the  presence  of  the  ice  in  some  cases,  he  urges,  the  stream 
which  produced  the  deltas  could  not  have  existed.  It  appears  to  the 
present  writer,  however,  that  these  deltas  would  have  been  formed  in  very 
nearly  the  same  way  under  either  hypothesis.  The  chief  difference  between 
the  two  hypotheses,  so  far  as  deltas  are  concerned,  would  lie  in  a  possible 
slight  variation  in  the  height  of  the  delta  surfaces.  Under  the  hypothesis 
just  suggested,  the  gi-eater  part  of  the  material  of  the  deltas  must  have 
been  deposited  when  the  lake  stood  somewhat  lower  than  its  maximum. 
The  delta  summits  would  not  therefore  originally  have  reached  to  the  full 
height  of  the  uppermost  or  Herman  beach.  However,  as  the  shore  con- 
tinued to  advance,  the  streams  would  have  continued  to  build  up  these 
original  deltas,  and  their  later  deposits,  being  contemporaneous  with  the 
Herman  beach,  would  have  brought  the  deltas  up  to  an  accordant  eleva- 
tion, or  at  least  would  have  tended  to  do  so.  An  exception  to  this  would 
perhaps  be  found  in  the  case  of  deltas  whose  rivers  became  extinct  before 


RATE  OF  GLACIAL  MOTION.  247 

the  lake  reached  its  maximum  height,  accepting  the  evidence  that  there 
was  at  least-  one  such.  In  this  case  the  summit  of  the  delta  would 
doubtless  be  somewhat  lower  than  it  would  have  been  if  its  formation  had 
been  continued  until  the  Herman  beach  was  raised.  But  even  in  this  case 
the  shore  drift  and  the  wind  action  that  followed  would  modify  the  original 
form  and  altitude  of  the  delta,  possibly  to  an  extent  sufficient  to  obscure 
such  limited  differences  as  might  distinguish  the  two  hypotheses.  It  does 
not  seem,  therefore,  to  the  present  writer  that  an  argument  of  a  demonstra- 
tive nature  can  be  based  upon  the  deltas,  because  its  validity  must  rest 
upon  the  rather  elusive  differences  in  the  heights  of  the  deltas,  since  it 
does  not  appear  that  it  can  rest  upon  the  mere  existence  of  the  deltas. 
Indeed,  so  far  as  the  magnitude  of  the  deltas  is  concerned,  that  hypothesis 
which  postulates  the  greater  length  of  time  in  the  formation  of  the  sm- 
rounding  glacial  drift  is  the  more  favorable  to  large  deltas,  especially  to 
large  deltas  of  sand  as  distinguished  from  deltas  of  coarser  material  that 
would  be  the  normal  result  of  exceptionally  rapid  melting. 

The  present  writer  does  not  agree  with  Mr.  Upham  in  regard  to  a  high 
rate  of  glacial  movement,  although  he  formerly  entertained  much  the  same 
view.  A  high  rate  of  motion  enters  into  the  interpretation  of  the  phe- 
nomena under  consideration  as  a  factor  in  the  explanation  of  the  supposed 
rapid  production  of  the  till  under  Mr.  Upham's  interpretation.  If  the 
alternative  interpretation  be  adopted,  it  is  relatively  immaterial  what  rate 
of  motion  prevailed. 

It  is  to  be  observed  that  a  rapid  movement  of  the  ice  is  antagonistic 
to  a  rapid  retrea't,  because  the  two  are  directly  opposed  to  each  other. 
With  given  conditions  of  wastage  the  slower  the  ice  movement  the  more 
rapid  the  retreat.  A  rapid  motion,  however,  would  probably  be  helpful  in 
the  rapid  production  and  transportation  of  glacial  debris,  and  so  it  might 
shorten  the  time  required  to  form  the  till  sheets  and  the  moraines. 

In  respect  to  the  evidence  drawn  from  existing  Alaskan  glaciers  in 
support  of  rapid  motion,  the  present  writer  regards  the  measurement  first 
cited,  assigning  a  rate  of  70  feet  per  day,  as  untrustworthy.  The  later 
measurement,  by  Dr.  Reid,  giving  a  rate  of  7  feet  per  day,  is  believed  to 
be  entitled  to  confidence,  but  even  this  rate  is  a  maximum.     The  average 


248  THE  GLACIAL  LAKE  AGASSIZ. 

of  the  measured  portions  of  the  glacier  is  much  less  than  7  feet  per  day, 
and  certain  mimeasured  lateral  lobes  are  nearly  stagnant.  It  is  further 
to  be  observed  that  the  Muir  glacier  is  a  trunk  stream,  the  jomt  product 
of  the  ice  streams  draining  a  large  area.  Moreover,  these  descend  from 
mountain  heights.  They  are  therefore  radically  different  frqm  ice-sheets 
which  spread  out  in  all  directions  on  plains  or  jjlateaus. 

The  evidence  cited  from  Greenland  is  selective  and  exceptional ;  indeed, 
selective  and  exceptional  evidence  is  about  the  only  class  tliat  can  be  cited 
from  Greenland.  No  average  measurements,  nor  anything  approaching 
to  average  measurements,  have  been  made.  The  high  rates  of  move- 
ment of  the  Jacobshaven  glacier,  as  given  by  Helland,  and  of  the  Great 
Karaiak  glacier,  as  given  by  Drygalski,  and  other  similar  measurements, 
are  not  at  all  questioned,  but  these  are  quite  exceptional,  and  almost  as  far 
as  possible  from  being  representative.  They  exhibit  extraordinary  move- 
ments tln-ough  deep,  constricted  straits,  where  the  ice  is  forced  by  the  vast 
accumulations  of  great  areas  in  the  rear,  and  where  the  warm  season 
appears  to  exert  its  earliest  and  greatest  effects.  The  amounts  of  ice  dis- 
charged in  the  form  of  bergs  from  these  two  glaciers  is  ver}^  much  greater 
than  from  any  other  known  points  on  the  ice  front  of  Greenland.  It  is 
perfectly  obvious  that  the  average  border  of  the  Greenland  ice-sheet  does 
not  move  at  a  rate  even  distantly  approximating  that  of  these  two  straits. 
If  it  did  so,  the  whole  coast  of  Greenland  must  be  overwhelmed  almost 
immediately,  because  the  competency  of  the  summer  heat  of  that  region  to 
hold  back  the  edge  of  the  ice  by  melting-  is  very  slight.  Drygalski  esti- 
mated the  annual  sm-face  melting  at  7  feet.  Even  this  is  much  greater 
than  the  annual  surface  melting  of  the  Inglefield  Gulf  region,  judged  by 
that  of  1894.  While  estimates  are  few,  and  even  these  may  need  much 
qualification,  it  is  nevertheless  certain  that  the  average  movement  of  that 
portion  of  the  border  of  the  Greenland  ice-cap  which  lies  upon  the  land  is 
extremely  small.  Of  that  poition  which  ends  in  the  sea  only  a  small  frac- 
tion has  a  high  rate  of  motion,  as  is  shown  by  the  lack  of  activity  in  the 
discharge  of  icebergs.  When  it  is  considered  that  the  land  border  is  very 
much  greater  than  the  sea  border,  and  that  of  the  sea  border  a  portion  has 


ENGLACIAL  DEIFT.  249 

a  relatively  slow  movement,  it  will  be  evident  that  the  average  rate  of 
movement  for  the  border  of  the  great  ice-sheet  of  Greenland  can  not  be 
high;  and  the  average  rate  of  this  border  is  the  nearest  available  analogue 
to  the  border  movement  of  the  still  more  extended  periphery  of  the  ancient 
American  or  Laurentian  glacier. 

The  present  writer  also  differs  with  Mr.  Upham  in  his  views  respecting 
the  amount  and  distribiition  of  the  englacial  drift.  That  considerable  debris 
is  borne  in  the  basal  portion  of  the  ice  is  not  questioned;  indeed,  the  term 
"englacial  drift"  was  proposed  by  the  present  writer  in  recognition  of  its 
importance.  Our  best  evidence  of  the  amount  and  distribution  of  this  is 
derived  from  the  continental  glacier  of  Greenland.  It  is  there  observed 
that  d(^bris  prevails  in  the  lower  50  or  75  feet  of  the  ice-sheet,  and  occa- 
sionally reaches  up  to  100  feet,  or  perhaps  even  160  feet.  The  amount  of 
this  debris,  if  it  were  let  down  directly  upon  the  glacier's  bottom  by  melting 
in  situ,  without  concentration  by  the  forward  motion  of  the  ice,  would  be 
measured  by  a  very  few  feet,  or  by  a  fraction  of  a  foot.  The  forward 
motion  of  the  ice  concentrates  this  at  its  edge,  so  that  it  may  there  reach, 
theoretically,  any  dimension,  entirely  without  regard  to  its  amount  in  any 
given  vertical  section  of  the  ice.  The  thickness  of  the  deposit  formed  from 
the  englacial  drift  is  quite  as  much  dependent  upon  the, length  of  time  dur- 
ing which  the  edge  of  the  ice  remains  at  one  line  as  upon  the  amount  of 
drift  which  the  ice  may  carry  in  any  given  vertical  section.  No  safe 
inferences  from  the  thickness  of  deposits  of  englacial  drift  can  therefore  be 
drawn  with  reference  to  the  amount  of  englacial  material  present  in  any 
given  portion  of  the  glacier.  If  the  ice  were  absolutely  stagnant  the 
deposit  of  englacial  drift  would  be  precisely  that  which  was  held  in  the  ice 
above  the  point  of  deposit.  If  there  was  any  forward  motion  of  the 
ice  while  it  was  being  melted  away,  there  would  necessarily  be  a  concen- 
tration. If  there  be  1  foot  of  englacial  debris  in  a  given  section,  and  the 
ice  moves  forward  40  feet  while  the  external  heat  causes  a  retreat  of  1  foot, 
the  englacial  deposit  should  be  40  feet  deep.  The  thickness  of  the  englacial 
drift  may  therefore  be  quite  as  much  an  expression  of  prolonged  time  as  of 
a  large  content  of  debris  within  the  ice. 


250  THE  GLACIAL  LAKE  AGASSIZ. 

The  present  writer  differs  with  ]\Ir.  Upham  also  in  his  conception  of  the 
way  in  which  the  englacial  di^ris  becomes  at  length  exposed  and  deposited. 
Instead  of  rising  toward  the  surface  of  the  glacier,  it  is  believed,  on  the 
basis  of  observations  in  Greenland,  to  pursue  a  course  nearly  parallel  with 
the  base,  on  the  whole,  and  to  come  out  at  the  extremity  of  the  glacier. 
To  some  slight  extent  it  may  become  superglacial  bv  ablation,  but  onlv  to 
a  limited  degree.  Consonant  with  this  conception,  it  is  believed  that  eskers 
and  similar  formations  of  gravel  are  essentially  subglacial  or  marginal. 

These  fundamental  con.siderations  add  to  the  difficulty  which  the  pres- 
ent writer  experiences  in  accepting  the  idea  of  the  contemporaneity  of  the 
Herman  beach  with  the  formation  of  so  many  important  moraines  and  of 
such  massive  sheets  of  till,  together  with  so  great  a  retreat  of  the  ice  margin. 
This  difficulty  is  enhanced  by  a  comparison  of  the  uppermost  beach  with 
the  lower  ones,  which  are  correlated  with  much  less  important  glacial  action, 
and  yet  do  not  seem  to  be  correspondingly  inferior  in  magnitude. 

The  difficulty  is  somewhat  relieved  by  the  probability  that  while  the 
lake  was  glacier-bound  on  the  north  the  surface  was  covered  throughout  a 
large  part  of  the  year  with  ice,  and  during  the  rest  by  bergs  and  berg- 
lets,  and  that,  as  a  consequence,  wind  action  was  reduced  to  a  minimum. 
This  may  possibly  be  the  line  of  solution  of  the  problem.  Mr.  Upham, 
however,  finds  but  limited  evidence  of  berg  deposits.  These  need  not  be 
great  if  the  englacial  debris  was  of  small  amount;  but  if  it  was  large  the 
protection  of  the  lake  surface  from  wave  action  by  bei'gs  should  find  expres- 
sion in  very  considerable  berg  deposits. 

A  further  difficulty  is  presented  by  the  slightness  of  the  cutting  down 
of  the  outlet  during  the  period  of  the  Hennan  beach.  If,  however,  the 
alternative  hypothesis  is  adopted,  the  trench  of  40  or  50  feet  existing  in 
the  di'ift  plain  previous  to  the  formation  of  the  Herman  beach  should  per- 
haps be  regarded  as  the  work  of  the  outlet  dui'ing  the  earlier  part  of  the 
glacial  retreat,  instead  of  being  referred  to  preglacial  or  interglacial,  or  at 
least  preretreatal,  times.  The  work  done  by  the  outlet  and  by  the  ice  would 
be  thus  brought  more  nearly  into  harmony. 

In  respect  to  the  lowering  of  the  outlet  of  Lake  Agassiz  b}"  stages, 
instead  of  steady  progress,  which  has  been  previously  discussed,  it  appears 


LOWERING  OF  THE  OUTLET.  251 

to  me  worthy  of  sugg-estion  that  the  rhythmical  action  may  be  due  to  a 
rhythmical  factor  inherent  in  the  mode  of  degradation  of  the  river  valley 
below  the  outlet.  Whenever  the  bed  of  a  river  is  formed  of  material  of 
unequal  resistance,  it  is  scarcely  possible  for  it  to  sink  its  channel  by  a 
uniform  downward  cutting.  If  the  bed  is  formed  of  horizontal  strata,  and 
these  have  different  degrees  of  resistance,  it  is  almost  inevitable  that  the 
stream  shall  develop  an  alternation  of  levels  and  falls,  expressing  them- 
selves by  a  succession  of  slack  water  and  rapids,  as  is  well  known.  Con- 
sidered as  a  mode  of  excavation,  the  process  is  what  miners  would  call 
"stoping."  When  one  of  the  stopes,  in  working  up  the  river,  reaches  any 
reservoir  or  lake  that  may  lie  in  its  course,  it  promptly  lowers  it  to  an 
amount  corresponding  to  the  depth  of  the  stope.  If  the  bed  of  the  river  lies 
upon  drift,  essentially  the  same  mode  is  followed,  but  with  some  variation 
in  detail.  The  resistant  factor  in  this  case  consists  of  transverse  barriers, 
such  as  may  be  formed  by  bowlder  belts,  heavy  masses  of  till,  aggregates 
of  coarse  gravel,  and  similar  inequalities  of  the  deposit.  These  arrest  the 
down-cutting  of  the  stream  for  a  time  and  form  rapids  on  their  lower  sides. 
These  rapids  work  away  at  the  barrier  in  stope  fashion.  Meanwhile  the 
stretch  of  river  above  removes  the  less  resisting  material  of  its  bottom 
down  to  a  gradation  plane  or  to  an  actual  base-level  with  reference  to  the 
barrier.  This  brings  about  essentially  the  same  condition  of  alternating 
slack  water  and  i-apids  that  arises  in  connection  with  horizontal  strata. 
When  the  barrier  is  cut  through,  erosion  works  rapidly  up  stream  through 
the  soft  material,  and  if  a  lake  lies  in  its  course  there  will  follow  a  sudden 
lowering.  It  is  not  in  the  nature  of  the  case  that  a  lake  drained  by  a  long 
river  flowing  over  horizontal  beds  or  over  drift  should  be  lowered  uniformly. 
It  does  not  seem  necessary,  therefore,  to  appeal  to  a  series  of  sudden  accel- 
erations and  halts  in  a  movement  of  the  crust  to  account  for  the  rhythmical 
drainage  of  Lake  Agassiz  and  of  the  many  other  lakes  that  exhibit  like 
phenomena,  unless  there  is  independent  evidence  of  such  movements. 

T.  C.  Chamberlin. 


252  THE  GLACIAL  LAKE  AGASSIZ. 

VOLUME  OF  WATER  RECEIVED  ANT)  DISCHARGED  BY  LAKE  AGASSIZ. 

The  present  yearly  discharge  of  water  by  the  Nelson  River  is  probably 
equal  to  a  depth  of  10  to  15  inches  upon  its  entire  basin,  which  is  approxi- 
mately the  same  area  that  sent  its  di-ainage  into  Lake  Agassiz  and  thi-oug-h 
the  River  Warren  and  the  later  outlets  of  this  lake  to  the  sea.  A  half  or 
larger  part  of  the  yeai-ly  rainfall  and  snowfall  on  this  basin  is  returned  to 
the  air  by  evaporation,  leaving  the  volume  stated  to  be  earned  into  Hudson 
Bay  by  the  river.  Thi'ough  a  few  weeks  in  the  spring  the  rapid  snow 
melting  and  accompanying  rains  raise  all  the  streams  and  lakes  which  are 
the  feeders  of  the  Nelson  to  their  flood  stage;  and,  in  contrast,  many  of  the 
watercom'ses  are  dry  in  summer,  autumn,  and  winter,  and  .the  whole  river 
system  is  reduced  to  a  small  fraction  of  its  previous  maximum. 

But  when  the  ice-sheet  was  being  melted  away  and  Lake  Agassiz 
received  its  drainage,  the  volume  of  water  annually  discharged  from  this 
area  was  far  greater  than  now.  Considering  first  the  rainfall  and  snowfall 
of  that  time,  we  must  doubtless  suppose  that  they  somewhat  exceeded  their 
present  amount,  while  the  evaporation  was  less.  It  may  be  estimated,  there- 
■fore,  that  the  water  thus  received  and  discharged  by  Lake  Agassiz  each 
year  was  equivalent  to  a  uniform  depth  of  20  or  30  inches  over  all  its 
hydrographic  basin. 

A  still  larger  tribute  was  derived  from  the  glacial  melting,  which  in  a 
thousand  years,  more  or  less,  dissolved  from  this  area  the  greater  part  of  an 
ice-sheet  2,000  to  6,000  or  8,000  feet  thick.  The  average  yearly  melting 
would  therefore  be  equivalent  to  an  added  depth  of  3  or  4  feet  of  water,  or 
36  to  48  inches,  making,  with  the  supply  from  precipitation,  approximately 
5  to  7  feet  upon  all  the  basin. 

It  thus  appears  that  the  inflow  and  outflow  of  Lake  Agassiz  were  five 
to  eight  times  more  than  those  of  Lake  Winnipeg.  Instead  of  a  flood  dis- 
charge during  a  few  weeks  in  spring,  the  rapid  ice-melting  undoubtedly 
maintained  continuously  tlu'ough  the  warm  half  of  the  year  a  larger  out- 
flow from  Lake  Agassiz  than  the  spring  stage  of  the  Nelson  River;  but 
during  winters,  when  the  glacial  melting  stopped,  the  discharge  from  the 


FLUVIAL  DEPOSITS,  253 

glacial  lake,  excepting  the  part  due  to  the  capacity  of  the  lake  as  a  reser- 
voir, was  comparatively  small.  In  the  winter  Lake  Agassiz,  becoming  at 
times  mostly  frozen  over,  like  the  present  .great  Laurentian  lakes,  would 
be  drawn  down  to  a  level  several  feet  below  its  summer  height,  and  the 
great  outflowing  river,  as  it  was  during  the  warm  weather,  would  become 
reduced  to  a  stream  resembling  the  lowest  stage  of  the  Nelson. 


FliUVIAIi    DEPOSITS    IN    THE    RED    RIVER    VALIiEY, 

When  the  bed  of  Lake  Agassiz  was  gradually  uncovered  from  the 
water  of  the  receding  lake,  some  parts  of  its  central  plain,  tlrirough  which 
the  Red  River  flows,  probably  remained  as  broad,  shallow  basins  of  water, 
which  that  river  and  its  tributaries  have  since  filled  with  their  fine  clayey 
alluvium.  The  similar  clayey  silt  brought  into  Lake  Agassiz  by  its  delta- 
forming  affluents,  the  Buff'alo,  Sand  Hill,  Sheyenne,  Pembina,  and  Assini- 
boine  rivers,  and  others  farther  north,  had  been  spread  over  large  areas  of 
the  lake-bed,  but  more  extensive  portions  had  a  surface  of  till,  with  no  such 
lacustrine  deposit.  Over  these  formations  much  alluvium  has  been  laid 
down  along  all  the  avenues  of  drainage  of  the  old  lake-bed,  and  it  has 
filled  depressions  of  the  original  surface,  whether  of  lacustrine  sediments 
or  of  till,  being  distinguishable  from  the  former  only  by  its  containing  in 
some  places  shells  like  those  now  living  in  the  shallow  lakes  of  the  country 
adjoining  the  area  of  Lake  Agassiz,  remains  of  rushes  and  sedges  and  peaty 
deposits,  as  of  the  present  marshes  of  the  Red  River  Valley,  and  occasional 
branches  and  logs  of  wood,  such  as  are  floated  down  by  streams  in  their 
stages  of  flood.  Thus  the  occurrence  of  shells,  rushes,  and  sedges  in  these 
alluvial  beds  at  McCauleyville,  Minn.,  32  and  45  feet  below  the  surface,  or 
about  7  and  20  feet  below  the  level  of  the  Red  River,  of  sheets  of  turf, 
many  fragments  of  decaying  wood,  and  a  log  a  foot  in  diameter  at  Glyn- 
don,  Minn.,  13  to  35  feet  below  the  surface,  and  numerous  other  observa- 
tions of  vegetation  elsewhere  along  the  Red  River  Valley  in  these  beds, 
demonstrate  that  Lake  Agassiz  had  been  di-ained  away,  and  that  the  valley 
was  a  land  surface  subject  to  overflow  by  the  river  at  its  stages  of  flood. 


254  THE  GLACIAL  LAKE  AGASSIZ. 

Avlieu  these  remains  were  deposited.^  Even  at  the  present  time  much  of 
the  area  of  stratified  clay  that  ahnost  continuously  forms  the  central  part 
of  the  valley  plain  is  covered  by  the  highest  floods,  and  probably  no  por- 
tion of  it  is  more  than  10  feet  above  the  high- water  line  of  the  Red  River 
and  its  tributaries.  The  position  of  the  thick  beds  of  fine  silt  and  clay  in 
the  central  depression  of  the  Red  River  Valley  shows  that  they  were  not 
mainly  deposited  by  the  waters  of  Lake  Agassiz,  which  must  have  spread 
them  somewhat  equally  over  both  the  lower  and  higher  parts  of  the  lacus- 
trine area,  but  instead  appears  to  prove  that  at  least  their  upper  and  gi-eater 
part  was  brought  by  the  rivers  which  flowed  into  this  hoUow  and  along  it 
northward  after  the  glacial  lake  was  withdrawn. 

ASSOCIATED    GLACIAI.    LAKES. 

The  review  of  the  history  of  Lake  Agassiz  will  be  completed  by  bring- 
ing into  comparison  with  it  the  contemporaneous  formation  of  great  glacial 
lakes  on  the  northern  borders  of  the  United  States  and  the  adjoining  south- 
ern edge  of  Canada,  and  in  its  northwestern  interior,  from  the  city  of  Quebec 
on  the  east  to  the  elbows  of  the  South  and  North  Saskatchewan  rivers  and 
to  the  head  streams  of  the  Mackenzie  on  the  west.  The  glacially  dammed 
Laiu-entian  lakes,  and  a  very  large  extension  of  Lake  Ontario  or  Iroquois, 
and  the  later  glacial  Lake  St.  Lawrence,  east  to  Quebec,  northwest  in  the 
Ottawa  Valley,  and  south  in  the  basin  of  Lake  Champlain  and  the  Hudson 
Valley,  were  quite  probabl}-,  as  before  noticed,  portions  of  the  avenues  of 
outflow  from  Lake  Agassiz  after  it  had  fallen  below  the  Lake  Traverse  out- 
let and  before  Hudson  and  James  bays  were  so  far  uncovered  from  the 
ice-sheet  as  to  be  occupied  by  the  sea  and  receive  the  northeastward  out- 
flow of  the  Winnipeg  and  Saskatchewan  basin.  In  Minnesota  and  South 
and  North  Dakota  prophecies -of  Lake  Agassiz  had  been  given  by  the  earlier 
glacial  lake  of  the  area  now  drained  by  the  Blue  Earth  and  Minnesota 
rivers,  which  may  be  named  Lake  Minnesota,  and  by  a  long  and  narrow 
contemporaneous  lake  in  the  James  River  Valley,  which  Prof.  J.  E.  Todd 

'Geology  of  Minnesota,  Vol.  II,  pp.  529,  530,  663,  664,  668,  and  669.  See  notes  of  wells,  Chapter 
X,  in  McCauleyville,  Wilkin  County;  Glyndon,  Clay  County;  and  Antlover,  Polk  County,  Minn. ;  and 
in  Johnstown,  Grand  Forks  County,  and  near  Grafton,  Walsh  County,  N.  Dak. 


ASSOCIATED  GLACIAL  LAKES.  255 

has  explored  and  named  Lake  Dakota.  Farther  to  the  northwest  the 
glacial  Lakes  Souris  and  Saskatchewan  were  tributary  to  Lake  Agassiz,  and 
had  a  most  interesting  history  in  their  changes  of  outlets  and  relationship 
to  the  Sheyenne,  Pembina,  and  Assiniboine  deltas  of  this  lake.  PI.  Ill,  in 
Chapter  I,  shows  on  a  small  scale  the  position  and  extent  of  the  glacial 
Lakes  Minnesota,  Dakota,  Souris,  and  Saskatchewan,  with  their  relationship 
to  Lake  Agassiz. 

Even  beyond  the  present  continental  watershed  which  divides  the  trib- 
utaries of  Hudson  Bay  from  those  of  the  Arctic  Ocean,  glacial  lakes  cover- 
ing large  areas  now  drained  to  the  Mackenzie  flowed  into  Lake  Agassiz, 
and  portions  of  the  courses  of  their  outlets  have  been  discovered.  The 
recession  of  the  ice-sheet  upon  all  the  country  from  Quebec  to  the  Peace 
River  pent  up  vast  lakes  in  front  of  its  steep  and  high  barrier,  until  the 
present  lines  of  drainage  along  the  slopes  of  the  land  were  opened  and  the 
Glacial  and  Champlain  epochs  were  ended. 

THE    LAURENTIAN   LAKES. 

This  term,  which  is  a  synonym  for  the  five  great  lakes,  Superior, 
Huron,  with  Greorgian  Bay,  Michigan,  Erie,  and  Ontario,  outflowing  by 
the  River  St.  Lawrence,  may  also  include  the  smaller  Lake  Champlain, 
tributary  to  the  St.  Lawrence  by  the  River  Sorel  or  Richelieu.  During 
the  earlier  stages  of  the  glacial  recession  many  small  lakes  were  formed 
along  the  northern  side  of  the  great  watershed  that  separates  the  Missis- 
sippi, Ohio,  Susquehanna,  Delaware,  Hudson,  and  Connecticut  rivers  from 
the  St;  Lawrence,  with  outflows  to  the  south  across  each  principal  depres- 
sion in  the  southern  rim  of  the  St.  Lawrence  basin.  But  at  length,  as  the 
ice  further  retreated,  these  became  merged  into  a  few  large  glacial  lakes, 
the  precursors  of  the  present  great  lakes  of  our  northern  frontier.  Finally 
there  existed  in  succession  two  of  these  bodies  of  water,  each  much  larger 
than  Lake  Superior,  but  smaller  than  Lake  Agassiz,  which  more  especially 
claim  attention.  They  have  been  named  by  Prof.  J.  W.  Spencer  Lake 
Warren  and  Lake  Iroquois.^ 

'  Proc.  A.  A.  A.  S.,  Vol.  XXXVII,  for  1888,  pp.  197-199.  " The  Iroqaois  beach :  a  chapter  in  the  geo- 
logical history  of  Lake  Ontario,"  Trans.  Royal  Society  of  Canatla,  Vol.  VII,  sec.  4, 1889,  pp.  121-134, 
with  map;  and  "The  deformation  of  Iroquois  beach  and  birth  of  Lake  Ontario,"  Am.  Joiir.  Sci.  (3), 
Vol.  XL,  pp.  443-451,  Dec,  1890. 


256  THE  GLACIAL  LAKE  AGASSIZ. 

From  the  western  part  of  the  basin  of  Lake  Superior  a  glacial  lake 
oiitflowed  to  the  Mississippi  at  the  lowest  point  of  the  present  watershed 
between  the  Bois  Brul^  and  St.  Croix  rivers,  in  northwestern  Wisconsin. 
The  bed  of  the  old  outlet  is  1,070  feet  above  the  sea,  or  468  feet  above 
Lake  Superior,  and  it  is  bordered  by  bluffs  of  di-ift  about  75  feet  higli, 
showing  that  when  the  course  of  outflow  began  here  the  West  Superior 
glacial  lake  was  approximately  550  feet  above  the  present  lake  level.  The 
divide  in  this  former  watercourse  is  a  swamp,  extending  several  miles  in 
a  valley  eroded  75  to  100  feet  below  the  adjoining  country,  the  distance 
between  its  bluffs  being  mostly  about  1  mile,  but  in  the  narrowest  place 
only  about  1,000  feet.  The  highest  part  of  the  swamp  at  the  divide  is 
1,070  feet  above  the  sea,  but  it  has  probably  been  filled  20  or  25  feet  since 
the  lake  forsook  this  mouth,  which  was  thus  lowered  by  erosion  to  450  feet, 
approximately,  above  the  present  Lake  Superior.  Springs  in  the  swamp, 
outflowing  partly  to  the  Bois  Bruld  and  partly  to  the  St.  Croix,  are  nearly 
60  feet  above  the  long  and  narrow  Upper  St.  Croix  Lake,  which  is  1,011 
feet  above  the  sea.  This  and  the  similar  but  larger  Lake  St.  Croix  (low 
and  high  water  667  to  687  feet  above  the  sea,  with  maximum  depth  of  25 
feet  at  the  stage  of  low  water),  tlirough  Avhich  the  river  of  this  name  flows 
near  its  mouth,  lie  in  portions  of  the  glacial  river  com'se  which  have  now 
become  dammed  at  the  upper  lake  by  the  gi'avel  and  sand  deposits  of  trib- 
utaries, and  at  the  lower  lake  by  those  of  the  Mississippi,  raising  the  level 
of  the  mouth  of  the  St.  Croix  since  the  departure  of  the  ice  reduced  the 
river  to  its  present  size.^ 

Silts  referable  to  the  Western  Superior  glacial  lake  are  found  near 
Superior  and  Duluth,  and  its  delta  deposits  and  shore-lines  are  traceable 
here  and  there  along  the  northwestern  shore  of  Lake  Superior  in  Minne- 
sota, but  it  may  well  be  doubted  whether  they  extend  into  Canadian  terri- 
tory. Before  the  ice-sheet  had  retreated  so  far  as  to  uncover  the  region 
about  Port  Ai'thur,  its  departure  from  Wisconsin  and  the  greater  part' of 
Micliigan  had  probably  permitted  Lake  Superior  to  become  confluent  with 
Lake  Michigan,  thus  forming  the  glacial  Lake  Wan-en,  with  outlet  by  Chi- 
cago to  the  Des  Plaines,  Illinois,  and  Mississippi  rivers.     Like  the  beaches 

'  Geology  of  Minnesota,  Vol.  II,  pp.  642,  643. 


LAKE  WARREN.  257 

of  Lake  Agassiz,  the  shores  of  the  Western  Superior  lake  and  of  Lake 
Warren  show  tliat  the  departure  of  the  ice  was  attended  by  a  northward 
uplift  of  the  lan-d.^ 

Lake  Warren  was  probably  contemporaneous  with  the  maximum  ex- 
tension of  Lake  Agassiz,  and  it  may  have  continued  until  that  lake  began 
to  outflow  northeastward.  It  belonged  to  stages  in  the  departure  of  the 
ice-sheet  which  appear  to  have  permitted  confluent  sheets  of  water  to 
stretch  as  a  single  lake  from  the  western  end  of  the  basin  of  Lake  Ontario 
over  the  whole  or  the  greater  part  of  the  four  higher  Laurentian  lakes. 
During  the  glacial  retreat  from  Lake  Michigan  and  the  western  portion 
of  Lake  Erie  each  of  these  areas  had  an  outlet  to  the  Mississippi,  that  of 
Lake  Michigan  crossing  the  height  of  land  close  west  of  Chicago,  only  12 
or  15  feet  above  the  lake  and  approximately  595  feet  above  the  sea,  while 
the  outflow  from  Lake  Erie  passed  over  the  lowest  point  of  the  watershed 
between  the  Maumee  and  the  Wabash,  770  feet  above  the  present  sea-level. 
The  departure  of  the  ice  from  the  southern  peninsula  of  Michigan,  how- 
ever, gave  to  the  glacial  Lake  Erie,  with  its  extension  northward  over  Lake 
St.  Clair  and  the  southern  end  of  Lake  Huron,  a  lower  outlet  across  the 
watershed  of  the  Shiawassee  and  Grand  rivers,  allowing  the  Western  Erie 
glacial  lake  to  flow  into  the  glacial  Lake  Michigan  or  Warren  by  a  pass 
whioli  is  now  729  feet  above  the  sea.  Soon  after  this  the  further  recession 
of  the  ice  permitted  Lake  Warren  to  extend  as  one  level  through  connect- 
ing straits  from  Lakes  Ontario  and  Erie  to  Lake  Superior,  discharging  its 
sm-plus  waters  by  the  Chicago  outlet. 

Subsequent  stages  of  the  glacial,  recession,  uncovering  an  outlet  from 
the  Lake  Ontario  basin  by  Rome  to  the  Mohawk  and  Hudson,  and  the 
history  of  the  Niagara  River  and  of  the  glacial  Lake  Ontario  or  Iroquois, 
have  been  ably  discussed  by  Gilbert.^     On  a  difl'erent  theory,  not  recog- 

'The  recent  explorations  of  the  ancient  elevated  shore-lines  about  Lake  Superior  and  the  northern 
parts  of  Lakes  Michigan  and  Huron  by  Dr.  A.  C.  Lawson  and  Mr.  F.  B.  Taylor,  the  earlier  work  by 
Spencer,  Gilbert,  and  others  about  Georgian  Bay  and  Lakes  Erie  and  Ontario,  and  the  history  of  the 
eight  distinct  large  glacial  lakes  which  successively,  and  in  part  contemporaneously,  occupied  the 
basins  of  these  Laurentian  hikes,  are  reviewed  by  the  present  writer,  with  citations  of  the  somewhat 
voluminous  literature  of  this  subject,  in  the  American  Journal  of  Science  (3),  Vol.  XLIX,  pp.  1-18,  with 
map,  Jan.,  1895. 

-"Changes  of  level  of  the  Great  Lakes,'"  in  The  Forum,  Vol.  V,  pp.  417-428,  June,  1888;  and 
"  History  of  the  Niagara  River,"  in  Sistli  Annual  Report  of  the  Commissioners  of  the  State  Reserva- 
tion at  Niagara,  for  1889,  pp.  61-84,  with  three  maps  (also  in  Smithsonian  Annual  Report,  1890). 

MON    XXV 17 


258  THE  GLACIAL  LAKE  AGASSIZ. 

uiziug  au  ice-shee-t  and  referring  the  high  ancient  beaches  of  this  basin  to 
marine  submergence,  the  same  field  has  also  been  elaborately  studied  by 
SjDencer.-'  According  to  the  glacial  theory  held  by  Gilbert,  which  seems  to 
me  the  true  one,  while  the  retiring  ice-sheet  still  rested  against  the  Adiron- 
dack Mountains,  and  thence  stretched  across  the  St.  Lawrence  Valley  to 
the  Laurentide  highlands  north  of  Montreal  and  Quebec,  the  glacial  Lake 
Iroquois,  outflowing  at  Rome,  formed  a  well-marked  beach  which  Gilbert 
has  mapped,  with  determinations  of  its  height  by  leveling,  from  the  Niagara 
River  east  to  Rome  and  north  to  the  vicinity  of  Watertown.  The  Canadian 
portion  of  this  beach,  surrounding  the  western  end  of  Lake  Ontario  and 
running  along  its  northern  side  to  the  vicinity  of  Belleville,  has  been  simi- 
larly traced  by  Spencer.  The  height  of  Lake  Ontario  is  247  feet,  and  that 
of  the  old  outlet  crossing  the  watershed  at  Rome  is  440  feet  above  the  sea- 
level.  Thence  the  highest  Iroquois  beach,  in  its  course  adjacent  to  the 
eastern  end  of  Lake  Ontario,  has  a  gradual  ascent  of  about  5  feet  per  mile 
along  a  distance  of  55  miles  northward  to  the  latitude  of  Watertown,  where 
the  highest  beach  is  730  feet  above  the  sea,  showing  that  a  differential  uplift 
of  about  290  feet  has  taken  place,  in  comparison  with  the  Rome  outlet. 
From  Rome  westward  to  Rochester  the  beach  has  nearly  the  same  height 
with  the  outlet,  but  farther  westward  it  descends  to  385  feet  above  the  sea 
at  Lewiston  and  363  feet  at  Hamilton,  at  the  western  end  of  Lake  Ontario. 
Continuing  along  the  beach  north  of  the  lake,  the  same  elevation  with  the 
Rome  outlet  is  reached  near  Toronto,  and  thence  east-northeastward  an 
uplift  is  found,  similar  to  that  before  noted  east  of  the  lake,  its  amount 
near  Trenton  and  Belleville,  above  Rome,  being  about  240  feet. 

Only  two  surfaces  of  former  levels,  which  are  supplied  by  the  old 
shores  of  Lakes  Warren  and  Iroquois,  conduct  us  from  Chicago  to  Water- 
town  and  the  mouth  of  Lake  Ontario.  Between  the  level  of  Lake  Warren, 
at  the  eastern  end  of  Lake  Erie,  and  the  latest  level  and  highest  beach  of 
Lake  Iroquois,  at  the  western  end  of  Lake  Ontario,  while  it  outflowed  at 
Rome,  there  is  a  vertical  fall  of  approximately  500  feet;  and  from  the  latest 
in  the  series  of  several   Iroquois   beaches  near  Watertown,   where  they 

'Papers  liefore  cited;  also  Am.  Jour.  Sci.  (3),  Vol.  XLI,  pp.  12-21  and  201-211,  with  maps,  Jan.  and 
March,  1891. 


LAKE  IROQUOIS.  259 

occupy  a  vertical  range  of  about  80  feet,  the  lowest  being  the  last  formed, 
corresponding  to  the  highest  beach  at  Hamilton,  there  is  a  fall  of  about 
400  feet  to  the  St.  Lawrence  at  its  outflow  from  Lake  Ontario  through  the 
Thousand  Islands.  These  two  levels,  and  the  respective  descents  of  500 
and  400  feet,  bring  us  to  the  sea-level  of  the  Champlain  epoch,  or  time  of 
departure  of  the  ice-sheet  of  the  Glacial  period,  which  was  the  barrier  of 
these  glacial  lakes;  for  fossiliferous  marine  beds  overlying  the  till  extend 
inland  along  the  St.  Lawrence  Valley  to  Ogdensburg  and  Brockville,  close 
below  the  Thousand  Islands  and  at  the  same  level,  within  a  few  feet,  as 
Lake  Ontario.  From  Lake  Warren  to  the  Champlain  ocean  we  thus  have 
an  apparent  descent  of  900  feet.  But  the  first  and  third  of  the  levels 
which  are  thus  brought  into  close  geographic  correlation,  namely.  Lake 
Warren,  Lake  Iroquois,  and  the  sea,  are  separated  chronologically  by  the 
time  of  existence  of  the  intermediate  Lake  Iroquois,  and  we  must  seek  to 
eliminate  the  changes  of  levels  which  occurred  within  that  time. 

If  the  earliest  beach  of  Lake  Iroquois  had  been  taken  for  this  com- 
parison, there  would  have  been  probably  about  150  feet  more  of  fall  from 
the  level  of  Lake  Warren  at  the  western  end  of  Lake  Ontario,  and  80  feet 
more  of  fall  from  Lake  Iroquois  to  the  sea.  The  230  feet  thus  found  meas- 
ures the  differential  rise  of  the  area  of  Lake  Ontario  during  the  early  part 
of  the  time  between  the  dates  of  Lake  Wan-en  and  of  the  sea  at  Ogdens- 
burg. But  this  differential  uplifting  meanwhile  affected  the  whole  lake 
region,  extending  westward  over  the  area  that  had  been  occupied  by  the 
glacial  Lake  Warren;  and  it  is  probable,  as  shown  by  the  beaches  of  Lake 
Agassiz,  ithat  the  greater  part — indeed,  nearly  all — of  the  265  feet  of 
gradual  change  in  levels  between  Chicago  and  the  eastern  end  of  Lake 
Erie  took  place  during  the  time  of  the  glacial  Lake  Iroquois  and  previous 
to  the  time  of  the  sea-level  in  the  St.  Lawrence  Valley,  with  which  Chicago 
and  Lake  Warren  are  compared.  There  was  also  a  small  amount  of  differ- 
ential rise  of  the  Ontario  basin  during  the  latter  part  of  the  time  of  the 
glacial  recession,  between  the  formation  of  its  latest  beach  with  outflow  by 
Rome  to  the  Mohawk  and  the  complete  departm'e  of  the  ice,  or  more  prob- 
ably the  melting  of  an  avenue  tlu'ough  the  ice-sheet,  on  the  area  crossed 
by  the  St.  Lawrence,  to  which  the  ocean  was  then  extended.     To  carry 


260  THE  GLACIAL  LAKE  AGASSIZ. 

back  our  comparison  of  Chicago  and  Lake  Warren  with  the  sea-level  to 
the  stage  of  the  glacial  recession  when  the  Niagara  and  the  Mohawk  were 
&st  uncovered  from  the  ice,  we  have  then  to  subtract  from  the  900  feet  of 
apparent  descent  an  undetermined  amount,  which  probably  exceeds  230 
feet,  and  very  likely  may  be  .fully  300  feet.  The  height  of  the  Chicago 
outlet  above  the  sea-level  at  the  time  of  greatest  extension  of  Lake  Warren 
is  thus  found  to  have  been  about  650  or  600  feet,  which  differs  only  slightly 
from  its  present  height  of  595  feet.  Chicago  having  had  nearly  the  same 
elevation  as  now,  we  learn  from  the  shore-lines  of  Lake  Warren  that  the 
country  adjoining  the  eastern  end  of  Lake  Erie  was  at  that  time  depressed 
more  than  200  feet,  while  the  region  north  of  Lake  Superior  was  about  500 
feet  lower  than  now.  The  Rome  outlet  of  Lake  Iroquois  was  at  first  50  or 
100  feet  above  the  sea-level,  and  it  was  uplifted  to  about  300  feet  above 
the  sea  while  it  continued  to  be  the  outlet,  and  to  probably  350  feet,  lack- 
ing less  than  100  feet  of  its  present  height,  by  the  time  of  the  extension  of 
the  sea  to  Ogdensburg  and  Brockville. 

Before  proceeding  to  consider  the  later  great  extension  of  Lake  Iro- 
quois we  may  glance  rapidly  over  some  of  the  explanations  of  the  ancient 
elevated  shore-lines  of  the  Laurentian  lakes  which  have  been  offered  by 
successive  writers.  Mr.  Thomas  Roy,  a  civil  engineer  of  Toronto,  in  a 
paper  communicated  in  1837  by  Lyell  to  the  Geological  Society  of  Lon- 
don, regarded  the  body  of  water  that  formed  the  terraces  and  beach  ridges 
near  Toronto  as  an  immense  lake,  with  surface  at  one  time  about  1,000  feet 
above  the  sea,  held  in  on  all  sides  by  formerly  higher  barriers  of  land.^  But 
Lyell  during  his  travels  in  this  country  in  1841-42  examined  these  shore- 
lines with  Mr.  Roy  and  pronounced  them  to  be  of  marine  origin.^  In  1861 
Prof  E.  J.  Chapman  attributed  the  deposition  of  drift  in  this  lake  region  to 
a  marine  submergence  exceeding  1,500  feet;  but  he,  like  all  subsequent 
observers,  was  unable  to  find  any  marine  fossils.  The  beach  ridges  he 
referred  to  a  very  extensive  fresh-water  lake  formed  in  a  later  epoch  when 
the  land  was  uplifted,  the  lake  being  supposed  to  be  held  in  by  a  greater 
elevation  of  the  country  between  the  Adirondacks  and  the  Laurentide  high- 

' Proceedings  Geol.  Soc.  London,  Vol.  II,  pp.  537,  538. 
^Travels  in  North  America,  Vol.  II,  Chapter  XX. 


THEORIES  OF  EOY,  LYELL,  AND  OTHERS.         261 

lands.^  During-  the  same  year  Mr.  Sandford  Fleming  published  a  detailed 
description  and  map  of  the  Davenport  ridge  and  ten-ace,  which  are  portions 
of  the  highest  Iroquois  shore-line  near  Toronto,  referring  them  to  the 
action  of  Lake  Ontario  when  it  stood  "about  170  feet  above  its  present 
level."  ^  The  Gleological  Survey  of  Canada,  in  its  valuable  Report  of  Prog- 
ress to  1863,  described  these  "ancient  beaches,  terraces,  and  ridges"  on 
pages  910  to  915,  but  presented  no  theory  of  their  origin.  In  1877  Mr. 
George  J.  Hinde,  in  a  paper  on  the  glacial  and  interglacial  strata  of  Scar- 
boro  Heights  and  other  localities  near  Toronto,  accounted  for  the  drift  by 
the  agency  of  ice-sheets  during  two  great  epochs  of  glaciation,  separated 
by  a  long-  interglacial  epoch  which  had  a  climate  nearly  like  that  of  the 
present  time.  The  Laurentian  lakes,  at  the  close  of  the  Glacial  period, 
according  to  this  author,  were  much  larger  than  now,  as  shown  by  the  old 
shore-lines;  but  he  is  not  sure  whether  their  barrier  was  the  receding  ice- 
sheet  or  "accumulations  of  glacial  debris  which  have  since  been  removed."^ 
The  southern  high  shore-lines  of  these  lakes,  in  the  United  States,  have 
been  regarded  by  Whittlesey,  Newberry,  Claypole,  and  Gilbert,  as  of  fresh- 
water formation,  the  lakes  having  been  held  higher  than  now  by  the  ice- 
sheet  during-  its  departure;  and  Spencer  and  Taylor  are  the  only  recent 
writers  who  have  examined  this  region  and  believe  the  beaches  to  be  sea 
shores.* 

None  of  these  writers  has  studied  the  question,  Wliere  was  the  ice- 
sheet  latest  a  barrier  across  the  St.  Lawrence  Valley?  The  directions  of 
glacial  strise  and  transportation  of  di'ift  answer  that  the  ice-sheet  in  tliis 
region  during  the  closing  stage  of  glaciation  was  thickest  upon  a  belt 
crossing  the  St.  Lawrence  nearly  from  east-southeast  to  west-northwest  in 

'  Canadian  Joarnal,  new  series,  Vol.  VI,  pp.  221-229  and  497, 498. 

2  Ibid.,  Vol.  VI,  pp.  247-253. 

=  Canadian  Journal,  new  series,  Vol.  XV,  pp.  388-413. 

■•C.  Whittlesey,  "On  the  fresh-water  glacial  drift  of  the  Northwestern  States,"  1864,  pp.  17-22,  in 
Smithsonian  Contributions,  Vol.  XV.  J.  S.  Newberry,  in  Report  of  the  Geological  Survey  of  Ohio,  Vol. 
II,  1874,  pp.  50-65,  with  three  maps.  E.  W.  Claypole,  "The  lake  age  in  Ohio,"  pp.  42,  with  foui'  mai)s, 
in  Trans.  Geol.  Soe.  Edinburgh.  1887.     G.  K.  Gilbert  and  J.  W.  Spencer,  papers  before  cited. 

Since  this  page  was  first  written,  Mr.  F.  B.  Taylor  has  claimed  a  marine  origin  for  some  of  the 
ancient  beaches  about  portions  of  these  lakes,  and  for  deltas  in  the  Mohawk  Valley  ("The  highest  old 
shore-line  on  Mackinac  Island,"  Am.  Jour.  Sci.  (3),  Vol.  XLIII,  pp.  210-218,  March,  1892;  "The  deltas 
of  the  Mohawk,"  Am.  Geologist,  Vol.  IX,  pp.  344, 345,  May,  1892;  and  later  papers  in  the  Am.  Geologist, 
Vols.  XIII-XV,  1894-95). 


262  THE  GLACIAL  LAKE  AGASSIZ. 

the  vicinity  of  Quebec.  Thence  its  currents  pushed  up  the  valley  by  Mon- 
treal, and  also  down  the  valley,  filling  the  broad  estuary  of  the  river  to  the 
gulf;  and  on  that  tract,  at  or  below  Quebec,  doubtless  the  last  remnant  of 
the  ice  barrier  was  melted  away,  allowing  the  sea  ingress  westward  to  Lake 
Champlain,  to  the  mouth  of  Lake  Ontario,  and  to  Allumette  Island,  in  the 
Ottawa.  Previous  to  this,  while  an  arm  of  the  sea  had  been  washing 
the  ice  border  and  thus  increasing  its  speed  of  retreat  in  the  Gulf  of  St-. 
Lawrence  and  west  toward  Quebec,  the  g-lacial  lake's  waves  on  the  other 
side  of  the  narrowing  ice  belt  in  this  valley  had  likewise  hastened  its 
departure.  Gradually  this  lake,  which  I  have  named  Lake  St.  Lawrence, i 
had  extended  beyond  the  basin  of  Lake  Ontario  to  fill  at  length  the  lower 
part  of  the  Ottawa  basin,  probably  to  the  mouth  of  the  Mattawa,  and  it  had 
spread  eastward  around  the  northern  side  of  the  Adirondacks  to  Lake 
Champlain  and  Montreal,  and  down  the  St.  Lawrence  Valley  probably  to 
Quebec  or  farther,  when  the  ice  dam  between  it  and  the  sea  disappeared. 
The  glacial  Lake  St.  Lawrence,  until  this  time  outflowing  to  the  ocean  by 
the  Hudson  River,  then  ceased  to  exist;  Lake  Ontario  became  a  separate 
sheet  of  fresh  water;  and  the  sea,  at  a  somewhat  lower  level  than  Lake  St. 
Lawrence  had  held,  stretched  to  the  Thousand  Islands,  where  the  St.  Law- 
rence River,  at  first  only  a  few  miles  long  and  with  scarcely  perceptible 
fall,  discharged  the  outflow  of  Lake  Ontario  into  the  prolonged  Gulf  of 
St.  Lawrence. 

Another  branch  of  this  theme  needs  to  be  added,  telling  the  history  of 
the  continuous  Hudson  and  Lake  Champlain  Valley  during  the  recession 
of  the  ice-sheet,  up  to  the  time  of  this  opening  of  its  northern  portion  to  the 
ocean.  The  absence  of  marine  fossils  in  beds  overlying  the  glacial  drift 
on  the  shores  of  southern  New  England,  Long  Island,  and  New  Jersey, 
and  the  watercourses  which  extend  from  the  terminal  moraine  on  Long 
Island  southward  across  the  adjacent  modified  diift  plain  and  continue 
beneath  the  sea-level  of  the  Great  South  Bay  and  other  bays  between  the 
shore  and  its  bordering  long  beaches,  prove  that  this  coast  stood  higher 
than  now  when  the  ice-sheet  here  extended  to  its  farthest  limit.  A 
measure  of  this  elevation  of  the  seaboard  in  the  vicinity  of  New  York 

'  Am.  Jour.  Sci.  (3),  Vol.  XLIX,  pp.  1-18,  with  map,  .Tan.,  1895. 


LAKE  HUDSON-CHAMPLAIN.  263 

during  the  Late  Glacial  or  Champlain  epoch  is  supplied,  as  I  believe,  by 
the  shallow  submarine  channel  of  the  Hudson,  which  has  been  traced  by 
the  soundings  of  the  United  States  Coast  Survey  from  about  12  miles  off 
Sandy  Hook  to  a  distance  of  about  90  miles  southeast  from  the  Hook.^  This 
submerged  channel,  lying  between  the  present  mouth  of  the  Hudson  and 
the  very  deep  submarine  fjord  of  this  river,  ranges  from  10  to  15  fathoms 
in  depth,  with  an  average  width  of  IJ  miles,  along  its  extent  of  80  miles, 
the  depth  being  measured  from  the  top  of  its  banks,  which,  with  the  adja- 
cent sea-bed,  are  covered  by  15  to  40  fathoms  of  water,  increasing  south- 
eastward with  the  slope  of  this  margin  of  the  continental  plateau. 

During  the  whole  or  a  considerable  part  of  the  time  of  the  glacial 
Lakes  L-oquois  and  St,  Lawrence,  this  area,  stretching  100  miles  south- 
eastward from  New  York,  was  ^jrobably  a  land  surface  across  which  the 
Hudson  flowed  with  a  slight  descent  to  the  sea.  But  northward  from 
the  present  mouth  of  the  Hudson  the  land  stood  lower  than  now,  and  the 
amount  of  its  depression,  beginning  near  the  city  of  New  York  and 
increasing  from  south  to  north,  as  shown  by  ten-aces  and  deltas  of  the 
glacial  Lake  Hudson-Champlain,  which  were  formed  before  this  lake 
became  merged  with  Lake  Iroquois,  was  nearly  180  feet  at  West  Point, 
275  feet  at  Catskill,  and  340  feet  at  Albany  and  Schenectady."  Farther  to 
the  north,  according  to  measurements  by  Baron  de  Geer  of  the  altitudes 
of  the  highest  shore  marks  in  the  part  of  the  St.  Lawrence  basin  which 
was  filled  l^y  the  glacial  Lake  St.  Lawrence,  formed  by  the  union  of  the 
two  preceding,  the  depression  was  nearly  657  feet  at-  St.  Albans,  Vt;  640 
feet  on  the  north  side  of  the  Adirondacks,  southeast  of  Moira,  N.  Y.; 
625  feet  on  Mount  Royal,  at  Montreal;  and  718  feet  on  the  hills  a  few 
miles  north  of  the  city  of  Ottawa.^  From  these  figures,  however,  both 
in  the  Hudson  aul  St.  Lawrence  basins,  we  must  subtract  the  amount  of 
descent  of  the  Hudson  River,  which  in  its   channel  outside  the  present 

'A.  Lindenkohl,  Am.  Jour.  Soi.  (3),  Vol.  XXIX,  pp.  475-480,  June,  1885,  and  Vol.  XLI,  pp.  489-499, 
June,  1891.  J.  D.  Dana,  Am.  Jour.  Sci.  (3),  Vol.  XL,  pp.  425-437,  Dec,  1890,  -witli  map  reduced  from  a 
chart  of  the  U.  S.  Coast  Survey. 

2  J.  S.  Newberry,  Popular  Science  Monthly,  Vol.  XIII,  pp.  641-660,  Oct.,  1878.  F.  J.  H.  Merrill, 
Am.  Jour.  Sci.  (3),  Vol.  XLI,  pp.  460^66,  June,  1891.  W.  M.  Davis,  Proceedings,  Boston  Society  of 
Natural  History,  Vol.  XXV,  pp.  318-335,  1891.  Warren  Upham,  Bulletin,  G.  S.  A.,  Vol.  I,  1890,  p.  566; 
Vol.  II,  1891,  p.  265. 

'Proceedings,  Boston  Society  of  Natural  History,  Vol.  XXV,  1802,  pp.  454-477,  with  map. 


264  THE  GLACIAL  LAKE  AGASSIZ. 

harbor  of  New  York  may  probably  have  been  once  50  or  60  feet  in  its 
length  of  about  100  miles.  Before  the  time  of  disappearance  of  the  ice- 
barrier  at  Quebec  this  descent  may  have  been  diminished,  or  the  seaboard 
at  New  York  may  have  sunk  so  as  to  bring  the  shore-line  nearly  to  its 
present  position ;  but  the  Hudson  Valley  meanwhile  had  been  uplifted,  so 
that  an  outflow  from  Lake  St.  Lawrence  crossed  the  low  divide,  now  about 
150  feet  above  the  sea,  between  Lake  Champlain  and  the  Hudson.  This 
is  known  by  the  extension  of  fossiliferous  marine  deposits  along  the  Lake 
Champlain  basin  nearly  to  its  southern  end,  while  they  are  wholly  wanting 
along  all  the  Hudson  Valley.  Indeed,  the  outflowing  river  from  Lake  St. 
Lawrence  or  the  Hudson  during  the  subsequent  postglacial  epoch  chan- 
neled the  lower  part  of  this  valley  to  a  depth  of  about  100  feet  below  the 
present  sea-level,  proving  that  the  land  there,  as  Merrill  points  out,  stood 
so  much  higher  than  now  during  some  time  after  the  ice  retreated. 

When  Lake  Iroquois  ceased  to  outflow  at  Rome,  and  after  intervening 
stages  of  outlets  existing  for  a  shoi't  time  at  successively  lower  levels  north 
of  the  Adirondacks  began  to  occupy  the  Lake  Champlain  basin,  outflowing 
thence  to  the  Hudson,  its  surface  fell  by  these  stages  about  250  feet  to  the 
glacial  Lake  Hudson-Champlain,  which  had  doubtless  reached  northward 
along  the  whole  length  of  the  Champlain  basin.  The  level  of  the  resulting 
Lake  St.  Lawrence  at  the  later  time  of  ingress  of  the  sea  past  Quebec  fell 
probably  50  feet  or  less  to  the  sea-level.  During  these  changes  the  out- 
flow of  Lake  Agassiz  may  have  passed  in  the  ways  before  described  to 
the  sea  through  the  Hudson,  and  afterward  to  the  enlarged  Gulf  of  St. 
Lawrence,  if  the  sea  had  not  previously  come  into  Hudson  Bay. 

LAKE    MINNESOTA. 

Before  Lake  Agassiz  commenced  to  exist,  the  receding  Minnesota  and 
Dakota  lobes  of  the  ice-sheet  had  each  given  place  to  a  large  lake  on  the 
central  part  of  the  area  from  which  they  withdrew.  By  the  bamer  of 
the  Minnesota  ice-lobe  a  lake  having  an  elevation  of  about  1,150  feet 
above  the  sea  was  formed  in  southern  Minnesota,  in  the  basin  of  the 
Blue  Earth  and  Minnesota  rivers,  outflowing  southward  by  way  of  Union 
Slough  to  the  East  Fork  of  the  Des  Moines.  In  its  maximum  extent  this 
lake  probably  had  a  length  of  160  miles,  from  AVaseca  to  Big  Stone  Lake, 


LAKE  MINNESOTA.  265 

with  a  width  of  40  miles  in  Blue  Earth  and  Faribault  counties,  attaining- 
an  area  of  more  than  3,000  square  miles.  The  continued  glacial  recession 
afterward  opened  lower  outlets  eastward  to  the  Cannon  River,  and  at  the 
time  of  the  Waconia  moraine  had  uncovered  the  lower  part  of  the  Minne- 
sota Valley,  permitting  the  lake  to  be  wholly  drained  northeastward  to  the 
Mississij^pi.  ^  Its  existence  was  thus  ended  previous  to  the  beginning  of 
Lake  Agassiz,  which  dates  from  the  next  ensuing  Dovre  moraine. 

The  modified  drift  from  the  retreating  ice  on  the  upper  Minnesota  basin 
was  deposited  along  the  lower  half  of  this  valley,  filling  it  with  stratified 
graved,  sand,  and  clay  to  a  depth  75  to  150  feet  above  the  present  river 
from  New  Ulm  to  its  mouth,  which  shows  that  at  least  this  portion  of  the 
valley  had  nearly  its  present  form  at  the  time  of  final  recession  of  the  ice- 
sheet.  It  seems  also  probable  that  the  upper  part  of  the  channel  above 
New  Ulm,  occupied  by  the  River  Warren  at  the  time  of  the  Herman 
beaches,  was  already  a  distinctly  marked  topographic  feature  when  the 
ice  retreated,  so  that  the  first  outflow  from  Lake  Agassiz  took  its  course 
at  a  level  some  50  feet  below  the  general  surface  adjoining  Lakes  Traverse 
and  Big  Stone  and  Browns  Valley.^  As  long  as  streams  poured  into  this 
valley  directly  from  the  melting  ice-sheet,  its  modified  drift,  gathered  from 
the  ice  in  which  it  had  beeu  held,  continued  to  increase  in  depth;  but 
when  the  ice  had  retreated  beyond  the  limits  of  the  Minnesota  basin,  the 
water  discharged  here  from  Lake  Agassiz  brought  no  modified  drift,  and  was 
consequently  a  most  powerful  eroding  agent.  By  this  River  Warren  the 
valley  drift,  so  recently  deposited,  was  mostly  swept  away,  and  the  channel 
was  excavated  to  a  depth  much  lower  than  the  present  river.  But  since 
Lake  Agassiz  began  to  outflow  northeastward,  the  Minnesota  Valley  and 
that  of  the  Mississippi  below,  carrying  only  a  small  fraction  of  their  former 
volume  of  water,  have  become  considerabl}^  filled  by  alluvial  gi-avel,  sand, 
clay,  and  silt,  which  have  been  brought  in  by  tributaries,  being  spread  for 
the  most  part  somewhat  evenly  along  these  valleys  by  their  floods.^ 

'Geology  of  Minnesota,  Vol.  I,  pp.  460,622,642. 

'Compare  with  Geology  of  Minnesota,  Vol.  I,  pp.  479-485,  rlescribing  the  chains  of  lakes  in 
Martin  County,  Minn.,  which  are  apparently  due  to  preglacial  or  interglacial  watercourses  that  were 
not  wholly  filled  with  drift.  Several  such  chains  of  lakes  are  also  found  in  the  vicinity  of  Eokelson, 
N.  Dak.  (Chapter  IV,  p.  144). 

3"The  Minnesota  Valley  in  the  Ice  age,"  Proc.  A.  A.  A.S.,  Vol.  XXXII,  for  1883,  pp.  213-231;  also 
in  Am.  Jour.  Sei.  (3),  Vol.  XXVII,  Jan.  and  Feb.,  1884. 


266  THE  GLACIAL  LAKE  AGASSIZ. 

LAKE    DAKOTA. 

Prof.  J.  E.  Todd  supplies  me  the  approximate  outline  of  a  lake  named 
by  him  Lake  Dakota,  which  occupied  the  valley  of  the  James  or  Dakota 
River  contemporaneously  with  the  foregoing,  reaching  from  Mitchell  170 
miles  north  to  Oakes  and  varying  from  10  to  30  miles  in  width.^  It  out- 
flowed southward  by  the  present  course  of  the  James  to  the  Missoui'i.  The 
Dakota  ice-lobe,  which  had  filled  this  valley  and  in  its  recession  formed  the 
northern  shore  of  Lake  Dakota,  was  not  therefore  the  cause  of  this  lake  in 
the  same  way  that  the  'lake  in  the  Blue  Earth  and  ]\Iinnesota  basin  and 
Lake  Agassiz  owed  their  existence  to  the  barrier  of  the  ice-sheet  in  its 
retreat.  The  bed  of  Lake  Dakota  has  a  nearly  uniform  elevation  of  1,300 
feet,  or  is  within  10  feet  below  or  above  this,  throughout  its  length;  and 
during  the  glacial  recession  it  was  covered  by  a  lake  whose  shores  have 
now  a  height  of  about  1,300  to  1,350  feet,  probably  ascending  slightly  from 
south  to  north  as  compared  with  the  present  sea-level.  Professor  Todd 
states  that  the  surface  of  this  lacustrine  area  in  its  southern  part,  from 
Mitchell  to  Redfield,  is  nearly  flat  till,  but  thence  northward  is  sand  and 
loess-like  silt,  while  considerable  tracts  of  the  eastern  border  of  its  north 
part  consist  of  low  dunes. 

The  outflowing  James  River  was  cutting  down  its  channel  during  the 
retreat  of  the  ice-lobe,  and  its  erosion  was  so  rapid  as  to  prevent  the  north- 
ern part  of  Lake  Dakota  from  retaining  suflicient  depth  to  outflow  eastward 
into  the  south  end  of  Lake  Agassiz  when  the  way  was  opened  by  the  far- 
ther departure  of  the  ice,  receding  from  the  Head  of  the  Coteau  des  Prai- 
ries and  beginning  to  uncover  the  Red  River  Valley.  A  large  tract  of  the 
sand  and  silt  beds  of  Lake  Dakota,  and  of  a  contiguous  glacial  lake  formed 
in  Sargent  County,  N.  Dak.,  at  the  time  of  the  Dovre  moraine  (p.  148), 
now  sends  its  drainage  to  the  Red  River  by  the  head  stream  of  the  Wild 
Rice,  which  passes  north  of  the  Head  of  the  Coteau  and  enters  the  area  of 
Lake  Agassiz  near  Wyndmere.  The  lowest  portion  of  the  watershed  on 
this  lacustrine  deposit,  over  which  the  James  River  would  flow  east  to  the 
Wild  Rice  River,  is  scarcely  10  feet  above  the  general  level  of  the  James 
Valley,  or  25  feet  above  the  present  level  of  the  James  River,  being  at 

•This  lake  is  partially  mapped  by  Prof.  Todd  in  Proc.  A.  A.  A.  Si,  Vol.  XXXUI,  1884,  p.  393. 


LAKE  DAKOTA.  267 

Amherst,  on  the  Aberdeen  branch  of  the  Grreat  Northern  Railway,  1,312 
feet  above  the  sea.  The  elevation  of  the  upper  portion  of  the  lake  beds  in 
the  vicinity  of  Oakes,  and  the  lack  of  evidence  that  the  lake  waves  have 
acted  at  any  greater  height  upon  the  adjoining  surfaces  of  undulating  till 
and  morainic  hills,  lead  to  the  conclusion  that  the  highest  shore-line  of  the 
north  end  of  Lake  Dakota  is  not  morjC  than  1,345  feet  above  the  sea,  show- 
ing that  there  was  only  a  shallow  expanse  of  water  above  the  plain  of 
lacustrine  silt.  On  the  north  the  depth  of  the  channel  of  the  inflowing 
James  River,  eroded  apparently  before  the  glacial  retreat  could  permit  an 
eastward  outlet  into  Lake  Agassiz,  indicates  that  the  surfaces  of  land  and 
water  in  the  James  Valley  had  gained  nearly  their  present  relations,  Lake 
Dakota  being  already  drained  away,  when  the  Wild  Rice  River  and  the 
south  end  of  the  Red  River  Valley  were  uncovered  by  the  recession  of 
the  ice-sheet.  It  is  evident,  therefore,  that  the  long  area  of  Lake  Dakota 
has  experienced  only  slight  differential  changes  of  level,  at  least  in  the 
direction  from  south  to  north,  since  the  departure  of  the  ice.  The  James 
River  Valley  is  thus  strongly  contrasted  with  the  northward  uplifting,  that 
has  affected  the  Red  River  Valley,  as  shown  by  the  beaches  of  Lake 
Agassiz,  the  highest  of  which  rises  from  south  to  north  about  6  inches  per 
mile  for  30  or  40  miles  at  its  south  end,  but  a  foot  or  more  per  mile  within 
40  miles  farther  north,  and,  indeed,  has  an  average  northward  ascent  of 
about  1  foot  per  mile  through  an  extent  of  400  miles  along  the  west  side 
of  this  lake  in  North  Dakota  and  Manitoba. 

LAKE    SOURIS. 

As  Lake  Agassiz  gradually  extended  to  the  north,  following  the  reced- 
ing ice  barrier,  it  received  successively  by  three  outlets  the  drainage  of  the 
glacial  lakes  of  the  Saskatchewan  and  Souris  basins.  These  streams  took 
the  course  of  the  Sheyenne,  Pembina,  and  Assiniboine  rivers,  each  bring- 
ing an  extensive  delta  deposit.  With  the  first  retreat  of  the  ice  from  the 
Missouri  Coteau  a  glacial  lake  began  to  exist  in  the  valley  of  the  South 
Saskatchewan  in  the  vicinity  of  the  elbow,  probably  outflowing  at  an  early 
time  by  the  way  of  Moose  Jaw  Creek,  and  through  a  glacial  lake  in  the 
upper  Souris  basin,  to  the  Missouri  near  Fort  Stevenson.  Later  the  out-, 
flow  from  the  Lake  Saskatchewan  may  have  passed  to  the  Lake  Souris  by 


268  THE  GLACIAL  LAKE  AGASSIZ. 

way  of  the  Wascana  River,  after  passing  tlu-ough  a  glacial  lake  which 
probably  extended  from  Regina  60  miles  to  the  west  in  the  upper  Qu'Ap- 
pelle  basin.  When  the  Dakota  ice-lobe  was  melted  back  to  the  vicinity 
of  Devils  Lake  the  drainage  of  Lake  Souris  passed  southeast  by  the  Big 
Coulee,  one  of  the  head  streams  of  the  Sheyenne,  flowing  thence  for  some 
time  southward  by  the  James  River  to  Lake  Dakota,  but  later  eastward 
and  southward  by  the  Sheyenne  into  Lake  Agassiz.  A  manuscript  report 
of  a  reconnoissance  in  North  Dakota  by  Maj.  W.  J.  Twining,  in  1869, 
describes  the  valley  of  the  Big  Coulee  as  125  feet  deep  and  a  third  of  a 
mile  wide,  inclosing  several  shallow  lakes  along  its  course.  "  This  great 
valley,"  he  writes,  "preserves  its  character  to  within  12  miles  of  the  Mouse 
River,  and  connects  through  the  clay  and  sand  ridge  with  the  open  valley 
of  that  stream." 

The  glacial  Lake  Souris  (PI.  XXI)  occupied  the  basin  of  the  Souris  or 
Mouse  River  from  the  most  southern  portion  of  this  river's  looj)  in  North 
Dakota  to  its  elbow  in  Manitoba,  where  it  turns  sharply  northward  and 
passes  through  the  Tiger  Hills.  North  of  the  Somis  basin  an  ai-m  of  this 
lake  extended  along  the  Assiniboine  from  Griswold  and  Oak  Lake  to 
some  distance  above  the  mouth  of  the  Qu'Appelle;  and  the  main  body  of 
the  lake  was  deeply  indented  on  the  east  by  the  high  oval  area  of  Turtle 
Mountain,  an  outlier  of  the  lignite-bearing  Laramie  formation,  which  is 
well  developed  on  the  upper  part  of  the  Souris  River  and  forms,  with  over- 
lying drift  deposits,  the  massive  terrace  of  the  Coteau  du  Missom-i  on  the 
west.  The  length  of  Lake  Souris  was  about  170  miles,  from  latitude  48° 
to  latitude  50°  35',  and  its  maximum  width,  north  of  Turtle  Mountain,  was 
nearly  70  miles. 

Until  the  ice-sheet  west  of  Lake  Agassiz  had  receded  so  far  as  to 
uncover  Turtle  Mountain,  the  glacial  lake  in  the  Souris  basin  continued  to 
outflow  by  the  Sheyenne  and  build  up  its  delta.  Next  its  outflow  passed 
north  of  Turtle  Mountain  by  the  Pembina,  perhaps  after  taking  for  a  brief 
time  the  course  of  the  Badger  Creek,  Lac  des  Roches,  and  the  Mauvaise 
Coulde  to  Devils  Lake  and  the  Sheyenne.  The  channel  of  outlet  by 
the  Pembina,  extending  about  110  miles  from  the  elbow  of  the  Souris  to  the 
Pembina  delta  of  Lake  Agassiz,  is  eroded  100  to  300  feet  in  depth,  proba- 
bly averaging  175  feet,  along  the  greater  part  of  its  course,  but  it  is  from 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.  XXI 


s  BitN  a  Co  ^ 


Lake  Ai'eas 


MAP  t)F  THE  GLACIAL  LAKK   SOUKIS. 

Scale,  20  iiiilos  lo  an  incli  . 

Delias  I J         Moi-aincs 


.■lltiuides  of  Railway  stiuions  are  noted  in   feet  ahove  the  sen 


LAKE  SOUEIS. 


269 


300  to  450  feet  deep,  probably  averaging  350  feet,  along  its  last  25  miles. 
It  is  cut  tlu'ough  the  plateau  of  Fort  Pierre  shale  that  reaches  westward 
from  the  Pembina,  Mountain  escarpment.  Outside  of  this  valley  the  shale 
is  overlain  by  only  a  thin  sheet  of  till,  which  varies  generally  from  10  to 
30  or  40  feet  in  thickness;  but  the  valley  itself  contains  a  considerably 
greater  depth  of  till.  From  Lakes  Lome  and  Louise  to  its  delta  the  Pem- 
bina probably  flows  in  its  preglacial  course,  where  its  old  valley  became 
partly  filled  with  till,  during  the  Glacial  period.  The  topographic  features 
of  this  valley  will  be  more  fully  shown  by  the  following  notes  of  approxi- 
mate elevations  referred  to  the  sea-level,  those  of  the  first  column  being 
in  the  bottom  of  the  valley,  and  those  of  the  second  along  the  top  of  its 
blixfi^s  at  the  general  level  of  the  adjoining  country. 

Eleriations  along  the  Pembina  Valle;/  (outlet  of  Lake  Souris). 


Locality. 


Distance 

in  miles 

from  tbe 

elbow 

of  the 

Souris. 


Feet  above 
the  sea  for 
bottom  of 
the  valley 
and  surface 
of  water  in 
rivers  and 
lakes. 


Feet  above 
the  sea  for 
tipp  of  the 
bluffs  in- 
closing the 
valley. 


Elbow  of  the  Sonris,  in  a  valley  that  has  been  eroded  about  100  feet  by  the  present 
river  iiowiug  to  the  Assiniboine  since  the  glacial  Lake  Souris  ceased  to  outflow  to 
the  Pembina  by  Langs  Valley 

Divide  in  Langs  Valley,  near  the  line  between  sections  31  and  32,  township  5,  range  17, 
Manitoba,  separating  Langs  Creek,  flowing  west  to  the  Souris,  and  Duulops  Creek, 
flowing  east  to  the  Pembina,  determined  by  railway  survey 

Bone  Lake,  3  miles  long  and  a  half  mile  wide 

Grass  Lake 

Pelican  Lake,  10  miles  long  and  about  a  mile  wide,  mostly  10  to  15  feet  deep,  but  in  its 
deepest  portions  about  20  feet,  rising  3  feet  between  its  lowest  and  highest  stages. . 

Junction  of  outlet  of  Pelican  Lake  with  the  Pembina - 

Lake  Lome;  area,  about  1  mile  square;  maximum  depth,  about  8  feet 

Lake  Louise,  of  nearly  the  same  area  and  maximum  depth 

Mouth  of  Badger  Creek : 

Rock  Lake,  8  miles  long  and  one-half  to  1  mile  wide;  maximum  depth,  10  feet' 

Mouth  of  Clearwater  River 

At  the  Marringhurst  bridge,  on  the  north  line  of  section  16,  township  3,  range  12, 
Manitoba 

Swan  Lake,  5  miles  long  and  1  mile  wide ;  maximum  depth,  probably  about  10  feet 

At  La  Riviere,  determined  by  railway  survey 

At  crossing  of  the  boundary  commission  road^ 

At  crossing  of  tbe  old  Missouri  trail 

At  the  Mowbray  bridge,  on  tbe  line  between  sections  21  and  22,  township  1,  range  8, 
Manitoba 

On  tbe  international  boundary 

At  the  fish  trap,  section  30,  township  163,  range  57,  North  Dakota,  2  miles  west  of  the 
Pembina  Mountain  escarpment  and  7  miles  west  of  Walhalla 


4 
5-  8 
10-11 

11-21 
22J 

23-24 

25-26 
27 

30-38 
40 

42 
50-55 
67 
75 
80 

85 
100 


1,364 
1,357 
1,355 

1,355 
1,348 
1,346 
1,345 
1.343 
1,335 
1,332 

1,330 
1,310 
1,287 
1,265 
1,250 

1,235 
1,125 


1,475 
1,480 
1,485 

1,  485-1,  510 
1.510 
1,510 
1,510 
1,510 

1, 510-1,  550 
1,525 

1,480 
1,500 
1,550 
1,550 
1,545 

1,540 
1,540 

1, 400-1,  500 


'Glenora  prairie,  north  of  Rock  Lake,  a  slightly  undulating  exp.anse  of  modified  drift,  stratified  gravel,  and  sand, 
extending  6  miles  from  west  to  east  and  2  to  3  miles  wide,  has  an  elevation  of  1,510  to  1,500  feet,  descending  eastward  with 
tlie  valley. 

2  Dr.  George  M.  Dawson  notes  a  wide  terrace  here,  in  some  places  thickly  strewn  with  bowlders,  on  the  southwestern 
side  of  the  river  and  about  200  feet  above  it;  and  he  refers  its  origin  to  preglacial  erosion  of  the  valley. 


270  THE  GLACIAL  LAKE  AGASSIZ. 

At  the  Mowbray  bridge  the  bottom  land  is  about  an  eighth  of  a  mile 
wide  and  10  feet  above  the  river.  About  40  feet  higher  is  a  naiTow  terrace 
of  modified  drift,  an  eighth  to  a  fourth  of  a  mile  wide,  reaching  along  the 
southern  side  of  the  river  for  li  miles  to  the  east,  and  also  well  shown  in 
many  places  on  each  side  of  the  river  for  6  miles  or  more  both  to  the  west 
and  east;  but  along  much  of  this  distance  one  or  both  sides  of  the  valley 
slope  gradually  from  100  or  75  feet  above  the  river  to  the  bottom  land.  The 
higher  portions  of  the  sides  or  bluffs  of  the  valley  have  steep  slopes,  rarely 
interrupted  by  terraces.  But  a  remarkably  broad  ten-ace  or  plateau,  evi- 
dently formed  during  the  preglacial  or  interglacial  erosion  of  this  valley, 
extends  on  its  southern  side  3  miles  to  the  east  from  tlie  IMowbraj^  bridge 
and  road,  with  a  maximum  width  of  about  IJ  miles,  and  an  elevation  of 
1,450  to  1,425  feet  above  the  sea,  or  about  200  feet  above  the  river.  A 
lakelet  half  a  mile  long  from  east  to  west  lies  on  the  southern  part  of  this 
plateau  at  the  foot  of  the  bluff  that  rises  thence  about  100  feet  to  the 
general  level  of  the  adjoining  country.  All  the  way  for  25  miles  from  this 
bridge  to  the  Pembina  delta,  especially  in  the  vicinity  of  the  fish  trap,  tlie 
river  flows  in  a  very  picturesque  valley,  Avhose  sides,  rising  steeply  300  to 
450  feet,  are  roughly  seamed  and  cleft  by  tributary  ravines  and  gorges, 
with  here  and  there  hills  and  small  plateaus  that  have  been  left  isolated  by 
the  process  of  erosion.  This  valley  has  fi-equent  exposures  of  the  Fort 
Pierre  shales,  which  also,  within  a  half  mile  to  1  mile  back  from  the  river, 
form  the  high  plateau  tlu'ough  which  the  river  has  cut  its  way  The  nar- 
rowness and  depth  of  the  partially  di-ift-filled  valley  indicate  that  its  area 
of  drainage  was  no  greater  in  preglacial  time  than  now. 

The  mouth  of  Lake  Souris  where  it  first  outflowed  to  Lake  Agassiz  by 
the  Big  Coulee  and  the  Sheyenne  was  approximately  1,600  to  1,500  feet 
above  the  present  sea-level,  being  gradually  cut  down  about  100  feet  by 
the  stream.  But,  on  account  of  subsequent  changes  which  are  known  to 
have  taken  place  in  the  relative  elevation  of  the  land  and  water  surfaces  in 
this  district,  the  shore-line  of  the  northern  part  of  the  lake  at  the  end  of  its 
time  of  outflow  to  the  Sheyenne  would  now  have  an  elevation  of  about 
1,600  feet  at  Langs  Vallej^  Therefore,  when  its  channel  of  discharge  was 
transferred  to  the  new  course  by  Pelican  Lake  and  along  the  Pembina,  the 


LAKE  SOUEIS  AND  LANGS  VALLBT.  271 

Lake  Souris  was  suddenly  lowered  about  125  feet  to  the  level  of  the  top 
of  the  bluffs  of  Langs  Valle}^,  and  a  further  lowering  of  110  feet  was  after- 
ward effected  by  the  gradual  erosion  of  this  valley.  The  lake  was  wholly 
drained  by  this  outlet,  for  the  general  level  of  the  land  adjoining  the  Souris 
in  the  ^dcinity  of  the  mouth  of  Plum  Creek,  which  is  the  lowest  portion  of 
the  lake  bed,  is  about  20  feet  above  the  present  divide  in  Langs  Valley. 
Since  the  waters  of  the  Souris  ceased  to  flow  along  this  course,  the  sedi- 
ments of  gravel  and  sand  brought  by  tributaries  have  filled  portions  of  the 
Pembina  Valley  10  to  20  feet,  forming  the  bamers  of  its  shallow  lakes; 
and  the  divide  in  Langs  Valley  has  been  raised  probably  10  feet  by  the 
deposits  of  Dunlops  Creek. 

The  ice-sheet  was  forming  its  moraine  of  the  west  part  of  the  Tiger 
Hills,  and  of  the  Brandon  and  Arrow  hills,  when  Lake  Souris  began  to  out- 
flow by  the  course  of  Langs  Valley  and  the  Pembina.  The  extent  of  Lake 
Souris  was  then  from  the  northern  part  of  North  Dakota  along  the  Souris 
and  Assiniboine  to  the  lower  Qu'Appelle;  and  the  Saskatchewan  outflow 
by  its  erosion  of  the  Qu'Appelle  Valley  brought  into  this  lake  extensive 
delta  deposits  of  gravel  and  sand,  which,  with  similar  beds  of  modified  drift 
brought  into  it  from  the  melting  ice-sheet  that  was  its  northeastern  ban'ier, 
reach  from  the  vicinity  of  Fort  Ellice  southeast  to  Oak  Lake  and  Plum 
Creek. 

After  the  erosion  of  Langs  Valley  had  lowered  the  Lake  Som-is  below 
the  level  (about  1,390  feet)  at  which  its  outflow  could  pass  instead  to  the 
north  and  northeast  by  the  way  of  Oak  Lake  and  the  Assiniboine,  the  ice 
was  withdrawn  to  the  north  side  of  the  Assiniboine  Valley  east  of  Oak 
Lake,  and  the  deposition  of  the  g^eat  Assiniboine  delta  of  Lake  Agassiz 
ensued.  A  width  of  onlv  3  miles  of  the  morainic  belt  of  the  Tiger  Hills, 
extending  along  the  north  side  of  Langs  Valley  and  the  elbow  of  the 
Souris,  intervened  between  that  stream  and  an  expanse  of  till  whose  surface 
is  lower  than  the  bottom  of  Langs  Valley  and  descends  with  northeastward 
slope  to  the  Assiniboine.  The  crest  of  this  moraine  rises  about  200  feet 
above  Langs  Valley,  but  it  had  probably  been  cut  through  nearly  or  quite 
to  the  level  of  that  valley  by  drainage  southward  from  a  small  lake  formed 
between  the  moraine  and  the  receding  ice  within  the  angle  between  the 


272  THE  GLACIAL  LAKE  AGASSIZ. 

east-to-west  range  of  the  Tiger  Hills  and  the  noi'th- to-south  range  of 
the  Brandon  Hills.  With  the  withdrawal  of  the  ice  front  across  the  Assini- 
boine  this  gap  through  the  moraine  was  soon  channeled  deeper,  and  the 
Soui'is  turned  northward  at  its  elbow,  leaving  its  old  channel  of  Langs 
Valley  and  flowing-  with  more  rapid  descent  to  the  Assiniboine  in  its  pres- 
ent course.  The  gap  has  been  since  ei'oded  to  a  total  depth  of  350  feet; 
and  thence  northward  the  Soiiris  has  cut  a  channel  about  140  feet  deep, 
chiefly  in  till,  which  forms  steep  blufl's  that  in  many  places  are  now  being 
undermined  by  the  stream.  Erosion  along  this  part  of  the  Soui-is  is  still 
proceeding  rapidly,  and  the  valley  has  a  very  new  appearance. 

LAKE    SASKATCHEWAN. 

Through  the  whole  period  of  the  existence  of  Lake  Souris,  which  at 
first  outflowed  to  the  Missouri  and  afterward  to  Lake  Agassiz,  the  glacial 
lake  in  the  basin  of  the  South  Saskatchewan,  doubtless  also  at  last  including 
the  North  Saskatchewan,  was  tributary  to  it,  and  the  outlet  of  this  Lake 
Saskatchewan  was  transferred  to  lower  courses  as  the  border  of  the  ice- 
sheet  receded  from  southwest  to  northeast.  When  the  upper  part  of  the 
QuAppelle  became  uncovered,  but  its  lower  portion  remained  enveloped 
by  the  ice,  the  Saskatchewan  outflow  probably  passed  to  Lake  Souris  suc- 
cessively by  the  Moose  Jaw  Creek  and  the  upper  Souris,  by  the  Wascana 
and  the  Moose  Mountain  Creek,  and  by  the  Summerberry  and  Pipestone 
creeks.  Finally  the  whole  length  of  the  Qu'Appelle  was  uncovered,  and 
the  great  glacial  river  from  Lake  Saskatchewan  flowed  along  the  course  of 
this  valley,  which  is  similar  to  that  of  the  Pembina  in  its  width  and  depth 
and  the  numerous  lakes  along  its  bottom.  At  first  this  river  crossed  the 
divide  between  the  River  that  Turns  and  the  head  of  the  Qu'Appelle, 
where  it  eroded  a  trough-like  channel  like  that  of  Browns  and  Langs 
valleys;  but  later  it  probably  found  a  lower  outlet  .farther  north,  flowing 
southward  to  the  Qu'Appelle  through  the  valley  of  Long  or  Last  Mountain 
Lake. 

The  following  table,  compiled  from  Hind's  report  of  the  Assiniboine 
and  Saskatchewan  exploring  expedition,  brings  into  view  the  remarkable 
topographic  features  of  the  Qu'Appelle  Valley,  and  shows  the  lengths  and 


LAKE  SASKATCHEWAN. 


273 


maximiim  depths  of  the  lakes  through  which  the  river  flows.  Its  elevations 
are  referred  to  sea-level,  approxiraately,  by  comparison  with  the  Canadian 
Pacific  Railway. 

Elevations  along  the  Qu'Appelle  Valley  (outlet  of  Lake  Saskatchewan). 


Locality. 


Miles  from 
elbow  of  the 
South  Sas- 
katchewan 


Elbow  of  the  South  Saskatchewan. 

Ponds  on  the  Kiver  that  Turns 

Height  of  land 

Sand  Hill  or  Eyebrow  Lake 

Buffalo  Lake 

Lake 

Fourth  Fishing  Lake 

Third  Fishing  Lake 

Second  Fishing  Lake 

First  Fishing  Lake 

Crooked  Lake 

Round  Lake 

Mouth  of  the  Qu'Appelle 


7-    8 

12 

24-  28 

58-  74 

83-  84 

135-144 

144-149 

150-153 

154-160 

198-203 

218-223 

268 


Feet  above 
the  sea. 


1,619 
1,686 
1,704 
1,685 
1,635 
1,624 
1,604 
1,503 
1,501 
1,500 
1,389 
1,364 
1,264 


Maximum 

depths  of 

lakes  in 

feet. 


*10 


*20 
•20 
•15 
54 
57 
48 
66 
36 
30 


Height  of 

bluffs  in 

feet. 


140 

110 

110-140 

116-150 

190 

185 

270 

270 

275 

300-350 

300-320 

310 

220 


*  About. 


The  area  that  was  occupied  by  the  glacial  Lake  Saskatchewan  during 
its  stages  of  outflow  through  the  head  stream  of  the  Qu'Appelle,  afterward 
by  Long  Lake,  and  perhaps  still  later  by  the  head  stream  of  the  Assini- 
boine,  extends  from  the  base  of  the  morainic  Vermilion  Hills,  on  the  Mis- 
souri Coteau,  where  it  is  cut  through  by  the  South  Saskatchewan,  some  25 
miles  above  its  elbow,  to  the  eastern  part  of  the  Pasquia  Hills,  south  of  the 
Cumberland  House.  At  length  the  glacial  recession  opened  the  Lower 
Saskatchewan  Valley,  and  this  lake  fell  to  the  level  of  Lake  Agassiz,  which 
appears  to  have  reached  up  the  Saskatchewan  to  the  vicinity  of  Prince 
Albert,  about  40  miles  above  the  confluence  of  its  north  and  south  branches. 
Before  the  ice  dam  between  Lakes  Saskatchewan  and  Agassiz  was  removed, 
the  former  lake,  as  here  described,  had  covered  an  area  approximately  300 
miles  long  and  25  to  75  miles  wide. 

It  is  to  be  added,  however,  that  before  the  Saskatchewan  Lake  was 
permitted  by  the  glacial  retreat  to  fill  a  part  of  the  basin  so  far  east  as  to 
outflow  into  the  Qu'Appelle,  various  bodies  of  water,  dammed  by  the  ice- 
sheet,  had  existed  in  its  upper  portions,  flowing  southward,  as  noted  in  the 
early  part  of  this  chapter,  by  Lake  Pakowki  and  other  courses.  If  we 
MON  XXV 18 


274  THE  GLACIAL  LAKE  AGASSIZ. 

could,  by  a  ^asion  of  the  past,  see  in  detail  all  the  successiA^e  glacial  lakes 
of  Alberta,  Saskatchewan,  and  Assiniboia,  and  the  old  rivers  flowing  from 
them  over  the  present  watersheds,  there  would  surely  be  revealed  a  very 
complex  history,  which  future  glacialists  can  hope  to  discover  only  by 
much  patient  exploration. 

GLACIAL  LAKES  OF  THE  PEACE  AND  ATHABASCA  BASINS. 

In  the  preceding  chapter  I  have  shown  that  the  ice-sheet  probably 
stretched  as  one  continuous  mer  de  glace  from  the  Atlantic  to  the  Pacific, 
wholly  covering  the  Rocky  Mountains  in  then-  low  portion  adjoining  the 
Peace  River.  Its  thickness  there  may  have  been  3,000  to  5,000  feet, 
and  from  this  central  part  its  surface  sloped  downward  both  to  the  south 
and  north.  During  the  depai-ture  of  the  ice,  therefore,  its  southern  border 
in  this  region,  as  elsewhere  along  its  entire  extent  across  the  continent, 
retreated  in  general  toward  the  north,  with  embayments  here  and  there 
between  projecting  ice-lobes.  Thus  there  came  a  time  when  the  Peace 
River  basin  had  become  mostly  or  wholly  uncovered  from  its  icy  mantle, 
and  held  a  lake  shut  in  on  the  north  by  the  receding  glacial  barrier.  West 
of  the  one  hundred  and  seventeenth  meridian,  according  to  Dr.  Gr.  M.  Daw- 
son, the  elevated  plains  which  are  intersected  by  the  deep  valleys  of  the 
Peace  and  Smoky  rivers  and  their  tributaries  are  overspread  by  fine  lacus- 
trine silts  lying  on  the  glacial  drift.^  The  elevation  of  this  silt-enveloped 
country  ranges  from  2,000  to  2,500  feet  above  the  sea,  and  it  may  be 
merely  a  vast  delta  occupying  but  a  small  part  of  the  fully  expanded 
Peace  Lake. 

The  earliest  outlet  from  this  glacial  lake  probably  flowed  across  the 
present  watershed  between  the  Peace  River  and  Lesser  Slave  Lake,  which 
is  about  2,430  feet  above  the  sea;  and  then,  after  passing  tkrough  a  smaller 
glacial  lake,  or  confluent  part  of  the  Peace  Lake,  in  the  upper  Athabasca 
basin,  it  may  have  passed  across  the  divide  between  the  Tow-ti-now  River 
and  the  North  Saskatchewan,  on  or  near  the  trail  from  Athabasca  Landing 
to  Edmonton.  The  height  of  this  watershed  is  about  2,485  feet.  Later 
stages  of  the  glacial  retreat  would  give  successively  lower  outlets,  until  the 

1  Oeol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1879-80,  p.  142  B;  Trans.,  Royal 
Society  of  Canada,  Vol.  VIII,  sec.  i,  1890,  p.  47. 


PEACE  AND  ATHABASCA  GLACIAL  LAKES,  275 

depression  of  the  watershed  at  the  Methy  portage  probably  afforded,  as 
remarked  on  a  foregoing  page,  the  lowest  and  latest  channel  of  outflow 
from  the  Mackenaie  basin  to  Lake  Agassiz. 

The  watercourse  by  which  the  Churchill,  bringing  the  Peace  and 
Athabasca  outflow,  passed  into  the  Saskatchewan,  tributary  to  Lake  Agas- 
siz, begins  at  Frog  portage  and  extends  south-southeastward  about  100 
miles  by  a  Lake  of  the  Woods,  Pelican,  Heron,  and  Birch  lakes.  Great 
and  Ridge  rivers,  Beaver,  Sturgeon,  and  Pine  Island  lakes,  to  the  Sas- 
katchewan at  Cumberland  House.  This  was  the  route  of  Franklin  and 
Richardson  in  1820.  The  latter  states  that  "by  Beaver  Lake  and  its  cham 
of  waters  Nelson  River  receives  supplies  from  the  very  banks  of  the  Mis- 
sinippi  or  Churchill  River.  Indeed,  the  Beaver  Lake  chain,  which  lay  in 
our  route,  originates  within  a  hundi-ed  yards  of  the  latter  sti-eam."  Frog 
portage,  at  this  locality,  "is  380  paces  long.  The  path  leads  through  a  low, 
swampy  wood,  and  over  a  flat  tract  of  gneiss  rising  only  a  few  feet  above 
the  waters  on  each  side."  The  further  descriptions  of  their  journey  up  the 
Churchill,  which  "resembles  a  chain  of  lakes  with  many  amis,  more  than 
a  river,"  and  by  Isle  k  la  Crosse  Lake,  Deep  River,  Clear  and  Bufialo  lakes, 
and  Methy  River  and  Lake  to  Methy  portage,  indicate  that  this  was  at  one 
time  the  avenue  of  outflow  from  a  glacial  lake  in  the  Mackenzie  basin.  Isle 
k  la  Crosse,  Clear,  and  Buflklo  lakes,  which,  according  to  Macoun,  have  the 
same  level,  being  stagnant  water,  filled  with  green  scum  in  summer,  are 
approxunately  1,500  feet  above  the  sea;  Methy  Lake,  1,700  feet;  the  crest 
of  Methy  portage,  1,760  feet,  abundantly  strewn  with  bowlders,  probably 
belonging  to  a  belt  of  morainic  drift;  and  Clearwater  River,  a  tributary  of 
the  Athabasca,  at  the  north  end  of  this  portage,  1,100  feet.  A  very  steep 
descent  is  made  to  the  Clearwater,  which  flows  westward  in  a  great  valley, 
formed  by  preglacial  erosion,  2  to  3  miles  wide.^ 

■Narrative  of  a  journey  to  the  shores  of  the  Polar  Sea,  in  the  years  1819,  1820,  1821,  and  1822,  by 
John  Franklin,  R.  N.,  F.  R.  S. ;  including  an  Appendix  of  Geognostical  Observations  by  John  Rich- 
ardson, M.  D.,  surgeon  to  the  expedition. 

Also,  see  Sir  John  Richardson's  Arctic  Expedition  in  Search  of  Sir  John  Franklin;  and  descrip- 
tions of  Methy  portage  and  its  vicinity,  by  Prof.  John  Macoun  (Geol.  Survey  of  Canada,  Report  of 
Progress  for  1875-76,  pp.  94,  174)  and  by  Dr.  Robert  Bell  (Bulletin,  G.  S.  A.,  Vol.  I,  p.  290). 

The  elevations  stated  are  increased  200  feet  above  the  estimates  given  by  Richiirdson,  which 
addition  (or  perhaps  100  feet  more)  is  required  by  comparison  with  reliable  determinations  of  eleva- 
tions on  the  Saskatchewan  and  Peace  rivers. 


CHAPTER  VI. 
BEACHES  AND  DELTAS  OF  THE  HERMAN  STAGES. 

In  tliis  and  the  two  following  chapters  the  shore-lines  of  Lake  Agassiz 
are  described  in  considerable  detail,  with  notes  of  their  altitude  and  of  the 
topographic  features  of  their  tracts  marked  by  erosion,  and  of  the  more 
extensive  ti'acts  where  beach  ridges  were  accumulated.  The  fullness  and 
convincing  character  of  the  evidence  that  these  are  the  shore-lines  of  an 
ancient  lake  of  vast  size,  occupying  the  Red  River  Valley  and  the  present 
lake  region  of  Manitoba,  are  thus  impressively  exhibited;  and  the  diverse 
phases  of  the  results  produced  by  waves  and  shore  cun-ents  are  brought 
into  comparison. 

Ten  plates  (XXIII  to  XXXII),  on  the  scale  of  6  miles  to  an  inch, 
covering  consecutive  areas  as  indicated  on  PI.  XXII,  display  the  definite 
geographic  location  of  the  shores;  and  all  their  more  remarkable  portions 
are  described,  with  statement  of  the  sections  or  often  the  quarter-sections 
under  consideration,  in  the  text.  The  arrangement  of  the  sections  in  each 
township  is  shown  in  fig.  1,  on  page  11. 

Many  of  the  farmers  whose  houses  are  built  on  or  near  to  the  old 
beaches  have  decided  to  theii-  own  satisfaction,  as  I  learned  by  conversation 
with  them  during  the  progi-ess  of  these  surveys  and  levelings,  that  these 
beach  ridges  of  gravel  and  sand  are  the  same  as  those  of  now  existing  lakes 
of  large  size,  and  that  consequently  the  flat  Red  River  Valley  so  bounded 
was  once  the  bed  of  a  great  lake.  These  residents  will  be  enabled  by  the 
following  descriptions  and  maps  to  trace  the  continuity  of  the  shores  seen 
near  their  own  homes  to  distances  of  many  miles  away  and,  indeed,  around 
all  the  prairie  portion  of  the  ancient  lake. 

With  the  progress  of  agriculture,  which  is  rapidly  bringing  all  this  lake 
bed  into  cultivation,  certain  features  of  the  deserted  shores  that  were  very 
distinct  at  the  time  of  my  examination  will  doubtless  be  obscured  or  oblit- 
erated.    Many  of  the  groves  here  noticed  as  occun-ing  along  stream  courses 

276 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH    XXV.    PL.XXll 


s  eitN  s  ca  N V 


MAJ^  OF  THE  SOUTHERN  PORTION  OF  LAIvE  AGASSIZ  EXPLORED  WTII  LEVELr.ING  IN  MINNESOTA, 

NORTH  DAIiOTA,  AND  MANITOBA,  SHOWING  THE  LOCAITON  OP  PLATES  XXm-XXXn. 

Scale,  about  ^2  milfs  to  an  inch. 

Areaof  Lake  Agassiz  I I  Terminal  Moraines  LiciLJ 


ANNUAL  OSCILLATIONS.  277 

or  elsewhere  in  the  neighborhood  of  the  old  shore-lines  will  probably  cease 
to  exist  within  a  century,  or  in  some  cases  within  a  score  of  years.  On  the 
other  hand,  many  artificial  groves  surrounding  farmhouses,  and  lines  of  trees 
cultivated  on  the  divisions  of  property  or  of  adjacent  fields,  will  probably 
more  than  replace  such  loss,  making  the  country  more  beautiful  and  less 
liable  to  be  stvept  heavily  by  winds.  But  the  extensive  views  enjoyed 
by  the  writer  and  his  assistant  rodman  as  they  advanced  along  the  course 
of  the  beaches,  mapping  them  and  determining  their  elevation,  will  be 
then  hindered  by  the  cultivated  groves,  tree  rows,  and  hedges.  Only  upon 
a  prauie  country,  such  as  this  was  when  its  shore-lines  were  first  traced, 
can  the  grandeur  of  the  proofs  of  existence  of  glacial  lakes,  held  by  the 
obstruction  of  the  departing  ice,  be  taken  in  by  an  unimpeded  vision  of 
the  smooth  lake  bottom  on  one  side  stretching  out  to  a  distance  of  10  or  20 
miles  within  sight,  of  the  bordering  beach,  running  as  one  unbroken  ridge 
of  gravel  and  sand  in  a  nearly  direct  course  discernible  for  several  miles, 
and  of  the  broad,  slightly  higher  expanse  of  more  undulating  and  knolly 
glacial  drift  outside  the  lake  area. 

From  these  descriptions  of  the  beach  ridges  and  eroded  shores  of  the 
old  lake,  its  levels  at  the  time  of  formation  of  these  shore-lines  are  deduci- 
ble  approximately.  The  elevations  of  the  crests  of  the  beach  ridges,  as 
recorded  in  these  notes,  are  commonly  5  to  10  feet,  or  rarely  15  feet  or 
more,  above  the  level  held  by  the  lake  when  the  beaches  were  heaped  up 
by  the  waves,  chiefly  during  storms.  Where  the  descents  of  the  slopes  of 
these  gravel  and  sand  ridges  are  noted,  the  lake  level  was  nearly  always 
below  the  depression  which  borders  the  landward  side  of  the  beach  and 
was  near  the  foot  of  the  lakeward  slope.  Cliifs  eroded  by  the  lake  waves 
give  more  definitely  the  plane  of  the  water  surface  which  cut  into  the  base 
of  the  eroded  escarpment,  usually  consisting  of  till,  undermining  it  and  car- 
rying away  its  material  to  form  a  very  gently  descending  slope,  which  was 
covered  by  the  margin  of  the  lake. 

Fluctuations  of  the  lake  level,  which  doubtless  rose  in  summer  a  few 
feet  higher  than  in  winter,  because  of  the  A^ariations  in  the  volume  of  water 
supplied  from  the  melting  ice-sheet,  have  given  a  variability  within  limits 
generally  5  feet  and  perhaps  sometimes  8  or  10  feet  apart  to  the  heights  of 


278  THE  GLACIAL  LAKE  AGASSIZ. 

the  lake  and  of  its  shore  deposits  and  planes  of  erosion  in  each  of  the  more 
than  thirty  stages  which  these  shore-lines  exhibit.  The  high-water  surface 
of  the  summers,  however,  had  probably  a  nearly  uniform  elevation  dm'iug 
many  years  in  each  stage,  producing  therefore  a  beach  or  eroded  line  of 
nearly  constant  height.  On  the  other  hand,  the  reduced  lake  level  of  the 
winters,  when  the  superficial  melting  of.  the  ice-sheet  ceased  and  the  lake 
doubtless  became  mostly  frozen  over,  was  likewise  at  nearly  the  same  ele- 
vation from  year  to  year;  but  the  beach  ridges  formed  by  the  strong  wave 
action  of  the  autumn,  winter,  and  spring  storms,  with  the  effects  of  the 
di'ifting  lake  ice  during  the  breaking  up  in  spring,  would  be  mostly  washed 
away  by  the  ensuing  high  water  of  the  summer,  when  the  glacial  melting 
attained  its  maximum.  As  the  result  of  these  annual  oscillations  of  the  lake 
sm-face,  gravel  and  sand  from  the  material  eroded  during  the  storms  of 
winter,  both  from  bordering  cliffs  and  from  the  shallow  lake  bed  close  along 
the  shore,  have  been  chiefly  preserved  in  beach  deposits  at  the  higher  plane 
of  the  fluctuation  reached  in  summer. 

Periodic  oscillations  occupying  several  years  between  successive  max- 
ima of  the  lake  level  were  also  probably  caused  by  cycles  of  increase  and 
diminution  in  temperature  and  rainfall,  with  consequent  irregularity  in 
the  yearly  amount  of  the  glacial  melting.  The  cycles  of  rise  and  fall 
of  the  great  Laurentian  lakes  have  a  somewhat  uniform  average  length  of 
ten  to  twelve  years,  as  stated  in  Chapter  XI,  the  maximum  heights  of  these 
lakes  being  5  to  6  feet  above  their  lowest  recorded  stages.  But,  on  account 
of  the  great  variation  of  the  tribute  received  by  Lake  Agassiz  from  the 
departing  ice-sheet  in  the  alternating  warm  and  cold  portions  of  each  year, 
probably  its  annual  fluctuations  of  level  equaled  or  exceeded  the  changes 
of  longer  periods  in  the  Laurentian  lakes,  which  receive  a  somewhat  steady 
supply  through  all  the  seasons,  but  are  raised  by  excess  of  rainfall  during 
a  few  years  together  and  then  lowered  by  a  series  of  drier  years. 

THE    UPPER    OR    HERMAN    BEACHES    AND    DELTAS    IN    MINNESOTA. 

Our  description  of  the  highest  shore-lines  of  Lake  Agassiz  may  well 
begin  at  the  mouth  of  this  lake,  the  present  site  of  the  northern  end  of 
Lake   Traverse.     Thence   the   uppermost   or   HeiTnan    beach  was  traced 


THE  UPPEE  OR  HEEMAN  BEAOHES  AND  DELTAS.  279 

eastward  and  northeastward  tln-ough  Traverse  County  and  the  most  north- 
western township  of  Stevens  County,  Minn.,  to  Herman,  in  Grant  County, 
nearly  20  miles  east  of  Lake  Traverse.  From  this  place  the  Herman  beach 
runs  nearly  due  north  132  miles  to  the  north  side  of  Maple  Lake,  in  Polk 
County,  about  20  miles  east-southeast  of  Crookston.  Beyond  Maple  Lake 
the  course  of  this  shore-line  is  known  to  be  nearly  east  to  the  south  side 
of  Red  and  Rainy  lakes;  but  it  passes  through  a  wooded  and 'uninhabited 
country  where  it  is  impracticable  to  trace  its  course  exactly  and  determine 
its  height  by  leveling. 

Along  the  distance  of  about  160  miles,  as  measured  by  long,  straight 
lines,  or  about  175  miles,  following  the  larger  bends  of  the  shore-line,  from 
Lake  Traverse  to  Herman  and  Maple  Lake,  the  boundary  of  Lake  Agassiz 
lies  in  a  prairie  region,  mostly  having  a  very  smooth  and  regular  surface, 
which  coiild  not  be  surpassed  in  its  adaptability  for  receiving  and  preserv- 
ing a  record  of  the  old  lake  level.  The  Herman  beach  lines,  single  on  the 
southern  part  of  the  lake  border,  but  double  and  even  quadruple  in  Clay 
County  and  northward,  have  been  carefully  mapped  across  this  expanse  of 
prairie,  and  their  heights  have  been  determined  by  leveling.  The  principal 
features  of  this  series  of  beaches  are  described  in  the  following  pages. 

Especial  description  is  also  given  of  the  two  chief  delta  deposits  of 
this  part  of  the  old  lake  border.  These  were  brought  into  the  lake,  con- 
temporaneously with  the  formation  of  the  Herman  beach,  by  the  glacial 
representatives  of  the  Buffalo  and  Sand  Hill  rivers.  They  cover  small 
areas,  in  comparison  with  the  Sheyemie,  Elk  Valley,  Pembina,  and  Assini- 
boine  deltas  on  the  west  margin  of  this  glacial  lake. 

FROM    LAKE    TRAVERSE    EAST    TO    HERMAN. 

(Pr.ATE   XXIII.) 

Within  the  first  4  miles  eastward  from  the  northeast  end  of  Lake 
Traverse  the  Herman  shore  of  Lake  Agassiz  •  is  an  eroded  bluff  of  till, 
rising  from  the  south  side  of  the  Mustinka  River  to  a  height  of  75  to  100 
feet  above  the  river  and  lake.  The  altitude  of  Lake  Traverse  at  its  low- 
est and  highest  »stages  is  970  and  976  feet  above  mean  tide  sea-level. 
When  the  lake  falls  below  973  or  972  feet,  which  occurs  during  the  dry 


280  THE  GLACIAL  LAKE  AGASSIZ. 

season  neany  every  summer,  it  ceases  to  outflow  by  the  Bois  des  Sioux, 
aud  that  stream  becomes  reduced  to  a  series  of  stagnant  pools.  The  eroded 
bluff  noted,  aud  others  of  the  same  character  lying-  on  each  side  of  the 
Bois  des  Sioux  at  a  distance  of  3  to  4  miles  apart  between  Lake  Traverse 
and  White  Rock,  were  finished  by  the  outflow  of  the  glacial  River  War- 
ren, but  probably  their  erosion  was  begun  by  a  stream  outflowing  here 
from  the  Red  River  Valley  during  the  Aftonian  interglacial  stage  between 
the  Kansan  and  lowan  stages  of  ice  accumulation  and  extension.^ 

After  following  the  old  lake  shore  eastward  to  a  distance  of  about  4 
miles  from  Lake  Traverse,  the  steep  bluff  gives  place,  in  sections  2  and  11, 
Walls,  to  a  gentle  slope  of  the  surface,  which  allowed  the  accumulation  of 
a  distinct  beach  ridge  of  gravel.  Tliis  is  smoothly  rounded,  15  to  20  rods 
in  width,  bounded  eastward  on  the  side  toward  the  ancient  lake  by  a  mod- 
erately steep  slope  which  descends  10  or  12  feet,  the  land  1  to  4  miles 
distant  northeastward  within  the  area  that  was  covered  by  the  lake  being 
20  to  40  feet  below  this  beach.  On  the  other  side  this  ridge  is  succeeded 
by  a  slight  depression  2  to  5  feet  deep,  beyond  which  the  land  soon  rises 
10  to  15  feet  above  the  beach.  The  material  of  the  beach  is  gravel,  con- 
taining pebbles  up  to  2  or  3  inches  in  diameter,  but  all  the  sui'face  else- 
where on  each  side  is  till.  The  crest  of  the  beach  here  is  1,060  to  1,062 
feet  above  the  sea. 

The  beach  next  passes  southeastward  tln-ough  sections  30  and  32, 
Croke,  having  in  places  a  maximum  altitude  of  1,067  feet,  being  piled 
several  feet  above  its  average  height. 

Between  2  and  3  miles  farther  southeast,  near  the  middle  of  section 
9,  Tara,  the  beach  ridge  sinks  to  the  height  of  1,057  feet.  Its  contour  and 
material,  and  those  of  the  adjoining  areas,  are  nearly  the  same  as  at  the 
locality  first  described.  The  width  of  the  gravel  beach  here  is  25  or  30 
rods;  the  smoothed  surface  of  till  which  descends  thence  northward  is  10 
to  20  feet  lower  in  its  first  mile;  on  the  south  the  sheet  of  till  is  at  fii-st  for 
40  or  50  rods  about  5  feet  lower  than  the  top  of  the  beach,  but  beyond  this 

'Am.  Geologist,  Vol.  XV,  p.  281,  May,  1895.  The  nomeuelature  of  these  subdivisions  of  the 
Glacial  period  -svas  proposed  by  Prof.  T.  C.  Chamberlin  in  Chapter  XLII  of  James  Geikie's  "The 
Great  Ice  Age,"  third  edition,  1894,  and  more  fully,  first  naming  the  Aftonian  stage,  in  the  Journal  of 
Geology,  Vol.  Ill,  pp.  270-277,  April-May,  1895. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XXIII. 


MAP  OF  LAKES  TRiVVERSE  AND  BIG  STONE i\ND  THE  SHORES  OF  LAKE  AGASSIZ  NEAR  ITS  MOUTH. 

Scale,  G  miles  to  an  inch. 


LakeiVx'ea    w-ith  Beaches 


Delta 


^■\.fffiftd4\s    of    Haifwd-v   sfa/zons    are    noted     in     feet    above    the    scxt  . 


THE  UPPER  OE  HERMAN  BEACHES.  281 

it  gradually  rises  to  a  height  10  to  25  and  50  feet  above  the  beach.  The 
average  height  of  its  moderately  undulating  surface  6  miles  to  the  south,  at 
Graceville,  is  nearly  represented  by  the  railroad  at  the  depot  there,  1,109 
feet.  Farther  to  the  east,  through  this  township,  the  crest  of  the  beach 
ranges  from  1,057  to  1,062  feet. 

For  the  next  3  miles  eastward,  lying  in  the  northwest  part  of  Leon- 
ardsville,  the  beach  is  less  conspicuous  than  usual,  but  in  sections  8,  5,  and 
4  of  this  township  the  shore-line  is  again  distinctly  marked  by  a  slight 
terrace  in  the  till,  descending  northward  in  a  moderately  steep  slope  5  to 
10  feet,  rather  than  by  the  usual  accumulation  of  gravel.  The  top  of  this 
terrace  is  at  1,056  to  1,057  feet. 

A  few  miles  farther  north,  in  the  southeast  part  of  section  24,  Doleys- 
mount,  the  beach  is  a  low  gravel  ridge,  20  rods  wide  and  5  feet  high  above 
the  adjoining  surface,  its  crest  being  1,060  to  1,061  feet  above  the  sea. 

These  determinations  indicate  that  in  Traverse  County  the  sm-face  of 
Lake  Agassiz  during  its  maximum  stage  was  very  nearly  1,055  feet  above 
our  present  sea-level. 

In  the  northwest  corner  of  Stevens  County  this  upper  or  Herman 
beach  is  well  displayed  in  the  northwest  quarter  of  section  19,  Eldorado, 
having  an  elevation  of  about  1,063  feet.  Through  section  18  it  is  20  to  25 
rods  wide,  with  its  crest  at  1,063  to  1,066  feet,  being  a  gently  rounded 
ridge  of  sand  and  gravel,  containing  pebbles  up  to  2  or  3  inches  in  diame- 
ter. Its  height  is  7  to  10  feet  above  the  land  next  west  and  5  feet  above 
the  depression  next  east.  The  surface  on  each  side  is  till,  slowly  falling 
westward  and  rising  eastward. 

In  the  southeast  part  of  section  7  in  the  same  township  the  crest  of 
the  beach  is  at  1,067  to  1,070  feet.  Here  and  onward  the  next  2  miles, 
through  the  northwest  quarter  of  section  8,  the  southeast  part  of  section  5, 
and  the  western  and  northern  part  of  section  4,  this  formation  is  finely 
exhibited  in  a  ridge  of  gravel  and  sand  20  to  30  rods  wide,  15  feet  or  more 
above  its  base  westward,  where  lay  the  glacial  Lake  Agassiz,  and  8  to  10 
feet  above  the  depression  eastward,  which  divides  it  from  the  higher,  mod- 
erately undulating  expanse  of  till  beyond.  In  the  east  part  of  section  5. its 
elevation  is  1,065  feet,  and  through  section  4,  1,065  to  1,072  feet. 


282  THE  GLACIAL  LAKE  AGASSIZ. 

This  beach  near  the  middle  of  sectiou  15,  Logau,  Grant  County,  is 
aboiit  30  rods  wide,  with  a  broad,  nearly  flat  top,  at  1,070  feet,  having  a 
descent  of  about  15  feet  on  its  northwest  side  to  the  area  of  Lake  Agassiz 
and  half  as  much  on  the  southeast,  the  surface  thence  rising  very  gradually 
in  the  1^  miles  eastward  to  Herman.  The  beach  ridge  is  gravel,  the  land 
at  each  side  till. 

Elevations  determined  in  this  vicinity  by  the  railway  surveys  are  as 
follows:  Track  at  Herman,  1,072  feet  above  the  sea;  crest  of  the  beach 
about  1^  miles  northwest  of  Herman,  where  it  is  exit  by  the  railway,  and 
for  50  rods  southwestward,  1,064  to  1,066  feet;  depression,  40  rods  wide, 
next  soiitheast  at  the  railroad  (lowest  20  rods  from  the  top  of  the  beach), 
1,060  to  1,063  feet;  surface  of  till  at  the  southeastern  snow  fences  of  the 
railroad,  about  a  third  of  a  mile  southeast  from  the  beach,  1,073  feet;  at 
the  northwest  end  of  the  northwestern  snow  fences,  about  25  rods  north- 
west from  the  highest  part  of  the  beach,  1,054  feet;  and  at  the  original 
one  hundred  and  eightieth  mile  post,  about  a  quarter  of  a  mile  northwest 
from  the  last,  1,049  feet. 

FROM    HERMAN    NORTH    TO    THE    RED    RIVEK; 

(PLATES  XXIH   AND   XXIV.) 

Severa;l  farmhouses  are  built  on  the  top  of  the  Herman  beach  between 
6  and  10  miles  north  of  Herman.  At  Joseph  Moses's  house,  in  the  north- 
west quarter  of  section  18,  Delaware,  the  crest  of  the  beach  ridge  has  a 
height  of  1,066  to  1,067  feet,  and  the  piazza  of  the  house  is  at  1,067  feet. 
H.  D.  Kendall's  house,  at  the  east  side  of  the  southeast  quarter  of  section 
12,  Gorton,  on  the  western  slope  of  this  beach,  is  at  1,062  feet;  while  the 
top  of  the  beach  ridge,  about  25  rods  east  of  Mr.  Kendall's  house,  is  at 
1,067  feet. 

Crest  of  the  beach  through  the  next  IJ  miles  north  from  Mr.  Moses's 
house,  along  the  west  side  of  sections  18  and  7,  Delaware,  1,066  to  1,068 
feet.  The  beach  for  this  distance  is  finely  exhibited,  having  a  width  of 
about  25  rods,  rising  5  to  8  feet  above  the  depression  at  its  east  side  and 
10  to  15  feet  above  the  land  west.  L.  I.  Baker's  house  sill,  in  the  south- 
west quarter  of  section  6,  same  township,  of  same  height  with  the  top  of 
the  beach  ridge,  on  which  it  is  built,  1,068  feet. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XXIV. 


US  DIEN   a  CO   N  Y. 


MAP  OF  THE  EASTERN  SHORES  OF  LAKE  AGASSI'/  FROM  CAMPBELL  NORTH  TO  BAR!SrES\TLLE, 
COMPRISING  WFLKLV  COL'NTY,  MlNNESOTA,>\ND  PARTS  OF.VIXIOINING  COUNTIES. 

Scale  ,  6  miles  to  an  inch. 


X.£Lke  Area 


Delta 


Altitudes    of  rail i\ ay    stations    are     noted    in    fpi-t      abofc    the     sea 


THE  UPPEE  OE  HEEMAN  BEACHES.  283 

Beach  in  section  31,  Elbow  Lake,  not  so  conspicuous  as  usual,  1,066 
feet;  in  the  southwest  quarter  of  section  18,  same  township,  at  the  house 
of  Henry  Olson,  a  gracefully  rounded  low  ridge,  as  elsewhere,  composed  of 
gravel  and  sand,  including  pebbles  up  to  3  inches  in  diameter,  1,065  to 
1,066  feet;  at  Mrs.  John  S.  Ireland's,  in  the  northwest  quarter  of  the  same 
section  18,  1,070  feet;  at  Dr.  J.  M.  Tucker's,  in  the  northeast  quarter  of 
section  2,  North  Ottawa,  1,071  feet;  about  a  mile  north  of  the  last,  near 
the  north  side  of  section  35,  Lawrence,  1,075  feet;  and  about  a  mile 
farther  north,  also  1,075  feet.  Through  nearly  the  whole  of  this  distance 
it  is  a  typical  beach  ridge  of  sand  and  gravel. 

Crest  of  beach  about  30  rods  west  of  M.  L.  Adams's  house,  in  the 
northeast  quarter  of  section  26,  Lawrence,  1,075  feet,  being  4  feet  above 
the  land  adjoining  this  ridge  on  the  east  and  about  10  feet  above  the  flat 
land  near  on  the  west;  in  section  23,  same  township,  1,076  feet;  and  near 
the  south  side  of  section  10,  same  township,  1,069  to  1,074  feet. 

Extensive  sloughs  or  marshes  occur  in  section  36  and  in  sections  25 
and  24,  Lawrence,  each  being  about  a  mile  long,  lying  on  the  east  side  of 
the  beach  ridge  at  Dr.  Tucker's  and  reaching  2^  miles  northward;  the 
elevation  of  these  above  sea-level  is  about  1,060  feet. 

In  the  north  part  of  section  10  and  the  south  part  of  section  3,  Law- 
rence, this  shore-line  of  Lake  Agassiz  is  not  marked  as  usual  by  a  gravel 
ridge,  but  by  a  somewhat  abrupt  ascent  or  terrace  in  the  drift  sheet  of  till, 
the  elevation  of  the  top  of  which,  composed  partly  of  gravel,  is  1,085  to 
1,079  feet;  base  of  this  ten-ace  and  land  westward,  consisting  of  till, 
slightly  modified  on  the  area  of  Lake  Agassiz,  1,060  to  1,050  feet.  This 
escarpment,  the  eroded  shore-line  of  the  lake,  passes  about  40  rods  west  of 
N.  S.  Denton's  house,  at  the  north  side  of  section  10. 

Beach  in  section  34,  Western,  the  most  southwest  township  of  Otter- 
tail  County,  near  John  F.  Wentworth's,  1,070  to  1,075  feet;  surface  at 
Mr.  Wentworth's  barn,  1,072  feet.  Beach  25  rods  east  of  Albert  Cope- 
land's  house,  in  the  southwest  quarter  of  section  28,  Western,  1,070  to 
1,066  feet ;  where  it  is  crossed  by  the  old  road  from  Fergus  Falls  to  Camp- 
bell, near  the  northwest  corner  of  this  section  28,  1,072  feet;  through  the 
next  2  miles  iK)rth,  finely  developed,  with  nearly  constant  height,  1,072 


284  THifi  GLACIAL  LAKE  AGASSIZ. 

feet,  being  7  to  10  feet  above  the  depression  at  its  east  side  and  20  feet 
above  the  area  westward,  which  was  covered  by  Lake  Agassiz ;  at  Michael 
J.  Shortell's,  section  9,  same  township,  1,073  feet;  1  mile  farther  north, 
1,078  feet;  and  at  A.  J.  Swift's,  in  the  northwest  quarter  of  section  4,  1,076 
feet.  The  beach  at  Mr.  Swift's  and  for  half  a  mile  farther  north  is  well 
exhibited,  and,  as  in  many  other  places,  is  bordered  on  its  east  side  by  a 
narrow  strij)  of  marsh. 

Beach  in  the  northeast  quarter  of  section  33,  township  132,  range  44, 

1.076  feet ;  top  of  large  aboriginal  mound,  situated  on  the  beach  here,  1,082 
feet ;  land  30  rods  west,  1,060  feet ;  lakelet  250  feet  in  diameter,  about  an 
eighth  of  a  mile  northeast  from  the  large  mound,  1,051  feet. 

Red  River  of  the  North,  near  the  northeast  comer  of  section  33,  town- 
ship 132,  range  44,  1,014  feet ;  on  the  line  between  this  township  and  Buse, 
1,041  feet;  and  at  Dayton  bridge,  in  the  southwest  quarter  of  section  20, 
Buse,  1,064  feet,  being  8  feet  below  the  bridge.  S.  A.  Austin's  house 
foundation  in  the  southwest  quarter  of  section  29,  Buse,  1,147  feet.  Old 
grade  for  railroad  at  Dayton  bridge,  about  1,102  feet. 

No  noticeable  delta  was  brought  into  Lake  Agassiz  by  the  Red  River. 

FROM    THE    RED    RIVER    NORTH    TO    MUSKODA. 

(PLATES   XXIV   AND   XXV.) 

Crest  of  beach  near  the  south  side  of  section  21,  township  132,  range 
44,  1,077  feet;  in  this  section  21,  an  eighth  of  a  mile  north  of  the  road 
from  Fergus  Falls  to  Breckenridge,  1,079  feet;  and  for  the  next  mile  north, 

1.077  to  1,080  feet.  This  is  a  typical  beach  ridge,  gently  rounded,  com- 
posed of  sand  and  gravel,  containing  pebbles  up  to  3  inches  in  diameter; 
its  width  is  30  to  40  rods,  and  its  height  above  the  very  flat  area  on  its  Avest 
side,  which  was  covered  by  Lake  Agassiz  (usually  somewhat  marshy  next 
to  the  beach),  is  about  16  feet.  On  the  east  there  is  first  a  depression  of  4 
to  6  feet,  succeeded  within  a  fourth  of  a  mile  eastward  by  a  gentle  ascent, 
which  rises  5  to  10  or  15  feet  above  the  beach.  The  material  on  each  side 
of  the  beach  is  till,  slightly  modified  by  the  lake  on  the  west.  It  is  all 
fertile  prairie,  beautifully  green,  or  in  many  places  yellow  or  pm-ple  with 
flowers  during  July  and  August,  the  months  in  which  this  survey  was 


THE  UPPBE  OR  HEEMAN  BEACHES.  285 

made.  In  August,  1881,  no  liouses  had  been  built  on  this  beach,  nor 
within  1  mile  from  it,  along  its  first  11  miles  north  from  the  Red  River,  the 
first  house  found  near  the  beach  being  in  section  26,  Akron,  in  Wilkin 
County. 

Beach  at  a  low  portion,  probably  in  the  southeast  quarter  of  section  5, 
township  132,  range  44,  1,075  feet.  A  lake  nearly  a  mile  long  lies  on  the 
flat  lowland  about  IJ  miles  west  from  this  low  part  of  the  beach.  The 
elevation  of  this  lake  was  estimated  at  1,055  or  1,050  feet;  it  is  only  a  few 
feet  lower  than  the  general  surface  around  it.  Beach,  probably  near  the 
north  side  of  this  section  5,  1,078  feet  On  its  east  side  here  and  for  a  half 
mile  both  to  the  south  and  north  is  a  slough,  partly  filled  with  good  grass 
and  partly  with  rushes;  its  width  is  about  a  quarter  of  a  mile,  and  its 
elevation  about  1,070  feet.  The  land  west  of  the  beach  descends,  within 
1  or  2  miles,  from  1,060  to  1,050  feet. 

Beach  at  its  lowest  portion  for  this  vicinit}^,  about  a  half  mile  north  of 
the  preceding  and  near  the  center  of  section  32,  Carlisle,  1,070  to  1,068 
feet,  being  only  2  feet  above  the  marsh  or  slough  on  its  east  side.  A  rail- 
road gi'ade,  abandoned,  lies  a  third  of  a  mile  east  of  this.  Beach  a  fourth 
of  a  mile  farther  north,  1,077  feet,  and,  about  1  mile  north  from  its  lowest 
portion,  1,075  feet,  cut  by  a  ravine,  the  bottom  of  which  is  nearly  at 
1,063  feet.  This  ravine  is  some  30  rods  west  of  the  abandoned  railroad 
embankment. 

Railroad  grade  where  it  crosses  the  beach,  about  a  mile  northwesterly 
from  the  ravine  mentioned,  1,077  feet.  Beach  here,  1,076  feet,  being  8  to 
10  feet  above  the  slough  on  its  east  side,  and  having  about  the  same  height 
above  the  mareh  next  to  it  westward.  The  material  of  the  beach,  shown 
by  the  railroad  embankment,  which  is  made  of  it  along  a  distance  of  a  third 
of  a  mile,  is  coarse  gravel,  with  abundant  pebbles  of  all  sizes  up  to  6  inches 
in  diameter,  fully  half  of  them  being  limestone. 

Crest  of  beach  in  the  south  half  of  section  23,  Akron,  1,079  to  1,080 
feet;  in  the  northwest  quarter  of  this  section  23,  1,075  to  1,080  feet. 
Through  sections  14,  10,  and  3,  Akron,  the  beach  does  not  have  its  ordi- 
nary ridged  form,  but  is  mostly  marked  by  a  deposit  of  gravel  and  sand 
lying  upon  a  slope  that  rises  gradually  eastward.      Its  elevation  here  is 


286  THE  GLACIAL  LAKE  AGASSIZ. 

1,075  to  1,085  feet.  In  the  southern  part  of  this  distance,  probably  in  the 
southwest  quarter  of  section  14,  the  margin  of  the  flat,  somewhat  marshy 
area  that  appears  to  have  been  covered  by  Lake  Agassiz  is  very  definite  at 
1,075  feet,  which  thus  was  probably  the  height  of  the  lake  here. 

Beach  in  the  southwest  quarter  of  section  34,  Tanberg,  composed  of 
gravel,  nearly  flat,  25  to  30  rods  wide,  1,084  to  1,087  feet,  bordered  by  a 
depression  of  2  to  5  feet  on  the  east  and  by  an  expanse  10  to  15  feet  lower 
on  the  west.  Beach  in  the  northwest  quarter  of  this  section  34,  also  1,084 
to*  1,08  7  feet.  Here  the  land  next  east  does  not  present  the  usual  slight 
hollow  dividing  the  beach  ridge  from  the  higher  land  eastward;  instead  is 
a  springy  belt,  mostly  1,089  feet,  quite  marshy,  yet  slowly  rising  2  to  4 
feet  above  the  belt  of  beach  gravel.  Occasional  hummocks,  about  2  feet 
above  the  general  surface  and  covered  with  rank  grass  about  6  feet  high, 
form  part  of  this  belt  of  marsh  and  shaking  bog.  Next  to  the  east  is  a 
slough  about  1,086  feet,  or  3  feet  below  the  springy  tract,  and  this  is  suc- 
ceeded by  a  surface  of  moderately  undulating  till,  which  rises  gradually 
eastward. 

Sloughs,  mostly  filled  with  rushes  and  having  areas  of  water  all  the 
year,  occupy  a  width  of  1  to  2  miles  next  west  of  the  shore-line  and  beach 
of  Lake  Agassiz  and  extend  nearly  continuously  10  miles  from  south  to 
north,  from  the  middle  of  Akron  to  the  south  edge  of  Prairie  View  Town- 
ship. The  elevation  of  this  belt  of  sloughs  is  1,080  to  1,050  feet,  being 
considerably  lower  on  its  west  than  on  its  east  border.  The  liighest  land 
westward  in  the  west  part  of  Tanberg,  between  these  marshes  and  Manstou, 
is  about  1,060  feet.  Along  most  of  this  distance  the  ordinary  beach  ridge 
is  wanting. 

Great  Northern  Railway  track  at  Lawndale  water  tank,  1,089  feet. 
Here  a  side-track  has  been  laid,  extending  about  a  third  of  a  mile  north- 
ward, with  its  northern  end  some  50  rods  east  of  the  main  line,  to  take 
ballast  from  the  beach,  which  is  well  exhibited  here  and  onward,  having  its 
typical  ridged  form.  The  elevation  of  its  crest  is  1,091  to  1,094  feet.  It 
is  composed  of  gravel  and  sand  in  about  equal  amounts,  interstratified 
mainly  in  level  layers,  but  with  these  often  obliquely  laminated.  Most  of 
the  gravel  is  quite  fine,  and  the  coarsest  gravel  foimd  here  has  pebbles  only 
2  to  3  inches  in  diameter.     About  half  of  it  is  limestone. 


THE  UPPER  OR  HERMAN  BEACHES.  287 

Beach  ridge  1  mile  farther  north,  1,094  feet;  three-fourths  of  a  mile 
north  of  the  last  and  close  south  of  a  ravine,  1,099  feet.  Beach  about  3 
miles  north  from  Lawndale  water  tank,  probably  in  the  south  part  of  section 
16,  Prairie  View,  not  ridged,  but  a  belt  25  rods  wide,  of  gravel  and  sand, 
on  a  slope  of  till  that  rises  eastward,  1,080  to  1,102  feet.  Beach,  a  ridge  of 
gravel  and  sand,  a  third  of  a  mile  north  from  the  last,  1,105  feet.  The 
beach  in  section  9  of  this  township  is  spread  more  broadly  than  usual,  its 
higher  parts  being  1,095  to  1,107  feet.  Here  the  beach  deposits  are  crossed 
obliquely  by  several  broad  depressions  10  to  15  feet  deep,  running  south- 
southwest.  The  depression  east  of  all  these  banks  of  gravel  and  sand  is 
about  1,090  feet  above  the  sea. 

Entering  Clay  County,  the  elevation  of  this  upper  or  Herman  beach 
at- the  east  side  of  section  33,  Humboldt,  is  1,100  feet  above  the  sea.  The 
land  thence  for  two-thirds  of  a  mile  east  is  low  and  smooth,  not  higher  than 
the  beach.  Beyond  this  the  next  third  of  a  mile  northeastward,  in  the 
north  part  of  section  34,  is  very  rocky,  with  many  bowlders  up  to  6  and 
rai-ely  10  feet  in  diameter,  the  contour  being  moderately  rolling  10  to  30 
or  40  feet  above  the  beach.  Farther  eastward  here  and  through  the  next 
15  miles  north  to  the  Northern  Pacific  Railroad,  the  moderately  rolling  or 
smoothly  hilly  till  rises  100  to  250  feet  above  this  beach  within  the  distance 
of  about  10  miles  between  it  and  the  east  line  of  the  county. 

Elevation  of  the  crest  of  the  beach  ridge  in  the  east  half  of  section  28, 
Humboldt,  one-fourth  to  three-fourths  of  a  mile  south  of  Willow  River, 
1,098  to  1,100  feet  In  the  3  miles  westward  to  Barnesville  the  area  that 
was  covered  by  Lake  Agassiz  shows  here  and  there  bowlders  projecting  1 
to  2  feet  above  the  surface,  which  is  till,  slightly  smoothed  by  the  lake. 

Great  Northern  Railway  track  at  Barnesville,  1,020  feet. 

The  beach  for  three-fourths  of  a  mile  north  from  Willow  River  consists 
of  a  belt  of  gravel  and  sand,  lying  on  an  eastwardly  ascending  slope  of  till. 
Through  the  next  1^  miles  northward,  in  the  northwest  quarter  of  section 
22  and  in  section  15,  Humboldt,  the  shore  of  Lake  Agassiz  is  not  marked 
by  the  usual  beach  of  gravel  and  sand,  but  instead  becomes  a  belt  of 
marshy  and  springy  land  20  to  50  rods  wide,  rising  by  a  gentle  slope  east- 
ward, rough  with  many  hummocks  and  hollows,  in  some  portions  forming 
a  quaking  bog,  in  which  horses  and  oxen  attempting  to  cross  are  mired. 


288  THE  GLACIAL  LAKE  AGASSIZ. 

In  the  next  2  miles  northwand,  through  sections  10  and  3,  Humboldt, 
the  beach  is  nowhere  well  marked  as  a  ridge,  but  is  mainly  a  belt  of  gravel 
and  sand,  lying  on  a  slope  of  till,  which  gradually  rises  30  or  40  feet  higher 
at  the  east.  The  lack  of  typical  beach  deposits  on  this  shore  through  the 
north  half  of  this  township  is  probably  due  to  its  sheltered  situation  in 
the  lee  of  islands  on  the  northwest.  The  coiu'se  of  the  shore  currents, 
determined  by  the  prevailing  winds,  seems  to  have  been  southward,  as  on 
the  shores  of  Lake  Michigan. 

Highest  part  of  southern  island  in  the  east  edge  of  Lake  Agassiz,  in 
the  northeast  quarter  of  section  5,  Humboldt,  extending  northward  into 
Skree,  1,117  to  1,122  feet.  This  island  was  about  1  mile  long  from  south 
to  north.  Crest  of  beach  on  its  west  side,  a  well-developed  ridge  of  gi-avel 
near  the  middle  of  the  north  line  of  section  5,  1,095  feet;  and  for  a  third  of  a 
mile  north-northwest  from  this,  1,094  to  1,096  feet.  On  the  east  side  of 
the  beach,  as  it  continues  northward,  is  a  slough  two-thirds  of  a  mile  long 
from  south  to  north  and  about  30  rods  wide,  1,085  feet.  This  was  evidently 
filled  by  a  lagoon,  sheltered  on  the  southeast  by  the  island  and  separated 
from  the  main  lake  by  the  beach.  Toward  the  northeast  it  widened  into  a 
shallow  expanse  of  water  8  to  15  feet  deep,  about  IJ  miles  wide,  divided 
from  the  broad  lake  on  the.  west  by  two  islands  and  this  beach  or  bar  which 
connected  them.  Lake  Agassiz  here  appears  to  have  stood  at  the  height  of 
1,090  to  1,095  feet. 

Top  of  the  beach  or  bar  in  the  north  part  of  section  32,  Skree,  a  broad 
rounded  ridge  of  gravel,  with  pebbles  up  to  3  or  4  inches  in  diameter,  1,103 
feet,  and  through  the  next  half  mile,  in  the  south  half  of  section  29,  1,102 
to  1,104  feet.  Along  part  of  this  distance  the  beach  ndge  is  bounded  east- 
ward by  a  steeper  descent  than  usual,  the  land  next  east  being  1,085  to 
1,090  feet  above  the  sea.  This  beach  or  bar  continues  northward  in  a 
typical  ridge  through  sections  29  and  20,  same  township. 

Beach  or  bar  at  L.  Williams's  house,  in  the  southeast  quarter  of  section 
20,  Skree,  1,101  feet;  a  quarter  of  a  mile  farther  north,  1,106  feet;  three- 
quarters  of  a  mile  north  of  Mr.  Williams's,  near  the  middle  of  the  north 
line  of  section  20,  1,110  feet,  continuing  a  very  definite  ridge  thi-ough  the 
south  half  of  section  17,  1,109  to  1,110  feet. 


ISLANDS  NORTHEAST  OF  BAENESVILLE.  289 

Near  the  middle  of"  this  section  17  the  beach  deposit  of  gravel  aud 
saud  ceases  at  the  west  side  of  the  northern  island,  which  was  situated  in 
the  east  half  of  this  section  and  extended  also  eastward  in  a  long,  low  pro- 
jection nearly  across  the  south  side  of  section  16,  aud  northward  half  way 
across  section  8.  Highest  part  of  this  island,  in  or  near  the  northeast 
quarter  of  the  northwest  quarter  of  section  17,  about  1,125  feet.  The  old 
shore  of  the  north  half  of  this  island  has  no  beach  ridge  nor  other  deposits 
of  gravel  and  sand,  but  is  plentifully  strewn  with  large  bowlders  up  to  5 
and  10  feet  in  diameter,  and  many  of  these  project  2  to  5  feet  above  the 
general  surface.  The  lake  waves  eroded  here,  and  deposited  the  sand  and 
gravel  gathered  from  this  till  as  a  beach  a  little  farther  south. 

North  and  northeast  from  this  northern  island  a  lower  expanse,  nearly 
level  and  in  some  portions  marshy,  resembling  the  broad,  flat  valley  of  the 
Red  River,  extends  IJ  miles  to  the  east  shore  of  Lake  Agassiz,  its  height 
being  1,075  to  1,090  feet,  or  10  to  25  feet  below  the  surface  of  the  ancient 
lake.  The  distance  between  these  islarids  was  2  miles,  and  the  distance 
from  the  summit  of  the  first  to  that  of  the  second,  nearly  due  north,  4  miles. 
Each  of  them  rose  about  25  feet  above  Lake  Agassiz.  The  strait  between 
them  and  the  mainland  eastward  was  10  to  20  feet  deep  and  from  1  to  IJ 
miles  wide,  excepting  a  narrow  place  near  the  southeast  corner  of  section 
16.  East  of  the  northern  island  the  main  shore  of  the  lake  was  indented  by 
a  bay  a  third  to  a  lialf  of  a  mile  wide  and  about  10  feet  deep,  stretching  2  J 
miles  southeastward  from  the  lakelet  at  the  northwest  comer  of  section  10 
to  the  west  part  of  section  23,  Skree.  The  shore  of  the  lake  east  of  its 
islands  along  this  bay  and  northwesterly  to  the  north  line  of  this  township 
lacks  the  beach  deposits  which  elsewhere  distinguish  it. 

In  its.  continuation  northwestward  the  shore-line  of  the  old  lake  runs 
diagonally  across  section  32,  Hawley,  where  it  again  presents  the  anoma- 
lous character  of  a  very  "springy  and  marshy  belt,  20  to  40  rods  wide,  rough 
with  hummocks  and  in  many  places  so  deeply  miry  that  it  is  dangerous  for 
teams.  This  boggy  tract  has  a  gentle  descent  westward,  its  lower  portion 
being  about  1,085  feet,  and  its  upper  border,  very  nearly  level  across  this 
entire  section,  being  1,098  to  1,100  feet,  which  Avas  almost  exactly  the  height 
of  Lake  Agassiz,  as  shown  by  its  distinct  beach  of  gravel  and  sand  at  the 
MON  XXV 19 


290  THE  GLACIAL  LAKE  AGASSIZ. 

south  ana  north.  Next  eastward  rises  a  moderately  undtilatiug  slope  of  till, 
strewn  with  abundant  bowlders;  and  rarely  a  bowlder  2  to  5  feet  in  diam- 
eter is  seen  on  the  springy  land  that  marks  the  border  of  the  ancient  lake. 

DELTA    OF    THE    BUFFALO    RIVEK. 

(PLATE  XXV.) 

The  delta  brought  into  the  east  side  of  Lake  Agassiz  by  tlie  Buffalo 
River  extends  about  5  miles  southwestward  from  Muskoda,  forming  a  con- 
tinuously descending  plain  of  stratified  sand  and  fine  gravel,  declining  from 
1,100  feet  near  Muskoda  to  1,073  feet  at  its  southwestern  limit  in  the  north 
part  of  section  34,  Riverton.  Here  and  northward  along-  a  distance  of  3 
miles  to  the  Bufi"alo  River  this  delta  plain  is  terminated  by  a  steep  slope, 
25  to  40  feet  high,  like  the  face  of  a  terrace.  The  outer  poi-tion  of  the 
original  delta,  beyond  this  line,  has  been  carried  away  by  the  waves  and 
shore  cuiTents  of  the  lake  when  it  stood  at  the  lower  levels  marked  by  the 
iNorcross  and  Tintali  beaches,  as  shown  in  fig.  11. 


lOOO 


Fig.  11. — Section  across  the  delta  of  the  Bufialo  Iliver.     Horizoutal  scale,  one-hall'  uiile  to  an  inch. 

Northern  Pacific  Railroad  track  at  Muskoda,  1,090  feet.  Thi-eshold 
of  church  a  quarter  of  a  mile  southeast  from  Muskoda  depot,  1,113  feet. 
Beach  here  and  for  a  third  of  a  mile  south  to  the  Buff"alo  River,  as  also  at 
the  excavation  for  the  railroad,  25  rods  north  of  the  church,  nearly  uniform 
elevation  of  its  crest,  1,113  to  1,114  feet.  The  beach  is  35  rods  wide,  rising 
14  or  15  feet  in  a  gentle  swell  above  the  edge  of  the  delta  of  modified  drift 
on  the  west  and  descending  the  same  amount  to  the  depression  at  its  east 
side.  It  is  made  up  of  interstratified  gravel  and  sand,  the  former  prevail- 
ing, including  pebbles  iip  to  3  or  4  inches  and  rarely  6  or  even  9  inches  in 
diameter,  all  waterworn.  Half  or  two-thirds  of  these  pebl^les  and  cobbles 
are  limestone.  No  bowlders  occur  here,  nor  are  they  found  in  any  of  the 
beach  deposits  of  Lake  Agassiz. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.   XXV 


L1US  StEN  a  CO  NY 


MAP      F  THE  Ei\STERN  BEACHES  AND  DELTAS  OF  LAKE  AGASSIZ  PROM  MrSKODA 
NORTH  THROTHIH  CIvWAND  NORMAN  COUNTIES, MINNESOTA.TO  THE  SAND  HH.I-  RIVKH. 

Scale, 6  miles  loan  inch. 


Ijake  Area 


Dell; 


Altitudes     of   TtaHwny  statioixs    are    riofed    in    fi-ri    ti/>,>\i-  f/ic    .-ieti 


THE  BUFFALO  DELTA.  291 

The  area  of  the  Buffah>  deha  extends  7  miles  from  north  to  south,  with 
a  width  of  2  to  3|  miles  Its  average  thickness  is  probably  about  50  feet, 
and  its  volume  is  therefore  approximately  one-sixth  of  a  cubic  mile.  It 
would  make  a'  very  sightly  hill  if  its  material  were  piled  on  the  flat  plain 
of  the  Red  River  Valley,  for  it  would  cover  a  circle  2  miles  in  diameter  and 
rise  to  a  peak  about  900  feet  high.  Lying  on  the  slope  which  rises  east  from 
this  valley,  however,  and  being  spread  over  a  considerable  area  with  com- 
paratively little  thickness,  its  mass  does  not  especially  command  attention 
until  investigation  reveals  that  it  came  almost  wholly  from  drift  that  was 
contained  within  the  ice-sheet,  being  deposited  here  by  the  streams  from 
its  melting. 

The  existence  of  well-defined  and  conspicuous  delta  deposits  having 
the  altitude  of  the  Herman  beach,  where  the  Buffalo  and  Sand  Hill  rivers 
enter  the  east  side  of  the  area  of  Lake  Agassiz,  while  no  such  deposits  are 
found  where  other  streams  of  equal  or  larger  size  enter  this  area,  as  the 
Red  River,  the  Wild  Rice,  and  the  Red  Lake  River,  seems  explicable  only 
by  the  derivation  of  the  gravel  and  sand  forming  these  deltas  mostly  from 
the  englacial  drift  of  the  melting  ice-sheet  upon  the  adjacent  area  at  the 
east.  Comparatively  small  tribute  was  brought  into  this  glacial  lake  from 
the  erosion  of  the  stream  valleys  after  their  areas  became  uncovered 
from  the  ice,  excepting  where  it  received  the  very  large  rivers  flowing  from 
other  glacial  lakes  at  the  west.  Here  and  there,  because  of  irregularities 
in  the  outline  of  the  ice-sheet,  by  which  the  drainage  of  its  surface  was 
poured  down  upon  certain  limited  tracts  and  was  discharged  thence  along 
the  courses  of  now  existing  streams,  as  the  Buffalo  and  Sand  Hill  rivers, 
and  because  the  retreat  of  the  ice  was  now  rapid  and  anon  was  inteiTupted 
by  halt  or  readvance,  with  the  accumulation  of  moraines,  much  of  the 
material  which  had  been  inclosed  within  the  basal  part  of  the  ice-mass 
seems  to  have  been  washed  away  by  its  streams  and  earned  into  Lake 
Agassiz  to  form  deltas. 

When  such  glacial  streams  encountered  no  lake  to  receive  their  tribute, 
and  flowed  far  before  reaching  the  sea,  the  gravel,  sand,  and  fine  silt  or  clay 
which  they  brought  were  spread  by  the  rivers  along  their  courses  as  plains 
of  modified  drift.     In  some  instances,  since  the  ice -sheet  disappeared  and 


292  THE  GLACIAL  LAKE  AGASSIZ. 

the  draiuage  from  it  ceased,  these  plains  are  left  far  from  any  important 
stream.  Similarly,  on  the  west  side  of  Lake  Agassiz,  a  large  delta  extending 
southward  from  the  Elk  Valley  was  deposited  by  a  proportionally  large 
river  flowing  from  the  ice-sheet,  but  no  considerable  river  now  enters  the 
lake  area  there. 

Opposite  to  the  Buffalo  delta,  within  a  distance  of  about  30  miles  to 
the  east,  the  ice  front  was  indented  by  a  great  embayment  or  reentrant 
angle  at  the  time  of  formation  of  the  eighth  or  Fergus  Falls  moraine. 
While  the  ice  border  was  receding  from  the  seventh  or  Dovre  to  the  Fergus 
Falls  moraine,  the  conditions  of  its  melting  were  probably  unfavorable  for 
the  formation  of  deltas  in  this  glacial  lake;  but  during  the  accumulation 
of  the  Fergus  Falls  moraine  the  drainage  from  the  ice  border  converged 
toward  the  Buffalo  River  and  caused  its  delta  to  be  formed.  Again,  when 
the  ice-sheet  had  retreated  another  stage  and  was  forming  its  ninth  or  Leaf 
Hills  moraine,  this  indentation  of  the  ice  front,  having  fallen  back  about 
40  miles  northward  from  its  former  position,  sent  its  glacial  streams  to  the 
Sand  Hill  River,  and  a  second  delta  was  brought  into  the  lake. 

In  the  same  manner,  the  much  larger  Sheyenne,  Elk  Valley,  Pembina, 
and  Assiniboine  deltas,  brought  into  Lake  Agassiz  from  the  west  and  hav- 
ing likewise  the  height  of  the  early  Herman  beaches,  are  referable  chiefly 
to  the  drainage  from  the  melting  ice-sheet,  and  in  less  measure  to  erosion 
of  the  river  valleys.  The  material  of  all  the  deltas  of  this  lake  is  princi- 
pally modified  drift,  rather  than  alluvium  like  that  which  the  streams  now 
transport  and  spread  over  their  bottom-lands  at  every  stage  of  flood. 

FROM   MUSKODA   NORTH    TO    THE    SAND    HILL   RIVER. 

(plate   XXV.) 

In  the  next  2  miles  north  of  Muskoda  the  crest  of  the  Herman  beach 
ridge  ranges  mainly  from  1,113  to  1,125  feet  above  the  sea;  at  its  lowest 
depression,  about  1  mile  north  of  Muskoda,  its  height  is  1,105  feet;  at 
William  Perkins's  house,  in  the  southeast  quarter  of  section  30,  Cromwell, 
1,122  feet;  an  eighth  to  a  third  of  a  mile  south-southeast  from  Mr.  Per- 
kins's, 1,130  feet.     A  nearly  or  quite  continuous  depression,  from  a  fifth  to 


THE  UPPER  OR  HERMAN  BEACHES.  293 

a  third  of  a  mile  wide,  lies  at  the  east  side  of  this  beach,  declining  in  eleva- 
tion from  1,118  feet  near  Mr.  Perkins's  house  to  1,100  feet  at  Muskoda. 
This  distance  is  about  3  miles. 

The  surface  of  Lake  Agassiz  in  its  maximum  stage  was,  at  Muskoda, 
1,105  feet,  very  approximately,  above  our  present  sea-level.  Within  5  to 
10  miles  northward  its  height  seems  to  have  been  1,110  to  1,115  feet. 

Beach  through  the  north  half  of  section  30,  Cromwell,  1,128  to  1,131 
feet,  and  through  the  west  part  of  sections  19  and  18,  same  township,  1,125 
to  1,130  feet,  composed  of  sand  and  fine  gravel,  not  generally  in  a  typical 
ridge,  but  often  with  a  depression  2  to  5  feet  lower  eastward  and  bounded 
on  the  west  by  a  descent  of  about  30  feet  within  an  eighth  of  a  luile.  A 
surface  of  slightl}^  undulating  till  rises  very  gradually  from  this  beach 
eastward. 

Herman  beach  at  a  high  portion  in  or  near  the  southeast  quarter  of 
section  1,  township  140,  range  46,  1,136  feet.  For  a  mile  next  south  from 
this  point  it  is  a  finely  rounded  ridge  of  gravel,  rising  northward  from  1,130 
to  1,136  feet.  The  depression  at  its  east  side  is  4  to  6  feet  lower;  then  the 
surface  gently  rises  at  a  quarter  to  a  third  of  a  mile  from  the  beach  to  1,135 
or  1,140  feet,  beyond  which  eastward  this  nearly  level  but  slightly  undu- 
lating expanse  of  till  rises  only  5  or  10  feet  per  mile.  Beach  a  fourth  of 
a  mile  north-northeast  from  the  high  point  mentioned,  probably  in  the 
nortliAvest  quarter  of  section  6,  Cromwell,  1,128  to  1,127  feet.  This  is  an 
ordinary  beach  ridge  of  gravel  and  sand,  with  a  depression  of  2  or  3  feet 
next  east. 

Near  the  south  line  of  section  29,  Keene,  both  the  Herman  and  Nor- 
cross  beaches,  here  about  two-thirds  of  a  mile  apart,  are  intersected  by  a 
watercourse.  At  its  north  side  the  upper  or  Herman  beach,  near  the  east 
line  of  section  29  and  in  the  northwest  quarter  of  section  28,  consists  of 
two  well-marked  ridges  of  gravel  and  sand,  some  30  rods  apart  and  about 
10  feet  above  the  land  eastward  and  between  them.  These  ridges  unite  in 
or  near  the  southwest  quarter  of  the  southwest  quarter  of  section  21,  at  the 
height  of  1,130  to  1,132  feet.  Beach  three- fourths  of  a  mile  farther  north, 
probablj' near  the  north  line  of  section  21,  a  typical  gravel  ridge,  1,134  feet, 
10  feet  above  the  land  next  east;  but  a  sixtli  of  a  mile  farther  northeast  this 
beach  ridge  is  depressed  to  1,123  feet. 


294  THE  GLACIAL  LAKE  AGASSIZ. 

A  lower  beach,  contemporaueous  with  the  Herman  beach  fartlier  south, 
but  foiinecl  when  the  surface  of  the  lake  in  this  latitude  had  fallen  slightly 
from  its  highest  level,  is  finely  exhibited  at  a  distance  of  one-third  to  two- 
thirds  of  a  mile  west  from  the  upper  beach,  through  the  4  miles  from  the 
south  side  of  section  20  to  the  northeast  corner  of  section  4,  Keene.  The 
elevation  of  this  secondary  beach  in  the  south  pai-t  of  section  20  is  1,115 
feet ;  thence  to  a  stream  near  the  east  line  of  the  southeast  quarter  of  sec- 
tion 17,  1,118  to  1,123  feet;  at  each  side  of  this  stream,  1,118  feet;  north- 
ward, in  the  northwest  part  of  section  16  and  in  the  southwest  quarter  of 
section  9,  1,118  to  1  121  feet;  and  in  the  north  part  of  section  9,  1,121  to 
1  127  feet. 

Upper  beach  through  the  west  part  of  section  10,  Keene,  1,130  to 
1,137  feet,  increasing  in  height  from  south  to  north.  This  is  a  typical 
beach  ridge  of  gravel,  with  a  rather  abrupt  descent  on  its  east  side  to  land 
6  or  8  feet  lower,  which  thence  ascends  with  a  slightly  undulating  sv;i'face 
eastward.  The  elevation  of  the  upper  beach  in  this  township,  1,123  to 
1,137  feet,  shows  that  the  height  of  Lake  Agassiz  here,  during  its  maxi- 
mum stage,  was  about  1,120  feet.  The  secondary  beach  was  made  by  the 
lake  after  it  had  fallen  6  to  10  feet. 

In  section  3,  Keene,  the  crest  of  the  upper  beach  is  at  1,134  to  1,137 
feet,  10  feet  above  the  land  next  east;  and  the  top  of  the  secondary  Her- 
man beach,  parallel  with  this  and  aljout  tln-ee-fotirths  of  a  mile  distant  to 
the  northwest,  in  sections  4  and  34,  is  at  1,123  to  1,127  feet,  being  thus  10 
feet  lower  than  the  highest  parts  of  the  eastei'u  beach.  Extensive  sloughs, 
inclosing  lakelets,  lie  between  these  beaches  in  sections  34  and  35,  Hagen, 
at  an  elevation  of  1,115  to  1,120  feet,  but  sinking  northward  to  1,105  feet. 
The  secondary  beach  continues  to  the  northeast  corner  of  section  26,  declin- 
ing in  height  northeastward  as  it  approaches  the  South  Branch  of  the  WUd 
Rice  River,  being  at  1,125  to  1,115  feet. 

Upper  beach  in  section  35  and  in  the  south  part  of  section  25,  Hagen, 
1,140  to  1,142  feet.  This  is  a  typical  beach  ridge  of  sand  and  gravel, 
about  30  rods  wide,  with  the  land  next  southeast  5  to  8  feet  lower,  and 
divided  from  the  secondary  beach  northwesterly  by  a  slough  about  1  mile 
wide,  this  slough  being  at  1,115  to  1,105  feet. 


THE  UPPER  OE  HERMAN  BEACHES.  295 

Crest  of  beach  at  B.  O.  Helde's  house,  in  the  south  half  of  the  south- 
west quarter  of  section  30,  Ulen,  1,138  feet.  The  flat  expan.se  of  the  Red 
River  Valley  reaches  east  on  the  South  Branch  of  the  Wild  Rice  River  to 
section  16,  Hagen,  probably  being  there  about  975  feet  above  the  sea,  or 
160  feet  below  this  upper  beach  of  Lake  Agassiz,  4  or  5  miles  southeast. 

Beach  through  sections  30  and  29,  Ulen,  extending  1^  miles  east- 
northeast  from  Mr.  Helde's  to  the  South  Branch  of  the  Wild  Rice  River, 
in  a  loAV,  gently  rounded  ridge  of  gravel,  30  rods  wide,  5  to  8  feet  above 
the  area  of  till  next  southeast  and  about  15  feet  above  the  surface  close  at 
its  northwest  side,  1,138  to  1,142,  mostly  1,140  feet. 

South  Branch  of  Wild  Rice  River,  in  the  southwest  quarter  of  section 
21,  Ulen,  1,095  feet.  The  beach  is  developed  as  a  typical  gravel  ridge,  in 
or  near  the  west  half  of  section  16,  Ulen,  a  half  mile  to  IJ  miles  north  of 
the  South  Branch,  with  its  crest  at  1,140  to  1,143  feet;  surface  of  till  an 
eighth  to  a  quai-ter  of  a  mile  next  east,  1,135  feet.  Farther  east  the  slightly 
or  moderately  undulating  expanse  of  till  has  an  average  ascent  of  about  10 
feet  a  mile  for  15  miles  to  the  base  of  the  high  land  at  the  White  Earth 
Agency,  which  is  dimly  visible,  blue,  close  to  the  horizon.  Westward  the 
surface  gradually  descends  to  the  Norcross  beach,  nearly  60  feet  lower, 
which  is  the  farthest  land  in  sight  in  that  direction,  about  3  miles  distant, 
beyond  which  lies  the  flat  Red  River  Valley. 

Entering  Norman  County,  an  unusually  high  portion  of  the  Herman 
beach  is  found  in  or  near  the  southeast  quarter  of  the  southeast  quarter 
of  section  33,  Home  Lake,  having  its  crest  at  1,149  feet.  It  holds  this 
elevation  for  an  extent  of  some  20  rods,  on  each  side  of  which  its  height  is 
mostly  from  1,139  to  1,145  feet.  Its  material  is  coarse  gravel,  principally 
limestone,  with  pebbles  and  cobbles  up  to  4  and  6  inches  in  diameter. 
Surface  close  east  of  this  beach,  1,137  feet.  A  slight  swell  above  the  gen- 
eral descending  slope  westward,  about  2  miles  distant,  has  a  height  very 
nearly  1,125  feet.  This  maybe  the  continuation  of  the  secondary  beach 
that  was  seen  in  Keene  Township.  It  hides  the  view  farther  west,  except 
from  the  highest  point  of  the  beach  (1,149  feet),  where  the  distant  belts  of 
timber  along  the  Red  and  Wild  Rice  rivers  are  visible. 

Beach  at  J.  T.  Huseby's  house,  in  the  northwest  quarter  of  section  26, 
Home  Lake,  1,147  feet;  tlu-ough  1^  miles  next  north,  in  the  northwest 


296  THE  GLACIAL  LAKE  AGASSIZ. 

quarter  of  section  26  and  the  west  part  of  section  23,  forming  a  broad,  low 
ridge  of  gravel  and  sand,  1,145  to  1,149  feet.  In  or  near  sections  17  and 
16,  Flom,  a  prominent,  massive  hill,  called  "Frenchman's  Bluff,"  of  some- 
what irregular  form,  composed  of  moi'ainic  till,  rises  150  feet  or  more  above 
tliis  beach. 

Through  the  west  part  of  the  noi'thwest  quarter  of  section  14,  Home 
Lake,  the  beach  is  mostly  a  typical  gravel  ridge,  with  its  crest  at  1,147  to 
1,152  feet.  In  the  northwest  quarter  of  section  11,  same  township,  it 
curves  northeastward  and  attains  an  unusually  massive  development,  its 
crest  being  at  1,150  to  1,158  feet,  rising  15  feet  above  the  land  next  south- 
east and  25  or  30  feet  above  the  border  of  the  area  of  Lake  Agassiz  at  its 
northwest  side. 

Crest  of  beach,  a  well-marked  gravel  ridge,  near  the  southwest  corner 
of  section  1,  Home  Lake,  1,156  feet,  and  an  eighth  of  a  mile  east-northeast 
from  this,  1,150  feet.  J.  G.  Aurdal's  house,  foundation,  in  the  northeast 
quarter  of  section  6,  Flom,  1,148  feet.  This  is  situated  on  the  beach, 
which  here  is  a  deposit  of  gravel  and  sand  8  feet  or  more  in  depth,  lying 
upon  a  slope  of  till  that  ascends  southeastward.  Anton  Johnson's  store, 
foundation,  on  this  beach,  in  the  southeast  quarter  of  section  31,  Fosum, 
1,142  feet.  Creek  flowing  northwesterly  between  the  last  two,  about  1,105 
feet.  Wild  Rice  River,  2  miles  north  of  Johnson's  store,  approximately 
1,050  feet. 

Secondary  Herman  beach,  a  well-marked,  broad,  smoothly  rounded 
gravel  ridge,  extending  from  southwest  to  northeast,  crossed  by  the  town- 
ship line  road  at  the  north  side  of  the  noi'theast  quarter  of  the  northwest 
quarter  of  section  2,  Home  Lake,  1,137  feet.  It  is  about  30  rods  wide, 
and  rises  5  to  10  feet  above  the  depression  at  its  southeast  side. 

A  broad  belt  of  timber  borders  the  Wild  Rice  River,  lying  mostly  on 
its  north  side,  in  Fosum  and  Wild  Rice  townships,  and  at  the  time  of  this 
survey,  in  1881,  no  road  or  bridge  afforded  a  crossing  here.  Therefore 
this  series  of  levels  was  resumed  north  of  the  Wild  Rice  River  by  starting 
from  Rolette  station  of  the  St.  Paul,  Minneapolis  and  Manitoba  (now  the 
Great  Northern)  Railway,  892  feet  above  the  sea,  near  the  middle  of  sec- 
tion 17,  Lockhart,  about  1.^  miles  north  of  the  Lockhart  farm.     Proceeding 


THE  UPPER  OR  HERMAK  BEACHES.  297 

eastward  from  this  point,  the  first  observations  of  the  upper  beach  were  in 
Waukon,  Siindal,  and  Garfield  townships. 

This  beacli  is  intersected  by  the  Wild  Rice  River  near  the  middle  of 
Fosum,  and  thence  it  passes  north-northwesterly  through  the  west  part  of 
Waukon.  In  sections  7  and  6,  Waukon,  it  is  a  low,  smooth  ridge  of  gravel 
and  sand  about  25  rods  wide,  rising  5  to  10  feet.  In  the  west  half  of  this 
section  6  and  in  section  36,  Sundal,  the  old  Pembina  trail  lies  on  it. 

About  2  miles  west  of  the  upj)er  beacli,  a  secondary  Herman  beach,  of 
similar  material  and  contour,  probably  20  feet  lower,  was  observed  a  few 
rods  east  of  the  stake  at  the  middle  of  the  north  side  of  section  14,  Strand, 
having  a  height  of  (3  to  8  feet  above  its  base,  with  a  smaller  ridge  of  sand 
and  gravel,  3  feet  high  above  its  base,  close  west  of  this  stake.  Again,  a 
half  mile  farther  west,  in  the  northeast  corner  of  section  15,  Strand,  another 
Herman  beacli,  probably  10  feet  below  the  last,  was  noted,  having  a  height 
of  4  or  5  feet  above  its  base. 

Traveling  northwestward  along  the  Pembina  trail,  the  tipper  beach 
ridge  was  not  distinctly  observed  after  leaving  section  36,  Sundal,  imtil  it 
is  again  occupied  .by  the  trail  in  section  9  of  this  township.  The  interven- 
ing 3  miles  are  flat  and  nearly  level.  Probably  the  beach,  less  noticeable 
than  usual,  lies  within  a  half  mile  or  1  mile  east  of  the  trail  here.  In  the 
eastern  part  of  section  9  this  beach  is  aboiit  25  rods  wide,  rising  5  feet 
from  its  east  side,  and  descending'  10  feet  to  its'  western  base,  which  was 
the  margin  of  Lake  Agassiz. 

Thence  the  upper  beach  extends  nearly  due  nortli  through  the  east 
edge  of  section  4,  Sundal,  and  section  33,  Garfield.  In  the  east  edge  of 
the  southeast  quarter  of  section  28  and  the  west  edge  of  the  northwest 
quarter  of  section  27,  Garfield,  it  is  a  typical  ridge  of  gravel  and  sand, 
with  its  crest  1,166  to  1,173  feet  above  the  sea.  There  is  a  gradual  descent 
toward  the  west.  The  depression  on  the  east  is  a  sixth  to  a  fourth  of  a 
mile  wide,  sinking  6  to  10  feet  below  the  beach.  Farther  eastward  the 
land  is  moderately  undulating  till,  rising  20  to  30  feet  above  the  beach  and 
bearing  frequent  groves  of  small  poplars,  bur  oak,  and  canoe  birch. 

Water  in  the  Sand  Hill  River  at  tlie  ford  of  the  old  Pembina  trail,  in 
the  west  part  of  section  28,  Garfield,  ordinary  low  stage,  July  26,  1881, 
1,071  feet. 


298  THE  GLACIAL  LAKE  AGASSIZ. 

DELTA    OF    THE    SAND    HILL    RIVEE. 

(PLATES   XXV   AND   XXVI.) 

When  Lake  Agassiz  stood  at  its  greatest  height,  the  Sand  Hill  River 
brought  into  its  margin  n  delta  6  miles  long  from  south  to  north  and  3 
miles  wide,  reaching-  from  the  upjjer  beach  to  the  west  side  of  Garfield  and 
Snndal  townships  (fig.  12).  This  deposit  of  stratified  gravel  and  sand  has 
about  an  equal  area  and  thickness  with  the  delta  of  the  Buffalo  River  at 
Muskoda.  Its  surface  descends  slowly  westward  and  is  crossed  by  the 
lower  Herman  and  the  Norcross  shores,  though  these  lake  levels  are  not 
generallv  traceable.  The  Tintah  shores  pass  along  its  western  margin, 
which  in  some  portions  was  worn  away  to  a  low  escarpment,  steeper  than 
its  original  frontal  slope,  while  tlie  eroded  sand  and  gravel,  after  being 
carried  some  distance  southward,  l)ut  not  Avholly  l^eyond  the  delta,  were 
deposited  in  beach  ridges.     Upon  the  delta  plain  many  dunes  of  small  and 

fierman  Beac/t 


yy  ^__^ ■■^:^^^^"~5Tff/)T/r/SO  DSLTA,  SAND  >»/V/7  a«4l<«___Z^ \  o     -^  _      _ 

lOOO 

"  ^^jts^^^^"^i^^^MMW=^MWM^ 

Fig.  12. — Section  across  the  delta  of  the  Sand  Hill  River.    Horizontal  scale,  one-half  mile  to  an  inch. 

large  size,  seen  from  a  distance  of  10  or  12  miles  across  the  lower  expanse 
at  the  west,  have  been  heaped  up  by  the  winds,  probably  mostly  before 
vegetation  had  spread  over  this  area  after  the  withdrawal  of  the  glacial  lake. 
As  was  stated  on  page  291,  in  the  description  of  the  Buffalo  delta, 
both  these  river  deposits  in  the  edge  of  Lake  Agassiz  seem  attributable  to 
conditions  of  the  recession  of  the  ice-sheet.  Their  gravel  and  sand  were 
doubtless  mainly  englacial  drift  and  were  brought  into  this  lake  by  streams 
which  had  gathered  their  freight  upon  the  ice  surface  during  the  time  of 
formation  of  terminal  moraines.  One  of  these  glacial  rivers,  supplying  a 
part  or  perhaps  nearly  all  of  the  Sand  Hill  delta,  flowed  from  an  angle  of 
the  ninth  or  Leaf  Hills  moraine  in  a  channel  which  has  been  traced  16 
miles  to  its  junction  with  the  Sand  Hill  River,  as  described  on  page  164. 
Its  sand  and  fine  silt  were  carried  more  than  30  miles  by  the  strong  current 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH    XXV.    PL.  XXVL 


MAP  OF  THE  EASTERN  SHORES  OF  LAKE  AGASSIZ  IN  THEA^CINm'OF  MAPLE  I.AKE    ^\NO 
NORTHWARD,  IN  POLIv  AND   MARSHALL    COUNTIES, MI NNK SOTA  . 

Scale  .  6  miles  to  an  inch . 


T.ake  Area 


Delia 


AUitudes    of  rcUln-wy  stations    are     noted    in    feet      above    the     sea. 


THE  SAND  HILL  DELTA.  299 

of  tlie  river  in  its  irreg-ular  course  before  they  were  deposited  in  Lake 
Agassiz,  where  they  at  once  settled  to  the  bottom  of  the  still  water. 

In  the  south  half  of  section  32,  Grarfield,  and  in  a  belt  which  thence 
extends  approximately  north  and  south,  the  siirface  of  this  delta,  as  it  was 
orig-inally  deposited,  falls  toward  the  west  with  a  slope  of  25  or  30  feet  in  1 
mile,  from  1,125  or  1,130  feet  to  about  1,100  feet  above  the  sea.  Beneath 
this  plane,  however,  channels  have  been  eroded  by  the  winds,  and  .sand  hills 
25  to  75  feet  above  it  have  been  blown  up  in  irregular  groups  and  series, 
scattered  over  a  tract  about  a  mile  wide  and  extending  3  or  4  miles  south- 
ward from  the  Sand  Hill  River,  in  section  29,  the  northeast  part  of  section 
30,  and  in  sections  31  and  32,  Garfield,  and  reaching  southward  in  sections 
5  and  8,  Sundal.  The  most  southern  of  these  hills  is  an  isolated  group 
in  the  east  part  of  the  northeast  quarter  of  section  18,  Sundal.  Another 
isolated  group  lies  north  of  the  Sand  Hill  River,  in  the  northwest  quarter 
of  section  16,  Garfield.  These  sand  dunes  are  in  part  bare,  being  so  fre- 
quently drifted  by  the  winds  as  to  allow  no  foothold  for  vegetation ;  other 
portions  are  clothed  with  grass  or  with  bushes  and  scanty  dAvarfed  trees, 
including  bur  oak,  the  common  aspen  or  poplar,  cottonwood,  green  ash, 
black  cherry,  and  the  frost  grape. 

Elevations  of  the  highest  points  of  these  dunes,  in  order  from  south  to 
north,  are  approximately  1,190,  1,180,  and  1,200  feet.  The  highest  dune 
appears  to  be  in  or  near  the  east  half  of  the  northeast  quai'ter  of  section 
30,  Garfield. 

Second?  y  Herman  beach,  a  smoothly  rounded  ridge  of  gravel  and 
sand  10  to  15  feet  high  above  the  adjacent  level,  1,148  to  1,153  feet  above 
the  sea,  about  three-fourths  of  a  mile  east  of  the  old  Pembina  trail,  in  tlie 
west  half  of  sections  21  and  16,  Garfield,  extending  1^  miles  north  from 
the  Sand  Hill  River  to  tlie  cluster  of  dunes  in  the  northwest  quarter  of 
section  16. 

VICINITY    OP    MAPLE    LAKE. 

(PLATE   XXVI.) 

The  ujjper  Herman  beach,  the  fii'st  of  the  series  which  was  formed  in 
the  vicinity  of  Maple  Lake  contemporaneously  witli  the  single  Herman 
beach  farther  south,  runs  approximately  from  south  to  north,  through  or 


300  THE    GLACIAL  LAKE  AGASSIZ. 

near  the  northeast  corner  of  section  4,  Garfield  It  is  a  smooth  gravel 
ridge,  in  some  parts  hidden  by  scattered  groves,  with  its  crest  1,165  to 
1,175  feet  above  the  sea.  Farther  east  is  a  large  area  of  woodland.  The 
second  Herman  beach,  in  the  east  part  of  section  5,  this  township,  and  sec- 
tion 32,  Godfrey,  about  a  mile  west  from  the  upper  beach,  has  a  heiglit  of 
1,149  to  1,153  feet,  being  a  ridge  of  gravel  and  sand  about  40  rods  wide, 
with  very  gentle,  prolonged  slopes  toward  both  the  east  and  west.  Natiu-al 
si^rface  at  the  northeast  comer  of  section  32,  Godfrey,  1,146  feet.  Third 
Herman  beach,  running  north,  in  the  northwest  quarter  of  section  5,  Gar- 
field, and  the  west  part  of  section  32,  Godfrey,  a  half  or  two-thirds  of  a 
mile  west  from  the  last,  1,130  to  1,135  feet,  consisting  of  a  distinct  ridge 
in  its  southern  part,  but  farther  north  being  a  flat  area  of  gravel  and  sand, 
slightly  elevated  above  the  land  next  east. 

Second  Herman  beach,  a  broad,  low  ridge  of  gravel  and  sand,  extend- 
ing north-northeast  through  section  28,  Godfrey,  from  its  southwest  corner 
to  its  north  line,  1,148  to  1,150  feet.  The  northward  continuation  of  this 
beach  is  a  low,  flattened  ridge,  the  western  one  of  two  parallel  ridges  of 
gravel  below  that  of  the  upper  beach,  extending  northeasterly  and  north- 
erly through  or  near  the  west  edge  of  section  10,  Godfrey,  1,150  to  1,154 
feet.  Through  the  next  3  miles  in  section  3,  Godfrey,  and  in  the  east  part 
of  sections  35  and  26  and  the  northwest  quarter  of  section  25,  Tilden,  it  is 
a  prominent' beach  ridge,  with  its  crest  at  1,153  to  1,161  feet,  somewhat 
steep  on  its  east  side,  which  descends  about  10  feet  to  a  belt  of  lowland 
and  marsh  that  divides  it  from  the  parallel  beach  a  quarter  to  a  third  of  a 
mile  east. 

The  eastern  one  of  these  parallel  beach  ridges  is  only  8  or  10  feet  below 
the  average  elevation  of  the  iipper  beach.  It  probably  marks  a  slight  rise 
of  the  land  here ;  but  no  corresponding  beach  formation  has  been  observed 
on  this  latitude  in  North  Dakota.  It  is  clearly  continuous  8  miles,  the  first 
4  miles  extending  northerly  and  the  next  4  miles  easterly.  These  parts  are 
connected  in  section  25,  Tilden,  by  a  graceful  curve,  that  portion  of  this 
beach  and  its  extent  thence  eastward  being  known  as  the  "Attix  ridge," 
from  Hemy  and  William  Attix,  brothers,  who  have  built  their  houses  upon 
it.     In  its  northward  course,  nearly  tlu-ough  the  middle  of  sections  10  and 


HEEMAN  BEACHES  I^EAE  MAPLE  LAKE.  301 

4,  Godfrey,  its  crest  is  at  1,158  to  1,163  feet;  in  the  west  edge  of  section 
36,  Tilden,  and  along  its  curved  course  to  the  northeast  and  east  at  the 
west  and  north  sides  of  section  25  and  in  the  southeast  part  of  section  24, 
Tilden,  1,163  to  1,168  feet,  and  in  sections  21  and  22,  Grove  Park,  1,171 
to  1,173  feet.  A  slough,  a  third  to  a  half  of  a  mile  wide,  extends  along 
the  east  side  of  this  beach  in  section  3,  Godfrey,  and  in  the  southeast  part 
of  Tilden,  having  a  height  of  1,155  to  1,160  feet. 

Upper  beach  in  the  southwest  quarter  of  section  11,  Godfrey,  forming 
a  plain  of  stratified  gravel  and  sand  a  quarter  or  a  third  of  a  mile  wide 
from  east  to  west,  1,168  to  1,173  feet.  This  beach  near  the  south  side  of 
section  1 1  becomes  a  distinct  gravel  ridge  of  the  usual  character,  about  25 
rods  wide,  with  its  crest  at  1,173  feet,  bordered  by  a  slough  20  to  40  rods 
wide  at  its  east  side.  About  a  third  of  a  mile  farther  southeast  and  some 
50  rods  west  of  the  southwest  extremity  of  Maple  Lake,  in  section  14, 
Godfrey,  the  elevation  of  this  beach  ridge  is  1,175  to  1,178  feet. 

Maple  Lake,  water  surface  July  28,  1881,  1,169  feet.  This  lake,  6 
miles  long  and  averaging  about  a  half  mile  wide,  has  a  maximum  depth  of 
20  feet  near  its  southwestern  end,  and  is  mainly  10  to  15  feet  deep  along 
its  central  portion. 

Upper  beach,  top  of  its  well-marked  gravel  ridge  in  the  east  edge  of 
the  northeast  quarter  of  section  3,  Godfrey,  about  20  rods  north  of  Mr. 
Horton's,  1,180  feet.  Beyond  this  point,  through  its  next  2J  miles,  curving 
from  a  northward  to  a  northeastward  and  eastward  course,  this  upper  beach 
of  Lake  Agassiz  is  magnificently  exhibited,  forming  a  massive,  gently 
rounded  i-idge  of  gravel  and  sand  about  30  rods  across,  with  its  crest  1,178 
to  1,186  feet  above  the  sea.  A  view  of  this  beach  ridge  is  given  in  PI.  VI 
(jjage  26),  taken  on  its  top,  near  the  south  line  of  the  southeast  quarter  of 
section  35,  Tilden,  and  looking  northeastward  along  its  course.  It  is  bor- 
dered on  the  southeast  side  by  a  tract  of  slightly  undulating  till  10  to  15 
feet  lower,  mostly  covered  with  small  timber  and  brush  and  holding  fre- 
quent sloughs  and  lakelets  in  its  depressions.  The  top  of  the  beach  is  not 
wooded,  but  small  trees  and  bushes  originally  encroached  upon  its  slopes. 
A  road  extends  along  the  crest  of  its  curving  portion  for  a  distance  of 
about  a  mile  through  section  36,  Tilden. 


302  THE  GLACIAL  LAKE  AGASSIZ. 

The  marsh  which  borders  the  northwest  side  of  the  northeast  j^art  of 
Maple  Lake  shows  a  descent  of  5  to  7  feet  northwestward,  or  away  from 
the  lake,  in  its  width  of  1  to  li  miles.  Maple  Lake  is  prevented  from  flow- 
ing in  this  direction  by  a  beaver  dam  near  the  lake.  The  creek  draining 
this  marsh  where  it  intersects  the  upper  beach  near  the  east  line  of  the 
northeast  quarter  of  section  27,  Grove  Park,  has  a  height  of  1,163  feet. 
Here  the  beach  skirting  the  north  side  of  the  marsh  is  a  flat  deposit  of 
gravel  and  sand,  a  fourth  to  a  half  of  a  mile  or  more  in  width,  highest  next 
to  the  marsh,  above  which  it  rises  5  to  8  feet  in  a  moderate  slope.  Its  ele- 
vation in  the  north  half  of  sections  26  and  27  is  1,169  to  1,172  feet,  being 
even  1  or  2  feet  lower  than  the  Attix  ridge,  which  lies  some  two-thirds  of  a 
mile  farther  north,  in  the  south  half  of  sections  21  and  22.  This  belt  of 
beach  gravel  and  sand  continues  6  miles  in  a  nearly  due-east  course,  and 
beyond  that  it  extends  still  eastward  along  the  north  side  of  a  great  tama- 
rack swamp,  which  begins  in  section  34,  Badger,  and  is  said  to  be  8  miles 
long.  Maple  Lake  and  this  tamarack  swamp  hold  the  same  relation  to  the 
upper  beach  ridge,  which  was  a  barrier  between  them  and  Lake  Agassiz 
and  which  now  wholly  or  partially  obstructs  the  di'ainage  of  these  areas. 

Third  Herman  beach,  a  small  ridge  of  gravel  and  sand,  extending  from 
southwest  to  northeast,  8  to  10  rods  wide,  and  rising  4  or  5  feet,  crossed 
by  the  Crookston  road  in  the  southwest  quarter  of  section  23,  Tilden,  and 
seen  to  reach  at  least  a  mile  each  way  from  this  road,  1,146  to  1,149  feet. 

Natural  surface  at  the  southeast  corner  of  section  15,  Tilden,  1,134  feet. 

Fourth  Herman  beach,  crossed  by  the  road  to  Crookston  and  Red 
Lake  Falls  near  the  center  of  the  southeast  quarter  of  this  section  15, 
1,132  to  1,134  feet.  This  is  a  well-marked  gravel  ridge,  mainly  single, 
but  twofold  where  it  is  crossed  by  this  road.  The  distance  of  1  mile  here 
between  these  third  and  fom-th  Herman  beaches  consists  of  till,  with  a 
nearly  smooth  surface,  which  has  bowlders  up  to  3  and  rarely  5  feet  in 
diameter  quite  numerously  scattered  over  it.  Southeastward  from  the  third 
to  the  first  or  upper  beach  the  surface  mostly  is  sand  and  gravel,  with  no 
bowlders. 


HERMAN  BEACHES  NEAE  RED  LAKE.  303 

EASTWARD    TO    RED    LAKE    AND    THE    BIG    FORK    OF    RAINY    RIVER. 

(PLATES   III   AND  XII.) 

A  portion  of  a  shore-line  of  Lake  Agassiz,  probably  the  highest  in  the 
Herman  series  of  beaches,  has  been  observed  on  and  near  the  southwest 
line  of  the  Red  Lake  Indian  Reservation,  between  Hill  and  Lost  rivers.  It 
was  seen  near  the  north  side  of  sections  31  and  32,  and  in  the  central  part 
of  sections  27  and  26,  township  150,  range  40,  also  for  a  mile  or  more 
thence  eastward  in  the  reservation,  being  15  to  20  miles  east-northeast  of 
Maple  Lake.  The  area  is  mostly  prairie,  and  the  beach  is  well  exhibited. 
In  the  southwest  part  of  township  150,  range  40,  the  beach  ridge  of  coarse 
gravel  runs  along  the  northern  border  of  a  roughly  morainic  belt,  which  is 
a  half  to  two-thirds  of  a  mile  wide.  In  sections  27  and  26,  and  onward  in 
the  Red  Lake  Reservation,  the  beach  is  a  typical  gravel  and  sand  ridge, 
containing  pebbles  and  cobbles,  nearly  all  of  Archean  gneiss  and  crystal- 
line schists,  up  to  6  and  8  inches  in  diameter.  Its  trend  here  for  about  3 
miles  is  nearly  from  west  to  east.  On  the  south,  within  about  1  mile,  is 
a  tyjncal  morainic  belt  of  many  hillocks,  knolls,  and  ridges,  which  cover  a 
width  of  several  miles  and  rise  100  to  150  feet  above  the  beach  and  the 
low,  nearly  flat  tract  that  was  covered  by  Lake  Agassiz  on  the  north,  con- 
sisting in  large  part  of  marshes,  through  which  the  Lost  and  Clearwater 
rivers  flow  westward  in  meandering  courses. 

About  25  miles  farther  east  in  the  Red  Lake  Reservation  the  road 
from  Red  Lake  to  White  Earth  crosses  a  beach  of  Lake  Agassiz,  which  is 
probably  the  highest,  being  a  continuation  of  the  foregoing.  This  beach 
runs  nearly  from  west  to  east,  and  is  approximately  40  feet  above  Red 
Lake,  or  1,210  feet  above  the  sea.  It  is  a  ridge  of  sand  and  fine  gravel, 
crossed  by  the  road  about  2  miles  southwest  from  Big  Rock  Creek  and 
Shell  Lake.  A  grove  of  red  pines  grows  on  the  beach,  but  the  till  on  each 
side  bears  white  pmes.  Following  the  road  to  the  southwest,  a  belt  of 
kames  is  entered  about  tliree-fourths  of  a  mile  from  the  beach,  which  con- 
tinues to  Sandy  River,  having  a  sm-face  of  many  knolls  and  short  ridges, 
with  no  observable  parallelism  in  their  trends,  the  crests  being  10  to  20  feet 
above  the  inclosed  hollows. 


304  THE  GLACIAL  LAKE  AGASSIZ. 

The  most  easteru  observation  of  the  upper  shore-hue  of  Lake  Agassiz 
in  northern  Minnesota  is  by  Mr.  Horace  V.  AViuchell,  on  the  Bowstring 
River,  more  commonly  known  as  the  Big  Fork  of  Rainy  River,  some  60 
miles  east  of  Red  Lake.  In  his  description  of  the  asceut  of  this  stream 
Mr.  Winchell  writes  as  follows  of  the  locality,  probably  about  1,250  feet 
above  the  sea,  where  the  surface  changes  from  a  smooth  contour  on  the 
north,  indicating  lacustrine  action,  to  a  more  undulating  and  rolling  con- 
toui-  on  the  south,  above  the  level  of  Lake  Agassiz : 

At  the  eud  of  7 J  miles  the  foot  of  a  rapid  uearly  one-lialf  a  mile  long  is  reached. 
At  the  foot  of  it  is  a  bank  of  gravel  and  sand  [iirobably  the  beach  of  Lake  Agassiz]. 
It  is  a  very  different  sort  of  bank  from  those  seen  below  here.  It  is  stratified,  or  par- 
tially so,  but  not  horizontally  nor  all  in  the  same  direction.  It  looks  like  a  stratilied 
river  deposit.  Under  it  crops  out  a  little  line  bluish-gray  clay,  of  which  only  a  foot 
or  two  can  be  seen.  This  is  supposed  to  be  Cretaceous.  *  *  *  There  are  many 
limestone  pebbles  iu  the  bank  above  the  clay,  but  no  shale  is  seen  in  it. 

This  rapid  is  over  an  immense  number  of  bowlders.  Most  of  them  are  horn- 
blendic  gneiss,  but  other  rocks  are  frequent.  Many  of  the  bowlders  are  large  and 
stick  up  several  feet  above  the  water.  A  short  distance  up  the  rapid  is  a  small  island 
which  seems  to  be  made  of  bowlders  and  is  covered  with  trees  and  bushes.    *     *     * 

Above  the  rapids  qiaau titles  of  bowlders  are  seen,  while  below  only  a  few  were 
encountered.  The  country  does  not  seem  to  be  of  one  general  level,  as  before,  but  is 
knolly.  The  banks  are  of  sand  and  gravel  and  contain  much  more  gravel  than  those 
below  the  rapids.  This  is  about  95  miles  up  the  river,  probably  in  township  62,  range 
25.  It  seems  probable  that  the  rapid  mentioned  above  is  on  the  boundary  or  shore  of 
the  glacial  Lake  Agassiz,  and  that  all  of  the  river  below  this  rapid  is  included  in  the 
ancient  basin.' 

BELTRAMI    ISLAND. 

The  recent  survey  for  the  Duluth  and  Winnipeg  Railroad,  passing 
northwest  by  the  east  end  of  Red  Lake  and  the  southwest  side  of  the  Lake 
of  the  Woods,  shows  that  the  former  of  these  lakes  lies  about  40  feet  and 
the  latter  somewhat  more  than  150  feet  below  the  highest  level  of  Lake 
Agassiz.  The  height  of  Red  Lake  above  the  sea  is  ascertained  to  be  1,172 
feet,  and  of  the  Lake  of  the  Woods,  in  its  stages  of  low  and  high  water, 
1,057  to  1,063  feet.  Northeast  of  Red  Lake  the  Tamarack  River  drains  a 
lai'ge  tract  of  tamarack,  spruce,  and  arbor-vitse  swamp,  which  reaches  to 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Sixteentli  Annual  Report,  for  1887,  p.  434. 


BELTRAMI  ISLAND.  305 

the  divide  between  the  Tamarack  River  and  the  West  Branch  of  the  Bow- 
string River  (more  commonly  called  the  Big  Fork),  tributary  to  Rainy 
River,  the  height  of  the  divide  being  only  15  to  20  feet  above  Red  Lake. 
Similar  low  swamp  land  forms  nearly  the  whole  northern  and  northwestern 
shore  of  Red  Lake  and  is  crossed  by  this  railroad  survey  continuously 
along  its  first  18  miles  beyond  Red  Lake;  but  at  a  distance  of  29  miles 
from  the  lake  the  profile  shows  an  ascent  crossing  the  highest  beach  of 
Lake  Agassiz,  which  there  is  1,215  feet  above  tlie  sea.  The  next  17  miles 
of  the  profile  extend  across  the  northeastern  edge  of  a  large  island  of  Lake 
Agassiz,  rising  on  that  line  to  a  maximum  height  of  1,283  feet,  with  a 
moderately  undulating  drift-covered  surface.  In  the  next  15  miles,  which 
comprise  the  descent  on  a  similar  but  smoother  drift  surface  from  the  high- 
est shore  of  Lake  Agassiz  to  the  War  Road  River,  an  affluent  of  the  Lake 
of  the  Woods,  the  profile  crosses  a  succession  of  ten  lower  beaches  of 
Lake  Agassiz,  marking  stages  in  the  gradual  uplifting  of  the  land  and 
subsidence  of  the  lake,  their  altitudes  above  the  sea  being  1,196,  1,172, 
1,156,  1,143,  1,127,  1,116,  1,106,  1,099,  1,093,  and  1,087  feet. 

These  data  show  that  Lake  Agassiz  in  its  highest  stage  had  a  large 
island  northwest  of  Red  Lake,  comprising  the  headwaters  of  numerous 
streams  flowing  outward  from  it  to  the  Lake  of  the  Woods,  Rainy  River, 
Red  Lake,  the  Red  Lake  River,  and  the  Red  River  of  the  North.  This 
island  had  probably  a  diameter  of  40  miles  or  more,  with  an  area  exceed- 
ing 1,000  square  miles,  of  which  apparently  more  than  half  is  in  Beltrami 
County,  the  portion  farther  west  being  chiefly  in  Marshall  County,  Minn. 
For  this  tract,  which  had  before  been  supposed  to  be  comparatively  low 
and  perhaps  wholly  beneath  the  highest  level  of  Lake  Agassiz,  the  name 
Beltrami  Island  is  proposed,  in  recognition  of  the  exploration  of  the  region 
of  Red  Lake  and  the  Julian  or  most  northern  sources  of  the  Mississippi  by 
Beltrami  in  1823.^  As  Prof  N.  H.  Winchell  wrote  in  the  historical  sketch 
here  cited,  this  district  "is  still  nearly  as  wild  and  uninhabited  as  when 
Mr.  Beltrami  passed  through  it."  The  limits  of  Beltrami  Island  are  shown 
approximately  on  Pis.  X,  XXII,  and  other  maps  in  this  volume.^ 

1  Geology  of  Minnesota,  Vol.  I,  1884,  pp.  44-50,  with  map. 

■'  Beltrami  Island  was  first  described  in  the  American  Geologist,  Vol.  XI,  pp.  423-125,  .Iiine,  1893; 
and  its  earliest  mapping  was  in  the  Twenty-second  Annual  Report  of  the  Geol.  and  Nat.  Hist.  Survey 
of  Minnesota,  for  1893  (pub.  1894),  Plate  I. 

MON  XXV 20 


306  THE  GLACIAL  LAKE  AGASSIZ. 

This  island  lies  in  the  course  of  northwestward  and  northward  contin- 
uation of  the  Mesabi  or  eleventh  moraine  of  the  series  mapped  in  Minnesota, 
which  next  east  from  the  narrows  of  Red  Lake,  rises  very  prominently  to  a 
height  of  150  to  200  feet  for  a  distance  of  about  10  miles  upon  the  penin- 
sula dividing  the  northern  and  southern  parts  of  the  lake.  Like  nearly  the 
entire  western  half  or  two-thirds  of  Minnesota,  this  whole  region  is  deeply 
drift-covered.  No  outcrops  of  the  bed-rocks  have  yet  been  found  on  the 
large  portion  of  the  Red  River  basin  lying  in  Minnesota;  but  the  conspic- 
uous escarpment  of  Cretaceous  shales,  overspread  by  drift,  along  the  Avest 
border  of  the  Red  River  Valley,  wells  penetrating  to  Cretaceous  beds  along 
this  great  valley  plain,  and  the  topographic  features  of  the  land  rising  east- 
ward from  it  with  nearly  the  same  rate  of  ascent  as  on  the  west,  lead  to  the 
belief  that  the  eastern,  like  the  western,  border  of  this  wide  valley  is  foi'med 
by  an  escarpment  of  Cretaceous  shales  beneath  the  drift,  and  that  the  mod- 
erately elevated  area  of  Beltrami  Island  consists  of  these  shales  enveloped 
by  the  glacial  and  modified  drift. 

THE  UPPER  OR  HERMATf  BEACHES  AlVB  DEETAS  IK  NORTH 

DAKOTA. 

FKOM    LAKE    TRAVERSE    NORTHWEST    TO    MILNOR. 

(PLATES   XXIII   AND   XXVII.) 

From  the  soiithern  extremity  of  Lake  Agassiz,  in  section  18,  Leon- 
ardsville.  Traverse  County,  Minn.,  the  upper  or  Herman  beach  extends 
northwestward  75  miles  to  the  most  southern  bend  of  the  Sheyenne  River, 
in  Ransom  County,  N.  Dak.,  and  thence  its  course  is  nearly  due  north,  but 
with  slight  deflection  westward,  to  the  international  boundary.  The  mouth 
of  Lake  Agassiz  was  where  now  a  slough  2  to  3  miles  wide,  with  frequent 
areas  of  open  water,  tributary  to  the  Bois  des  Sioux  River,  stretches  north- 
ward from  the  northeast  end  of  Lake  Traverse.  On  the  west  side  of  this 
slough  and  of  Lake  Traverse  bluffs  of  till  rise  100  to  125  feet;  their  tops 
and  the  rolling  surface  of  till  which  extends  thence  westward  are  1,070  to 
1,100  feet  above  the  sea. 

The  beginning  of  the  upper  or  Herman  shore-line  west  of  the  Bois 
des  Sioux  is  in  the  northeast  corner  of  South  Dakota,  in  sections  10,  3,  and 


HEEMAN  BEACH  ENTERING  NORTH  DAKOTA.  307 

4,  township  128,  range  48,  nearly  2  miles  soutli  from  the  north  line  of  the 
Sisseton  and  Wahpeton  Reservation.  The  ancient  shoi'e  rises  with  terrace- 
like steepness  20  or  30  feet  above  the  surface  of  undulating  till  which 
borders  it  on  the  northeast.  Its  material  is  sand  and  gravel,  with  pebbles 
up  to  IJ  or  2  inches  in  diameter,  about  half  of  which  are  limestone. 
Beyond  its  steep  margin  this  deposit  of  gravel  forms  a  belt  about  a  mile 
wide,  approximately  level,  but  with  frequent  short  swells  and  low,  flattened 
ridges,  5  to  10  or  15  feet  above  the  intervening  depressions.  Its  elevation 
is  1,060  to  1,070  feet  above  the  sea,  or  from  90  to  100  feet  above  Lake 
Traverse. 

For  its  first  3  or  4  miles  the  terrace-like  lakeward  margin  of  this  belt 
of  sand  and  gravel  sweeps  with  a  gentle  curve  westerly  and  northerly  to  a 
point  in  the  southwest  quarter  of  section  34,  townsliip  129,  range  48,  where 
it  turns  quite  abruptly,  taking  a  nearly  due-west  course  for  the  next  3  miles 
to  the  west  side  of  section  31  of  this  township. 

In  the  northwest  quarter  of  section  3,  township  128,  range  48,  a  third 
of  a  mile  east  of  W.  J.  Allen's  house,  the  ascent  at  the  margin  of  this 
deposit  is  about  10  feet,  to  an  elevation  of  1,060  feet,  approximately.  Tlie 
belt  of  sand  and  fine  gravel  is  here  about  a  half  mile  wide.  Occasional 
hummocks,  rising  5  to  10  feet  and  50  to  100  feet  long,  which  were  observed 
on  this  part  of  the  belt,  appear  to  have  been  heaped  up  by  the  wind  before 
the  protecting  mantle  of  grass  and  other  herbaceous  vegetation  was  spread 
over  it. 

Where  this  formation  enters  North  Dakota,  in  the  southeast  quarter  of 
section  32,  township  129,  range  48,  similar  dunes,  1,075  to  1,080  feet  above 
the  sea,  have  been  excavated  for  use  as  plastering  sand.  Nearly  all  por- 
tions of  this  tract,  and  even  its  dunes,  are  now  covered  with  a  black  soil  and 
plentiful  vegetation;  but  certain  species  preferring  dry,  sandy  soil,  as  the 
dwarf  rose  (Rosa  arkansana  Porter),  grow  in  greater  abundance  on  the  sand 
and  gravel  belt,  and  especially  among  its  hummocks  and  hollows,  than  on 
the  flat  or  slightly  undulating  surface  of  till  at  each  side. 

The  imier  margin  of  this  belt,  marking  the  shore  of  Lake  Agassiz  at 
its  maximum  stage,  passes  in  its  western  course  about  60  rods  north  of  the 
southeast  corner  of  section  32    and   turns   again  to  the  northwest  near 


308  THE  GLACIAL  LAKE  AGASSIZ. 

the  middle  of  the  west  side  of  section  31,  township  129,  range  48.  At  the 
latter  locality  it  is  a  low,  wave-like  ridge  of  sand  and  fine  gravel,  about 
1,060  feet  above  the  sea.  On  the  south  it  is  bordered  by  land  3  to  5  feet 
lower  for  a  width  of  IJ  miles.  J.  R.  Grimesey's  well,  13  feet  deep,  at  the 
southwest  corner  of  section  31,  on  this  low  tract  outside  the  beach  ridge, 
encountered  only  very  fine  stratified  sand,  irregularly  laminated  and  con- 
taining numerous  tubular  limonitic  concretions.  Farther  to  the  southwest 
and  west,  a  gently  undulating  surface  of  till,  scarcely  higher  than  the  beach 
of  Lake  Agassiz,  stretches  away  several  miles,  beyond  which  the  high- 
land of  the  Coteau  des  Prairies  is  seen  in  the  far  distance. 

The  Herman  beach  crosses  township  129,  range  49,  in  a  diagonal 
course,  entering  it  a  half  mile  north  of  its  southeast  corner  and  running- 
northwest  to  the  north  side  of  sections  5  and  6.  In  section  23  and  the 
northeast  part  of  section  22,  its  elevation  is  about  1,055  feet,  but  its  dunes 
rise  3  or  4  feet  higher.  At  the  middle  of  the  north  side  of  section  16  it  is 
a  ridge  of  sand  and  fine  gravel  about  8  rods  wide,  rising  4  to  6  feet  above 
the  land  on  each  side.  Its  crest  here  and  for  a  mile  to  the  southeast 
and  northwest  is  1,060  to  1,065  feet  above  the  sea.  Northeastward  the 
surface  falls  about  20  feet  in  the  first  mile.  On  the  southwest  side  of  this 
distinct  beach  ridge,  a  smooth,  slightly  undulating  tract  IJ  to  2  miles  wide, 
extending  through  this  township,  consists  of  sand  and  fine  clayey  silt.  Its 
elevation  varies  from  1,055  to  1,080  feet,  attaining  the  latter  height  in  the 
northwest  part  of  the  township.  This  belt,  with  its  continuation  southeast- 
ward, previously  described,  was  doubtless  covered  by  Lake  Agassiz  before 
the  erosion  of  its  outlet  to  the  level  of  the  Herman  beach;  but  its  stratified 
sand  and  silt  appear  to  be  modified  drift  deposited  by  streams  from  the 
melting  ice-sheet.  The  glacial  recession  here  was  from  southwest  to  north- 
east, and  this  was  probably  an  avenue  of  di-ainage  during  a  short  time,  as 
was  shown  on  page  150,  till  the  continued  retreat  of  the  ice  left  a  consider- 
able expanse  of  water,  the  begimiing  of  Lake  Agassiz,  between  itself  and 
the  shore. 

In  the  north  part  of  sections  5  and  6,  township  129,  range  49,  and  in 
sections  31  and  32,  township  130,  range  49,  this  beach  consists  of  two  or 


THE  LIGHTNINGS  NEST.  309 

three  parallel  wave-like  ridges  of  gravel  and  sand,  divided  hj  depressions 
an  eighth  to  a  quarter  of  a  mile  wide  and  5  to  10  feet  lower. 

This  belt  reaches  north  to  the  Lightnings  (or  Thunders)  Nest/  a  mas- 
sive dune  of  fine  sand  (PI.  VII,  p.  28),  partly  bare  and  now  wind-blown, 
but  mostly  covered  with  bushes  and  herbage,  situated  near  the  center  of 
section  30,  township  130,  range  49.  Its  base  on  the  south  is  1,060  feet  and 
its  top  1,120  feet,  approximately,  above  the  sea.  It  covers  a  space  about 
a  quarter  of  a  mile  in  extent  from  southeast  to  northwest,  with  nearly  as 
great  width,  and  rises  in  two  summits  of  nearly  equal  height.  The  Light- 
nings Nest  is  the  most  prominent  in  a  series  of  dunes,  elsewhere  rising 
only  10  to  30  feet,  mostly  grassed,  which  extends  a  mile  or  more  to  the 
southeast  and  is  traceable  several  luiles  northwest  to  the  east  end  of  a  very 
conspicuous  tract  of  dunes  50  to  100  feet  above  the  adjacent  level,  with 
summits  at  1,100  to  1,150  feet  above  the  sea,  which  stretches  about  4  miles 
hi  a  west-northwest  course  in  the  south  part  of  township  131,  range  50,  1 
to  2  miles  south  of  the  Wild  Rice  River.  By  winds,  eroding  and  drifting, 
these  sand  hills  were  heaped  up  from  the  Hei'man  beach  and  its  associated 
belt  of  modified  drift,  probably  soon  after  the  retreat  of  the  ice,  though 
their  forms  have  been  constantly  changing  since  that  time. 

Outside  the  area  of  Lake  Agassiz,  the  southwest  part  of  Richland 
County  is  till,  mostly  undulating  or  moderately  rolling,  Ijut  in  part  promi- 
nentl}-  hilly,  with  rough  morainic  contour  and  abundant  bowlders.  Taylor 
Lake,  approximately  1,050  feet  above  the  sea,  2^  miles  west  of  the  Light- 
nings Nest,  is  a  very  beautiful  sheet  of  water,  bordered  by  a  sandy  shore 
and  a  large  grove  on  the  north,  and  by  a  shore  of  bowlders  and  morainic 
hills  50  to  150  feet  above  the  lake  on  the  west.  These  hills  and  most  of  the 
lakes  farther  west  in  this  county  have  no  timber.  Northeastward  the  area 
that  was  covered  by  Lake  Agassiz  is  mostly  smooth  and  nearly  flat  till, 
with  frequent  marshy  tracts  called  sloughs,  liut  with  only  very  rare  and 
small  lakelets. 

Swan  Lake,  3  miles  long,  reaches  from  section  3  to  section  7,  t(^wnship 
130,  range  51,  having  an  estimated  height  of  1,070  feet  above  the  sea,  with 

'  A  translation  of  the  aboriginal  Dakota  name. 


310  THE  GLACIAL  LAKE  AGASSIZ. 

undulating  till  6  to  10  feet  higher  on  the  northeast  and  10  to  20  feet  higher 
on  the  south  and  west. 

The  Herman  beach,  a  ridge  of  fine  sand,  20  to  25  rods  wide  and  about 
3  feet  high,  near  the  south  line  of  section  36,  township  132,  rang-e  52, 
trends  to  the  west-northwest,  and  has  a  height  of  1,065  feet,  approxi- 
mately. On  the  north,  the  exceedingly  flat  plain  of  Lake  Agassiz,  sinking 
very  slowly  northeastward,  reaches  as  far  as  the  eye  can  see.  On  the 
south,  flat  land,  covered  by  Lake  Agassiz  before  the  time  of  this  beach, 
continues  IJ  miles,  ascending  in  that  distance  from  1,060  feet  to  about 
1,080  feet,  and  moderately  undulating  till  rises  beyond  to  1,100  and 
1,125  feet. 

One  and  a  half  miles  north  of  this  beach  the  Wild  Rice  River  is 
crossed  by  a  bridge  near  the  center  of  section  25,  township  132,  range  52. 
The  stream  in  its  ordinary  stage  is  1  to  2  rods  wide,  with  a  depth  of  about 

3  feet,  and  is  filled  with  grass  and  rushes.  Its  bottom  land,  a  sixth  to  a  third 
of  a  mile  wide,  is  about  10  feet  higher  and  is  anniially  overflowed  by  the 
high  water  in  spring.  Its  bluffs  rise  about  40  feet  above  the  river  at  low 
water,  the  elevation  of  their  top  and  of  the  adjoining  plain  being,  approxi- 
mately, 1,050  feet.  These  bluffs  and  the  surface  from  the  Herman  beach 
north  to  Elk  Creek  are  till,  but  the  country  about  Wyndmere  and  south  to 
Elk  Creek  is  stratified,  fine  clayey  sand.  Both  formations  have  a  very  fer- 
tile soil,  unsurpassed  for  wheat  and  all  crops  proper  to  this  latitude.  Elk 
Creek  is  a  stream  similar  to  the  Wild  Rice  River,  but  smaller,  and  the  widtlr 
and  depth  of  its  valley  are  about  two-thu'ds  as  great. 

Northern  Pacific,  Fergus  Falls  and  Black  Hills  Railroad,  track  at 
Wyndmere,  1,062  feet  above  the  sea;  at  the  Herman  beach,  IJ  miles  west 
of  Wyndmere,  track  1,066  feet,  and  crest  of  the  beach  1,068  feet,  rising  8 
feet  above  the  adjacent  land  20  rods  away  both  east  and  west;  surface 
along  the  raih-oad  thence  westward  8  miles,  1,062  to  1,066  feet,  with  Star 
Lake,  a  third  of  a  mile  in  diameter  on  this  level  area,  only  2  or  3  feet  below 
the  surrounding  land  close  north  of  the  railroad  in  section  5,  township 
132,  range  52;  a  higher  beach  of  Lake  Agassiz,  crossed  3  miles  east  of 
Milnor,  and  therefore  called  the  Milnor  beach,  crest  and  track,  1,085  feet, 

4  or  5  feet  above  the  adjoining  land  10  rods  away  both  east  and  west; 


THE  MILNOE  BEACHES.  311 

another  beach  ridge  formed  during  the  same  stage  of  Lake  Agassiz,  a  third 
of  a  mile  farther  west,  crest  and  grade,  1,086  feet;  land  close  east,  1,081, 
and  west  1,087  feet;  track  at  Milnor,  1,097  feet. 

The  Herman  beach  west  and  north  of  Wyndmere  has  an  irregular  sur- 
face, with  frequent  hummocks  of  sand  heaped  5  to  10  feet  above  adjacent 
hollows.  Most  of  these  dunes  are  now  grassed.  From  near  Wyndmere 
this  beach,  with  frequent  small  dunes,  extends  north  through  the  west  edge 
of  township  133,  range  61,  and  thence  westerly  to  another  tract  of  promi- 
nent dunes  50  to  100  feet  above  the  adjacent  surface,  with  their  top  at  1,100 
to  1,150  feet,  which  extends  about  10  miles  in  a  west-northwest  course 
from  the  southwest  part  of  township  134,  range  52,  to  the  east  part  of  town- 
ship 134,  range  54,  terminating  about  2  miles  east  of  the  Sheyenne  River. 
Like  the  similar  high  dunes  south  of  the  Wild  Rice  River,  these  are  mainly 
covered  by  herbage,  bushes,  and  small  trees;  but  many  portions  are  now 
being  drifted  by  the  winds,  so  that  they  are  wholly  destitute  of  ve  getation. 
These  dunes  mark  the  course  of  the  Herman  beach,  here  greatly  increased 
in  volume  by  delta  deposits  from  the  Sheyenne  River. 

Morainic  knolls  and  hills,  rising  20  to  50  feet,  with  plentiful  bowlders, 
lie  close  west  of  Milnor,  extending  in  a  belt  from  southeast  to  northwest. 
They  are  referred  to  the  seventh  or  Dovre  moraine,  as  described  in  Chapter 
IV.  Near  Lisbon,  about  15  miles  northwest  from  Milnor,  some  of  these 
morainic  hills  are  quite  conspicuous,  rising  100  feet  or  more  above  the  sur- 
rounding country. 

Evidence  of  a  stage  of  Lake  Agassiz  20  or  30  feet  higher  than  that  of 
the  Herman  beach  is  found,  as  before  noticed,  in  many  places  along  the 
southern  part  of  its  boundary  in  North  Dakota.  The  portion  of  this  glacial 
lake  formed  earliest  by  the  recession  of  the  ice  seems  to  have  reached  from 
Lake  Traverse  to  the  Sheyenne  River,  and  its  level  appears  to  have  been 
then  nearly  that  of  the  general  surface  and  the  top  of  the  bluffs  bordering 
Lake  Traverse.  An  explanation  of  the  conditions  probably  producing  this 
Milnor  stage  of  the  incipient  glacial  lake,  with  the  reasons  why  it  was 
limited  to  a  comparatively  short  extent  on  the  southwestern  border  of  the 
lake  area,  has  been  presented  on  pages  150  and  211. 


312  THE  GLACIAL  LAKE  AGASSIZ. 

FROM    MILNOR    NORTH   TO    SHELDON. 

(PLATE  XXVII.) 

The  highest  level  of  Lake  Agassiz  near  Milnor  is  marked  by  the  Milnor 
beach,  already  mentioned,  where  it  is  crossed  by  the  railroad.  This  beach 
is  fine  clayey  sand,  in  somewhat  irregular  and  inteiTupted  low  ridges  and 
terraces,  abutting  at  the  west  on  undulating  till,  which  gradually  rises  10 
or  20  feet  higher,  while  on  the  east  a  descent  of  10  or  15  feet  within  about 
20  rods  is  succeeded  by  a  flat  area,  which  thence  sinks  very  slowly  north- 
eastward. The  elevation  of  the  Milnor  beach  at  the  railroad  is  1,086  feet, 
and  at  Mr.  Gr.  V.  Dawson's  house,  at  the  middle  of  the  east  side  of  section 
22,  township  133,  range  64,  1,092  feet.  Its  course  between  these  points  is 
north-northwest,  and  this  is  continued  to  the  mouth  of  a  former  channel  of 
the  Sheyenne  River,  near  the  center  of  section  4  in  this  township,  3  miles 
east  from  the  most  southern  bend  of  the  river. 

During  all  the  stages  of  Lake  Agassiz  the  Sheyenne  River  brought 
into  it  much  sediment,  carrying  the  clay  farther  than  the  sand  and  gravel, 
which  were  laid  down  near  the  river's  mouth.  Extensive  areas  of  these 
originally  flat  beds  have  been  changed  by  wind  action  to  irregular  groups 
and  belts  of  sand  hills  or  dunes,  which  vary  from  a  few  feet  to  more  than 
100  feet  in  height  above  the  surrounding  level.  Besides  the  large  tract  of 
these  dunes  before  described  east  of  the  Sheyenne  River,  others  of  even 
greater  extent  and  equally  conspicuous  border  the  river  and  reach  2  or  3 
miles  from  it  in  the  northeast  part  of  township  135,  range  54,  and  along  its 
next  15  miles. 

Watercourses  formerly  occupied  by  this  stream  are  found  west  of  the 
Milnor  beach.  One  of  them  is  marked  by  a  sandy  flat,  which  reaches 
from  the  present  course  of  the  Sheyenne  River,  in  section  1,  township  133, 
range  55,  southeastward  through  township  133,  range  54,  to  the  vicinity 
of  Milnor.  Another  runs  from  near  the  middle  of  the  southwest  quarter  of 
section  32,  township  134,  range  54,  about  1{  miles  east- southeast  to  the 
middle  of  section  4,  township  133,  range  54.  This  is  a  channel  30  to  50 
rods  wide,  about  40  feet  below  a  ridge  of  coarse  gravel,  which  extends 
along  its  northeast  side,  dividing  it  from  the  lower  area  that  was  covered 
by  Lake  Agassiz  and  from  the  present  valley  of  the  river.     The  crest  of  the 


THE  MILNOE  AND  HERMAN  BEACHES.  313 

ridge  is  nearly  flat  upon  a  width  oi  10  to  30  rods,  and  is  75  to  100  feet 
above  the  river,  being  highest  westward.  It  contains  pebbles  and  cobbles 
of  all  sizes  up  to  6  inches  in  diameter,  about  half  being  limestone  and 
nearly  all  the  others  granitic.  This  ridge  or  plateau  of  gravel  is  a  remnant 
of  an  old  delta  plain  of  the  Sheyenne  River,  apparently  deposited  before 
the  formation  of  the  Milnor  beach,  above  which  it  rises  some  40  or  50  feet, 
which  suggests  that  the  deserted  channel  of  that  depth  on  its  south  side 
was  probably  eroded  during  the  Milnor  stage  of  Lake  Agassiz.  Similar 
gravel  occurs  on  the  side  and  verge  of  the  bluff,  100  feet  high,  northwest 
of  the  Sheyenne  River,  in  the  southwest  quarter  of  section  29,  township 
134,  range  54,  but  a  rolling  surface  of  till  extends  thence  northwest. 

The  height  of  the  Sheyenne  River  in  section  32,  township  134,  range 
54,  is  1,039  feet  above  the  sea;  and  on  the  west  line  of  the  northwest 
quarter  of  section  29,  township  135,  range  54,  1,021  feet.  Its  bed  through 
these  townships  is  mostly  4  to  6  rods  wide,  with  water  1  to  2  or  3  feet 
deep,  and  is  strewn  in  many  places  with  cobbles  and  bowlders  up  to  2  or  3 
feet  and  rarely  6  or  8  feet  in  diameter.  Its  bottom  land  near  the  south 
bend,  about  a  third  of  a  mile  wide,  is  15  or  20  feet  above  the  ordinary  low 
stage  of  water,  and  during  a  term  of  fourteen  years  preceding  this  survey 
in  1885  it  had  not  been  overflowed;  but  driftwood,  found  by  the  first 
immigrants,  proves  that  the  river  sometimes  reaches  this  height.  Bluff's 
of  till  here,  in  the  southwest  corner  of  township  134,  range  54,  rise  100  to 
125  feet  above  the  stream. 

Bluffs  of  till  close  west  of  the  Sheyenne  River,  in  section  20,  township 
134,  range  54,  1,100  to  1,110  feet;  moderately  rolling  till  a  quarter  of  a 
mile  farther  west,  1,115  to  1,125  feet;  same  in  sections  17  and  18,  1,090  to 
1,130  feet;  and  on  the  east  side  of  the  river,  in  sections  21,  16,  and  17, 
1,085  to  1,075  feet,  descending  northeastward.  Prominent  swell  of  till 
west  of  the  Sheyenne  River,  in  the  southeast  quarter  of  section  30,  town- 
ship 135,  range  54,  having  four  aboriginal  mounds  on  its  crest,  1,113  feet; 
top  of  these  mounds,  1,117  feet,  very  nearly.  Highest  portions  of  the  area 
of  undulating  till  seen  westward  from  this  section  30,  3  or  4  miles  distant, 
1,125  to  1,150  feet. 


314  THE  GLACIAL  LAKE  AGASSIZ. 

Surface  at  Chai-les  G.  Froemke's  house,  in  the  northwest  quarter  of 
section  29,  township  135,  range  54,  1,075  feet;  bottom  land  of  the  Shey- 
enne  River  close  west,  1,039  to  1,029  feet;  ordinary  low  water  of  the 
river,  1,021  feet. 

Portion  of  area  of  Lake  Agassiz,  a  strip  a  fourth  to  a  third  of  a  mile 
wide,  west  of  the  Sheyenne  River,  in  sections  32  and  6,  a  half  mile  to  2 
miles  south  of  Mr.  Froemke's,  1,065  to  1,075  feet.  Herman  beach  one- 
fourth  to  two-thirds  of  a  mile  east  of  the  Sheyenne  River  here  and  extend- 
ing southeasterly  toward  the  western  limit  of  dunes  in  the  east  part  of 
township  134,  range  54,  1,073  to  1,079  feet.  Crest  of  this  beach,  a  low 
ridge  of  sand  and  fine  gravel,  at  J.  Altmann's  house,  near  the  middle  of 
section  20,  township  135,  range  54,  1,073  feet.  Within  10  or  15  rods  east 
there  is  a  descent  of  about  10  feet.  This  beach  ridge  runs  north  and 
northeasterly  to  near  the  northeast  corner  of  this  section  20,  and  thence  it 
passes  eastward  about  3  miles,  having  an  elevation  of  1,075  to  1,065  feet 
to  where  it  is  intersected  by  the  Sheyenne  River,  near  the  northeast  corner 
of  section  14.  North  of  the  river  it  continues  about  a  half  mile  in  section 
12,  its  elevation  being  1,065  to  1,070  feet,  to  the  west  end  of  a  tract  of 
dunes  25  to  100  feet  above  their  vicinity,  with  summits  at  1,100  to  1.150 
feet,  which  extends  thence  about  15  miles  eastward.  This  Herman  beach 
was  sufficient  to  turn  the  course  of  the  Sheyenne  River  along  its  west  and 
north  side  for  a  distance  of  8  miles,  from  section  9,  township  134,  range  54, 
north  and  east  to  section  14,  township  135,  range  54,  though  it  is  only  a 
ridge  of  sand  and  gravel  5  to  10  feet  higher  than  the  smoothed  area  of  till, 
occasionally  covered  hj  1  to  3  feet  of  sand,  which  lies  west  of  it  and  in 
which  the  river  has  now  cut  its  channel  50  to  60  feet  deep. 

Rolling  surface  of  till  in  the  south  edge  of  section  9,  township  135, 
range  54,  25  to  40  rods  north  of  the  Sheyenne  River,  1,080  to  1,090  feet. 
Most  of  this  section  9  is  nearly  level  till  at  1,080  to  1,085  feet,  with  occa- 
sional large  hollows  20  feet  lower.  It  seems  to  have  been  smoothed  by 
Lake  Agassiz  at  the  time  of  the  Milnor  beach.  Westward  is  slightly  undu- 
lating till,  having  an  elevation  of  1,085  to  1,125  feet  for  2  or  3  miles,  as  fai- 
as  the  si;rface  lies  within  view. 


THE  SHBYENNE  DELTA,  315 

Herman  beach  in  the  noi'thwest  quarter  of  section  10,  township  135, 
range  54,  1,075  to  1,080  feet.  This  is  a  deposit  of  gravel  and  sand 
extending  along  the  verge  of  the  plateau  of  till  just  described  in  section  9. 
Fifteen  or  20  rods  to  the  east  the  elevation  is  1,065  feet,  and  it  sinks  slowly 
thence  eastward  to  about  1,050  feet  at  the  west  base  of  the  dunes  in  sections 
12  and  1  of  this  township. 

Lakelet  back  of  this  beach,  situated  in  the  east  edge  of  the  southeast 
quarter  of  section  4,  township  135,  range  54,  about  50  rods  long  from  south 
to  north,  1,060  feet,  being  25  feet  below  the  average  of  the  adjacent 
undulating  till.  Shallow  lakelet  40  rods  across,  close  east  of  the  beach,  a 
quarter  of  a  mile  east  from  the  northwest  corner  of  section  3,  also  1,0G0 
feet;  adjoining  land,  1,065  to  1,070  feet,  excepting  on  the  west,  where  the 
Herman  beach  has  an  elevation  of  1,080  feet,  with  undulating  till  beyond 
it  a  few  feet  higher. 

Herman  beach  at  the  middle  of  the  west  side  of  section  34,  township 
136,  range  54,  Sheldon,  1,082  feet;  surface  25  rods  east,  1,070  feet,  thence 
descending  slowly  eastward.  Here  and  for  1 J  miles  south,  through  section 
3,  this  beach  is  a  flattened  ridge  of  sand  and  fine  gravel,  25  or  30  rods  wide, 
with  a  depression  3  to  .6  feet  deep  along  its  west  side.  In  the  northwest 
quarter  of  section  28  its  elevation  is  1,080  feet. 

Fargo  and  Southwestern  Railroad  track  at  Sheldon,  1,080  feet.  Wells 
in  Sheldon  village  are  10  to  15  feet  deep;  in  sandy  clay,  free  from  gravel 
or  bowlders,  6  to  10  feet,  with  sand  below.  These  deposits  belong  to  the 
Herman  beach,  which  is  here  spread  upon  a  width  of  about  a  half  mile. 

DELTA    OF    THE    SHEYENNE    RIVER. 

(PLATE   XXVII.) 

The  delta  deposited  by  the  Sheyenne  River  in  Lake  Agassiz  reaches 
from  the  Lightnings  Nest  50  miles  northwest  to  the  south  bend  of  the  Maple 
River,  and  has  a  maximum  width  of  nearly  30  miles  to  the  northeast  from 
the  south  bend  of  the  Sheyenne.  It  probably  covers  an  area  of  800  square 
miles  to  an  average  depth  of  40  feet,  its  voluijne  being,  therefore,  about  6 
cubic  miles.  Large  tracts  of  this  delta  are  channeled  ])}•  the  winds  and 
heaped  up  in  dunes,  as  before  noted,  which  rise  to  heights  of  25  to  100  feet 


316 


THE  GLACIAL  LAKE  AGASSIZ. 


or  more  above  the  average  height  of  its  expanse.     Fig.  13  presents  a  section 
crossinar  this  delta  from  east  to  west. 

The  deposition  of  the  delta  proper,  and  also  of  the  fine  lacustrine  silt 
extending  beyond  its  plateau  to  the  Red  River,  took  place  mainly  during 
the  upper  Herman  stages.  The  plateau,  gently  descending  eastward,  is 
crossed  by  the  Herman  and  Norcross  shore-lines,  and  in  part  by  the  Tintah 
and  Campbell  shores  on  its  eastern  and  southeastern  border.  From  the 
Maple  River  8  miles  east  to  Leonard,  however,  and  thence  southeasterly 
about  25  miles,  its  margin  has  been  eroded  and  changed  to  an  abrupt 
escarpment,  or  at  least  a  somewhat  steep  slope,  by  the  lake  waves  during 
the  Tintah,  Campbell,  and  McCauleyville  stages.  This  front  of  tlie  delta, 
75  to  25  feet  above  the  flat  low  land  of  the  Red  River  Valley  adjoining  its 
base,  decreases  in  prominence  as  it  is  followed  southward.     It  passes  close 


Soo 


FlQ.  13.— Section  across  the  delta  of  the  Sheyenno  Tdver.     Horizontal  scale,  6  miles  to  an  iuih. 


north  of  Leonard  and  within  a  few  miles  west  of  Kindred,  Walcott,  Colfax, 
and  Barrett,  gradually  ceasing  as  a  notable  feature  farther  south. 

A  great  portion,  probably  exceeding  a  half,  of  the  Sheyenne  delta,  as 
of  all  the  other  large  deltas  of  this  glacial  lake,  is  modified  drift,  which 
was  brought  down  by  glacial  streams  from  the  melting  surface  of  the  ice- 
sheet.  The  coarser  gravel  and  much  sand  that  were  supplied  from  the 
ice  to  the  head  streams  of  the  Sheyenne  during  the  time  of  formation  of 
its  delta  were  deposited  along  the  outer  side  of  the  great  moraines  south 
of  Devils  Lake;  the  finer  gravel  and  a  great  volume  of  sand  were  carried 
by  the  Sheyenne  to  this  delta;  and  the  finest  silt  and  clay  of  the  great 
glacial  river  were  spread  in  the  quiet  water  of  the  lake,  over  a  much  larger 
adjoining  area  of  its  bed,  from  near  Breckenridge  northward  beyond  the 
mouth  of  the  Sheyenne. 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH    XXV.    PL.  XXVM. 


s  BifN  a  CO  h 


MAP  SHOWIN&  THE  GREATER  PART  OF  THE  SHPTiT^NNK  DELTA  OF    I^AIiK    AGy\>SSIZ 
AND  CONTIGUOUS    BEACHES,   NORTH   DAKOTA. 

Scale,  6  miles  to  art  iiuli. 

Moi'aillc      I i 


Lake  Aj^ea 


Delta 


AUitiules    or    7Yd/nav    stations    cti'C    iKilpd    in      f'cc^t      trho\'i'     I  tip    sen. 


THE  SHBYENNE  DELTA.  317 

Much  alluvium  was  also  supplied  from  tlie  erosion  of  the  Sheyenne 
Valley,  which,  with  that  of  the  Big  Coulee  (the  avenue  of  discharge  from 
the  glacial  Lake  Souris  to  the  Sheyenne  and  Lake  Agassiz),  probably 
averages  three-fourths  of  a  mile  in  width  and  150  feet  in  depth  along  a 
distance  of  200  miles.  This  channel  is  cut  in  the  drift  sheet,  mainly  till, 
and  in  the  underlying,  easily  eroded  Cretaceous  shales.  The  volume  of  the 
material  supplied  from  it  would  be  equal,  according  to  these  estimates, 
to  about  three-fourths  of  the  Sheyenne  delta,  or  perhaps  three-eighths  of 
both  the  delta  and  the  finer  clayey  sediments  that  were  deposited  farther 
out  in  the  lake.  But  the  valley  of  the  Sheyenne,  in  considerable  portions 
of  its  extent,  was  also  a  preglacial  valley.  If  it  retained  in  a  considerable 
degree  its  trough-like  form  beneath  the  ice-sheet,  as  was  evidently  true 
of  the  Minnesota  Valley,^  its  erosion  and  its  tribute  to  the  Sheyeime  delta 
would  be  less  than  the  proportion  estimated. 

PROM    SHELDON    NORTH    TO    THE    NORTHERN    PACIFIC    RAILROAD. 

(PLATES   XXVII   AND   XXVIII.) 

The  Herman  beach,  terrace-like,  at  Hugh  Mcintosh's  house,  in  the 
south  edge  of  the  northwest  quarter  of  section  8,  Sheldon,  has  its  crest 
1,083  to  1,084  feet  above  the  sea.  His  well,  near  the  top  of  the  beach,  22 
feet  deep,  is  soil  and  sandy  clay  to  a  depth  of  7  feet,  then  sand  15  feet  to 
water.  Till  rises  to  the  surface  20  rods  farther  west.  About  30  rods  east, 
on  land  10  feet  lower,  a  well  10  feet  deep  is  all  caving  sand  below  the  black 
soil,  which  is  1  or  2  feet  deep. 

Maple  River  in  section  32,  Highland,  about  2  miles  northeast  from  its 
most  southern  bend,  1,019  feet.  It  is  20  to  40  feet  wide  and  1  to  3  feet 
deep,  with  cobbles  and  bowlders  in  many  portions  of  its  channel.  Herman 
beach,  a  sand  and  gravel  deposit,  extending  a  quarter  of  a  mile  from  south 
to  north  on  the  verge  of  the  bluff  of  till  west  of  Maple  River  in  the  north- 
west part  of  this  section  22,  1,072  to  1,077  feet.  In  the  north  edge  of  the 
northwest  quarter  of  this  section,  the  northeast  corner  of  section  31,  and 
the  east  edge  of  section  30,  it  is  a  plateau-like  tract  a  fourth  of  a  mile  wide, 
with  a  subsoil  of  sand  and  fine  gravel,  1,086  feet,  from  which  both  east  and 

I  "The  Minnesota  Valley  in  the  Ice  age,"  Proc,  A.  A.  A.  S.,  Vol.  XXXII,  for  1883,  pp.  213-231. 
Geology  of  Minnesota,  Vol.  I,  1884,  pp.  479-485,581;  Vol.  II,  1888,  p.  134. 


318  ■         THE  GLACIAL  LAKE  AGASSIZ. 

west  a  gentle  slope  falls  5  feet  within  20  or  3(^  rods.  In  the  northwest 
quarter  of  section  20  and  the  west  half  of  section  17,  Highland,  it  is  a 
gracefully  rounded  ridge,  1,085  to  1,087  feet,  with  descent  of  about  5  feet 
on  its  west  side  and  10  to  15  feet  within  as  many  rods  on  the  east.  The 
surface  east  of  the  Maple  River  in  this  township  has  an  elevation  of  1,075 
to  1,065  feet,  declining  toward  the  north  and  east.  In  the  east  half  of 
Pontiac,  the  next  township  on  the  west,  a  surface  of  till,  moderately  undu- 
lating near  the  beach  of  Lake  Agassiz,  but  prominently  rolling  at  a  distance 
of  3  miles  to  the  west,  rises  to  1,150  and  1,175  feet  in  the  vicinity  of  the 
Maple  River  above  its  south  bend. 

The  Herman  beach,  a  broad,  flattened  ridge  of  sand  and  gravel,  passes 
in  a  north-northeast  course  through  the  center  of  section  8,  Highland,  its 
elevation  being  1,083  feet.  A  smoothed  surface  of  till,  1,082  to  1,087  feet, 
with  occasional  sloughs  in  depressions  15  to  20  feet  deep,  occupies  the  west 
half  of  this  section  8  ;  and  close  east  of  the  beach  a  flat  of  till  on  the  east 
line  of  the  section,  at  1,065  to  1,070  feet,  was  the  bed  of  the  lake. 

Continuing  northeastward,  the  beach  is  offset  a  mile  to  the  east,  in 
sections  4  and  3,  Highland,  so  that  the  greater  part  of  section  4  was  a  bay 
of  Lake  Agassiz  during  its  Herman  stage,  with  bottom  at  1,080  to  1,065 
feet,  inclosed  on  the  west,  north,  and  east  by  beach  deposits.  The  highest 
portion  of  the  hook  or  spit  east  of  this  bay  is  in  the  southwest  quarter  of 
section  3,  1,093  to  1,096  feet.  It  is  composed  of  sand  and  fine  gravel, 
with  pebbles  mostly  less  than  an  inch,  but  occasionally  2  inches  in  diameter, 
forming  a  smoothly  rounded  swell  30  to  40  rods  wide.  This  cape,  project- 
ino-  south  and  west  a  mile  into  the  lake,  was  accumulated  by  the  southward 
drift  of  the  beach  material  along  the  shore,  caused  by  northern  winds,  as 
is  also  observable  at  various  other  places  on  both  the  east  and  west  shores 
of  this  glacial  lake  and  on  both  sides  of  Lake  Michigan  at  the  present  time. 

Herman  beach  in  the  west  edge  of  section  26,  Eldred,  1,094  feet.  On 
the  east  side  of  the  beach  here,  near  the  center  of  this  section,  is  a  slough 
filled  with  rushes  and  containing  water  all  the  year ;  its  elevation  is  about 
1,065  feet,  that  of  the  land  on  its  east  side,  in  the  east  part  of  this  section, 
being  about  1,075  feet.  In  the  northeast  quarter  of  section  34  the  beach 
is  intersected  by  a  sluggish  creek,  apparently  formed  by  springs  within  a 


THE  UPPER  OE  HERMAN  BEACHES.  319 

half  mile  northwest,  its  ravine  being  fully  40  feet  below  the  general  level 
of  the  beach  and  the  laud  westward.  Again,  in  the  southwest  quarter  of 
section  26  the  beach  is  cut  by  a  dry  channel,  the  outlet  in  rainy  weather 
from  a  small  slough. 

Through  the  west  half  of  section  23,  Eldred,  the  beach  is  a  low, 
smoothly  rounded  ridge  of  sand  and  fine  gravel,  about  half  of  which  is 
limestone  and  the  rest  granite  or  other  Archean  rocks.  As  in  the  3  miles 
next  southward,  it  is  largely  composed  of  fine  gravel,  and  pebbles  abound, 
often  covering  half  the  surface  of  the  knolls  made  by  gophers.  Most  of  the 
pebbles  are  less  than  an  inch  in  diameter,  but  some  measure.  2  and  a  few 
3  inches.  The  elevation  of  this  beach  ridge  is  1,092  to  1,100  feet;  on  the 
north  line  of  this  section  its  height  is  1,099  feet.  A  broad  depression  3  to 
5  feet  below  the  beach  borders  its  west  side.  Toward  the  east  there  is  a 
descent  of  about  10  feet  in  25  or  30  rods,  and  thence  a  gradual  slope  sinks 
to  1,060  or  1,050  feet  within  1  to  IJ  miles. 

Undulating  tdl  in  sections  22  and  15,  Eldred,  1,095  to  1,110  feet;  crests 
of  prominently  rolling  till  in  the  west  edge  of  section  11  and  the  south 
part  of  section  10,  1,115  to  1,125  feet;  thence  northwestward  lower  undu- 
lating till  has  an  elevation  of  only  1,090  to  1,100  feet  for  nearly  2  miles, 
and  rises  quite  slowly  beyond.  This  somewhat  irregular  contour  has 
caused  considerable  diversity  in  the  development  of  the  beach,  so  that  its 
deposits  are  massed  in  unusual  amount  in  some  places,  while  elsewhere 
they  are  deficient  or  wholly  wanting.  In  the  southwest  quarter  of  the 
southwest  quai'ter  of  section  14,  Eldred,  a  swell  of  gravel,  with  pebbles  up 
to  2  inches  or  rarely  3  inches  in  diameter,  rises  to  1,105  feet,  extending- 
about  40  rods  from  south  to  north;  and  similar  gravel,  at  1,095  to  1,105 
feet,  occurs  in  the  west  part  of  the  northwest  quarter  of  section  23,  west  of 
the  distinct  beach  ridge.  The  northwest  part  of  section  1 4  is  a  nearly  flat 
tract,  having  a  subsoil  of  sand  and  fine  gravel,  with  an  elevation  of  1,090 
to  1,095  feet.  A  beach  ridge  extending  south  from  the  east  side  of  a  prom- 
inent swell  of  till  in  the  southwest  quarter  of  section  11,  at  1,086  to  1,089 
feet,  has  a  continuous  depression  of  about  5  feet  on  its  west  side  and  is  bor- 
dered eastward  by  land  6  to  10  feet  below  its  crest.  In  the  northwest  part, 
of  this  section  11  and  the  southeast  part  of  section  3  the  shore  of  Lake 


320  THE  GLACIAL  LAKE  AGASSIZ. 

Agassiz  is  marked  by  slight  erosion  in  the  rolhng  and  undulating-  surface  of 
till  rather  than  bv  the  usual  beach  denosits  of  travel  and  sand. 

*/  J.  o 

Beyond  this,  a  conspicuous  beach  ridge  25  to  40  rods  wide,  elevated 
10  feet  above  the  undulating  till  on  its  west  side  and  Ijordered  by  a  still 
lower  surface  on  the  east,  extends  from  the  middle  of  the  southwest  quarter 
of  the  southeast  quarter  of  section  3,  Eldi'ed,  northwestward  to  near  the 
middle  of  the  north  line  of  the  northwest  quarter  of  this  section,  where  it 
is  interrupted  by  a  drainage  gap  about  20  feet  below  its  crest.  Thence  this 
massive  beach  ridge  continues  in  a  north-northeast  course  tlu'ough  section 
34,  Howes,  to  near  the  middle  of  its  north  line.  Its  material  is  sand  and 
gravel,  with  pebbles  up  to  1  ^  inches  in  diameter.  In  section  3  its  elevation 
is  1,095  to  1,090  feet,  and  in  section  34,  1,089  to  1,094  feet.  It  passes 
onward  as  a  very  distinct  and  typical  beach  ridge,  with  the  same  north- 
northeast  course,  through  sections  27  and  22,  Howes,  having  an  elevation 
of  1,087  to  1,095  feet  in  section  27  and  1,089  to  1,096  feet  in  section  22. 
Its  eastern  slope  in  these  sections  descends  15  to  20  feet. 

About  a  half  mile  west  from  this  great  beach  ridge  the  east  edge  of 
section  4  has  irregular  deposits  of  beach  gravel  and  sand  in  swells  and  bars 
5  feet  above  the  general  level,  iind  in  the  east  edge  of  section  33,  Howes, 
a  well-defined  parallel  beach  begins,  having  a  width  of  20  to  25  rods  and 
elevation  of  1,092  to  1,094  feet,  with  a  depression  2  to  4  feet  lower  on  the 
west  and  descent  of  about  5  feet  on  the  east.  This  western  Herman  beach 
extends  as  a  continuous  ridge  2  miles  to  the  north-northeast,  excepting  a 
gap  where  it  is  intersected  by  a  small  stream  in  the  northwest  quarter  of 
section  27.  Its  material  is  sand  and  gravel,  with  pebbles  up  to  2  inches  in 
diameter,  about  half  being  limestone.  Both  tliis  and  the  east  beach  have  a 
black  soil  a  foot  or  more  in  depth,  and  are  scarcely  inferior  to  the  adjoining 
areas  of  till  in  productiveness.  Farther  west  a  slightly  undulating  or 
nearly  flat  surface  of  till  extends  from  a  half  mile  to  1^  miles  before  it 
rises  above  1,095  feet,  and  the  highest  of  its  swells,  seen  3  to  6  miles  away 
to  the  west  and  northwest,  do  not  exceed  1,150  or  1,175  feet.  The  western 
Herman  beach  on  the  north  line  of  the  northwest  quarter  of  section  27  has 
a  height  of  1,095  feet;  about  6  rods  to  the  south,  1,097  feet;  and  northeast- 


THE  UPPEE  OR  HERMAI^r  BEACHES.  321 

ward,  ill  section  22,  1,092  to  1,095  feet,  to  its  junction  with  the  eastern  or 
main  beach  in  the  east  part  of  this  section. 

A  lower  Herman  beach,  formed  after  the  lake  level  here  had  fallen 
slightly,  appears  in  the  northwest  edge  of  section  26,  Howes,  having  its 
crest  at  1,072  to  1,075  feet;  passing  north-northeastward  through  the  west 
half  of  section  23,  its  elevation  is  1,075  to  1,080  feet;  through  section  14, 
1,080  to  1,087  feet,  being  highest  near  the  center  of  this  section;  and  in 
the  east  part  of  sections  11  and  2  and  onward  to  the  southwest  quarter  of 
section  36,  Buffalo,  1,083  to  1,080  and  1,075  feet.  Its  maximum  develop- 
ment is  in  section  14,  where  it  is  a  massive,  smoothly  rounded  ridge  of  sand 
and  fine  gravel,  30  rods  wide,  with  a  descent  of  15  feet  on  each  side.  In 
sections  26  and  23  it  is  bordered  on  the  west  by  a  continuous  depression  4 
to  8  feet  below  it;  and  through  sections  14,  11,  and  2,  and  in  the  southwest 
quarter  of  section  36,  a  slough  3^  miles  long,  mown  for  its  luxuriant  marsh 
hay,  having  an  elevation  of  1,067  to  1,072  feet,  lies  between  this  and  the 
main  beach,  a  half  mile  farther  west. 

Floor  of  S.  P.  Gardner's  house,  in  the  northwest  corner  of  section  27, 
Howes,  1,096  feet. 

Main  Herman  beach  through  the  west  edge  of  section  14,  Howes, 
1,096  to  1,093  feet,  declining  northward;  in  the  west  part  of  section  11, 
1,093  to  1,095  feet;  in  section  2,  1,092  to  1,095  feet,  changing  from  a  north 
to  a  north-northeast  course;  in  the  southeast  edge  of  section  35  and  the 
northwest  edge  of  section  36,  Buffalo,  1,092  to  1,096  feet;  and  in  the  west 
part  of  section  25,  where  it  is  cut  by  the  Northern  Pacific  Railroad,  1,095 
to  1,101  feet.  At  the  railroad  cut  its  crest  is  1,099  to  1,101  feet,  and  the 
track  is  1,092  feet  above  the  sea.  Along  this  distance  of  5  miles  it  is  a 
typical  beach  ridge  of  sand  and  gravel,  with  pebbles  up  to  2  inches  and 
occasionally  3  to  6  inches  in  diameter,  about  30  rods  wide,  rising  nearly  25 
feet  above  the  slough  on  the  east,  and  bordered  on  the  west  by  a  continu- 
ous depression,  mostly  about  an  eighth  of  a  mile  wide,  3  to  7  feet  below  its 
crest.  Slightly  undulating  till  rises  beyond  to  1,125  and  1,140  feet  within 
1  or  1 J  miles  west,  which  is  as  far  as  the  surface  lies  within  view. 

Northern  Pacific  Railroad  track  at  Wheatland,  993  feet;  on  bridge 
over  creek  in  the  east  edge  of  section  25,  Buffalo,  4  miles  west  of  Wheat- 

MON  XXV 21 


322  THE  GLACIAL  LAKE  AGASSIZ. 

land  and  three-fifths  of  a  mile  east  of  the  Herman  beach,  1,076  feet;  bed 
of  the  creek,  1,057  feet;  track  at  summit,  4^  miles  west  from  the  Herman 
beach,  same  as  the  natural  surface,  1,208  feet;  and  at  Buffalo,  a  half  mile 
farther  west,  1,202  feet. 

FKOM   THE    NORTHERN    PACIFIC    RAILROAD    NORTH    TO    GALESBURG. 

(PLATE   XXVIII.) 

The  Herman  beach,  a  broad,  smoothly  rounded,  continuous  ridge  of 
the  same  material  and  contour  as  southward,  runs  to  the  north-northeast  for 
the  next  4  miles  north  from  the  Northern  Pacific  Railroad,  with  its  crest  at 
1,097  to  1,100  feet,  very  constant  in  elevation.  The  descent  of  its  east 
slope  is  15  or  20  feet  in  about  20  rods,  and  of  its  west  slope  about  5  feet. 
Thence  Avestward  the  surface  is  undulating  till,  in  swells  10  to  15  feet  above 
the  depressions,  rising  gradually  to  1,150  and  1,200  feet  above  the  sea  at  a 
distance  of  3  to  5  miles,  the  farthest  seen  in  that  direction.  In  a  broad 
view  this  area  seems  an  almost  flat  j)lain. 

Where  this  beach  is  cut  by  the  branch  of  the  Great  Northern  Railway 
from  Ripon  to  Hope,  near  the  middle  of  the  line  between  sections  32  and 
33,  Empire,  its  crest  was  1,096  to  1,099  feet  above  the  sea.  It  has  been 
excavated  here  for  ballast  to  a  distance  of  about  30  rods  south  from  the 
railway.  It  is  mostly  gravel ;  the  pebbles  seldom  exceed  2  inches  in  diam- 
eter; about  half  is  limestone,  and  the  remainder  granitic.  The  thickness  of 
this  beach  deposit  is  only  8  to  10  feet;  its  east  slope  falls  12  or  15  feet,  and 
its  west  slope  5  to  7  feet. 

On  the  floor  of  this  excavation,  about  10  rods  south  from  the  railway, 
in  the  upper  foot  of  the  till  or  bowlder-clay,  under  the  gravel,  numerous 
bones  of  a  mammoth  were  found  in  the  year  1884.  These  included  a  tusk 
11  feet  long  and  9  inches  in  diameter  (tapering  to  6  inches  at  the  smaller 
end,  where  it  was  broken  off),  three  teeth,  two  vertebrae,  and  several  other 
bones.  They  were  embedded  in  the  top  of  the  till,  and  the  overlying  beach 
formation  has  yielded  no  bones,  shells,  or  other  fossils. 

Southward  from  this  locality  the  Hennan  beach  is  double  for  a  dis- 
tance of  about  4  miles.  The  secondary  beach  ridge  east  of  that  already 
described  is  similar  in  size  and  material.     Its  south  end  is  in  the  west  part 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.    XXVIII. 


MAP  OF  THK  WKSlliRN  HHOKES  OF  I^KK  AGASSIZ.FKOM   THE  VICINriY   OF   \VHi-:An^NL), 

CASS  COUNTY, NORTH  TO  P0R'JX/\N1)  AND  MAYVH.LE/mAlLJ.  COUINTIXNORTH  UiU^OTA. 

Scale,  (i  nijlcs  Lo  ;ui  inch  

Lake  Area  i Ll  Delia  ! J 

Altitudes    of   railway    stations     are      noted   in    /'eel      adotv     the    sea . 


THE  UPPEB  OR  HEEMAI^  BEACHES.  323 

of  section  19,  Wheatland,  a  half  mile  east  from  the  main  beach,  and  it 
passes  thence  north-northeastward  through  sections  18,  7,  and  the  east 
edge  of  section  6,  having  an  elevation  of  1,081  to  1,084  feet.  It  becomes 
merged  with  the  main  beach  in  the  southeast  quarter  of  section  32,  Empire. 
Between  these  beach  ridges  is  a  depression,  approximately  1,075  feet,  partly 
occupied  by  a  grassy  slough,  which  is  all  used  as  mowing  land,  having  no 
area  of  water  or  bog. 

The  Herman  beach  in  the  southwest  quarter  of  section  28,  Empire,  at 
a  height  of  1,094  to  1,096  feet,  is  not  so  distinct  as  usual,  being  intersected 
by  Swan  Creek  and  having  no  well-marked  depression  along  its  west  side. 
Farther  north  in  this  section  it  is  a  ridge  of  the  ordinary  type,  with  its 
crest  at  1,096  to  1,098  feet.  In  section  21  it  is  narrowed  to  8  or  10  rods 
in  width,  but  continues  as  a  very  distinct  ridge  with  a  slight  ascent  north- 
ward, from  1,097  to  1,101  feet.  Its  east  slope  falls  15  to  20  feet  in  about 
20  rods,  and  there  is  a  depression  of  3  to  6  feet  on  the  west.  Thence  a 
surface  of  undulating  till,  seeming  nearly  flat  in  a  general  view,  rises  gradu- 
ally westward  to  about  1,150  feet  at  a  distance  of  2  or  3  miles. 

This  beach  ridge  passes  onward  through  section  16  and  the  south  part 
of  section  9,  Empire,  with  an  elevation  of  1,095  to  1,100  feet;  but,  having 
been  followed  thus  continuously  in  a  north-northeast  course  for  more  than 
15  miles,  it  ceases  in  the  east  part  of  this  section  9.  Its  north  end  abuts  at 
1,100  to  1,105  feet  upon  a  terrace  slope  of  till,  which  rises  about  10  feet 
higher.  This  forms  the  east  boundary  of  a  slightly  undulating  expanse  of 
till,  which  thence  gradually  rises  to  1,150  and  1,200  feet  in  2  to  5  miles 
west  and  northwest.  From  section  9  northward  through  the  east  part  of 
section  4,  and  in  the  west  edge  of  section  34  and  the  west  part  of  sections 
27,  22,  and  15,  Erie,  passing  close  east  of  Erie  railway  station,  the  Her- 
man shore  of  Lake  Agassiz  is  marked  by  such  a  terrace  or  escarpment 
formed  by  wave  erosion,  and  the  usual  deposit  of  beach  gravel  and  sand  is 
absent.  The  base  of  the  escarpment  is  at  1,095  feet,  approximately,  and  it 
rises  with  a  moderate  slope  25  to  40  feet. 

About  a  half  mile  east  of  this  escarpment,  however,  lies  a  broad,  low 
ridge  of  beach  sand  and  fine  gravel,  having  an  elevation  of  1,085  to  1,090 
feet.     Its  course  is  from  the  west  part  of  section  10  north-northeast  tlu-ough 


324  THE  GLACIAL  LAKE  AGASSIZ. 

sections  3  and  34,  and  nearly  due  north  through  the  east  edge  of  sections 
27,  22,  and  15.  The  descent  eastward  is  more  gentle  than  usual,  falling 
only  6  to  10  feet  in  a  quarter  of  a  mile,  beyond  which  is  a  flat  area  of  till. 
On  the  west  a  depression  3  to  5  feet  deep,  partly  occupied  by  a  grassy 
slough,  intervenes  between  this  beach  ridge  and  the  wave-cut  escarpment. 
On  the  north  line  of  section  15  the  crest  of  the  ridge  is  at  1,092  feet;  the 
depression  west,  1,088;  the  base  of  the  escarpment,  1,092,  and  its  top, 
about  1,115  feet. 

Great  Northern  Railway  from  Ripon  to  Portland,  track  at  tank  and 
section  house  close  south  of  Rush  River,  1,094  feet;  at  Erie,  2  miles  farther 
north,  1,126  feet;  summit  about  1  mile  north  of  Erie,  1,131  feet;  South 
Branch  of  the  North  Fork  of  Elm  River,  bridge,  1,081  feet;  bed  of  creek, 
1,062  feet;  track  at  summit  1  mile  north,  1,089  feet;  at  Oalesburg,  1,079 
feet;  North  Branch  of  the  North  Fork  of  Elm  River,  bridge,  1,076  feet; 
bed  of  creek,  1,063  feet;  track  at  Clifford,  1,055  feet.  At  Erie  and  west- 
ward the  surface  is  prominently  rolling  till,  which  rises  within  3  miles  to  a 
height  of  100  feet  above  the  shore  of  Lake  Agassiz. 

In  sections  10  and  3,  Erie,  the  Herman  beach  is  again  well  exhibited 
in  its  usual  character.  On  the  north  line  of  section  10  it  is  a  gently 
rounded  ridge  of  sand  and  gravel,  with  pebbles  up  to  2  inches  and  rarely 
3  or  4  inches  in  diameter,  half  being  limestone;  its  width  is  about  20  rods; 
the  elevation  of  its  crest  is  1,106  feet,  and  the  slopes  fall  10  feet  on  the  east 
and  3  feet  on  the  west.  For  the  next  mile  northward,  through  the  west 
part  of  section  3,  this  beach  ridge  has  a  width  of  10  to  15  rods;  its  elevation 
is  mostly  1,105  to  1,108  feet,  with  a  depression  5  to  7  feet  deep  along  its 
west  side;  but  in  a  few  places  the  ridge  itself  is  depressed  to  1,099  feet. 
Passing  northward,  this  beach  in  the  west  half  of  section  34,  Dows,  is  a 
very  smooth,  gracefully  rounded,  wave-like  swell,  30  to  40  rods  wide, 
1,108  to  1,112  feet  in  elevation,  rising  15  feet  above  its  east  base  and 
having  a  depression  of  3  to  5  feet  on  the  west.  A  well  in  the  northeast 
quarter  of  the  southwest  quarter  of  section  34,  on  the  top  of  this  beach, 
went  through  12  feet  of  sand  and  gravel,  going  into  till  below.  In  the 
southwest  quarter  of  section  27  the  beach  continues  with  the  same  massive 
development  and  nearly  north  course,  its  elevation  being  1,111  to  1,115 


THE  UPPER  OR  HERMAN  BEACHES.  325 

feet.  In  the  northwest  quarter  of  this  section  it  becomes  a  still  broader 
deposit  of  gravel  and  sand,  a  fourth  to  a  third  of  a  mile  wide,  with  no 
depression  on  its  west  side.  Here  its  course  is  turned  northwestward, 
entering  the  southeast  quarter  of  section  21  with  an  elevation  of  1,109 
feet;  but  it  seems  not  to  be  distinctly  traceable  farther.  About  a  half  mile 
west  of  this  beach  a  plateau  of  till,  1,125  to  1,128  feet  above  the  sea, 
extends  a  third  of  a  mile  from  southeast  to  northwest  in  the  southeast 
quai'ter  of  section  28;  but  for  a  mile  south  and  west  of  this  plateau,  and 
for  3  miles  northwest,  the  surface  of  slightly  undulating  till  averages  only 
1,105  to  1,120  feet. 

The  secondary  Herman  beach,  already  described  in  its  course  east  of 
the  Erie  escarpment  of  till,  continues  northward  with  an  elevation  of  1,095 
feet,  approximately,  through  the  east  half  of  sections  10  and  3,  Erie,  and 
sections  34  and  27,  Dows.  In  sections  22  and  16  this  beach  turns  in  a 
gradual  curve  to  the  northwest  and  west,  and  its  crest  varies  in  height  from 
1,095  to  1,104  feet,  being  highest  in  or  near  the  southeast  corner  of  section 
16.  There  it  is  a  ridge  of  gravel  and  sand  about  30  rods  wide,  rising  10 
to  15  feet  above  its  northeastern  base  and  descending  6  to  10  feet  on  the 
southwest  to  a  nearly  flat  tract  of  moist  mowing  land  fully  a  mile  wide, 
with  a  height  of  1,090  to  1,095  feet.  Through  sections  17,  8,  and  5  it 
again  curves  to  the  northwest,  north,  and  north-northeast,  ha^dng  an  eleva- 
tion of  aliout  1,095  feet.  In  the  north  half  of  sections  5  and  4,  Dows,  a 
smooth  plain  with  sand  subsoil  extends  a  mile  eastward  from  the  east  base 
of  this  beach  ridge,  descending  in  this  distance  from  1,090  to  1,075  feet. 

Continuation  of  this  beach  northward  nearly  through  the  middle  of 
section  32,  Galesburg,  1,096  to  1,099  feet.  It  is  a  typical  beach  ridge  of 
fine  gravel  and  sand,  8  to  10  feet  above  the  land  on  its  east  side  and  having 
a  descent  of  about  5  feet  westward,  beyond  which  the  surface  of  undulat- 
ing till  rises  in  1  orl^  miles  to  1,125  feet  and  in  the  next  2  miles  to  1,175. 
or  1,200  feet.  A  half  mile  east  from  this  beach,  and  only  20  to  30  rods 
west  of  the  railroad,  there  is  a  parallel  beach  ridge  of  similar  size  and 
material,  at  1,090  to  1,092  feet.  The  former  of  these  beaches,  where  it 
crosses  the  south  line  of  section  20,  a  fourth  to  a  half  mile  west  of  Galesburg, 
is  spread  in  a  broad,  nearly  flat  deposit  which  rises  westward  from  1,096  to 
1,101  feet.     On  the  west  it  is  bordered  by  a  depression  about  8  feet  lower. 


326  THE  GLACIAL  LAKE  AGASSIZ. 

FROM    GALESBURG   NORTH   TO    LARIMORE. 

(PLATES   XXVIII   AND   XXIX.) 

In  section  20,  Galesburg,  the  beach  is  about  a  third  of  a  mile  wide, 
its  higher  western  margin  being  at  1,097  to  1,102  feet.  From  its  crest  a 
slope  descends  first  somewhat  steeply  and  then  slowly  to  the  amount  of  20 
or  25  feet  in  two-thirds  of  a  mile  eastward,  having  a  subsoil  of  sand  and 
very  fine  gi-avel  to  a  depth  of  5  to  10  feet,  imderlain  by  till,  as  is  shown  by 
wells  at  Galesburg.  Crest  of  this  beach  through  the  west  half  of  section 
17,  1,102  to  1,107  feet;  in  section  6,  Galesburg,  and  in  sections  32  and  29, 
Norman,  1,115  to  1,125  feet,  being  10  to  15  feet  higher  than  on  the  south 
and  north;  in  sections  20  and  17,  about  1,110  feet;  in  the  southwest  part 
of  section  8,  1,117  feet;  westward  through  section  7  of  this  township,  and 
tlu'ough  the  northeast  part  of  section  12,  township  145,  range  54,  1,112  to 
1,117  feet.  On  the  line  between  Traill  and  Steele  counties,  where  the  top 
of  the  ridge  is  at  1,114  feet,  it  is  a  typical  beach  deposit  about  25  rods 
wide,  composed  of  sand  and  gravel,  with  pebbles  up  to  2  or  3  inches  in 
diameter.  Its  course  is  due  west,  and  the  descent  from  crest  to  base  on  the 
south  is  6  or  8  feet,  and  northward  12  or  15  feet,  beyond  which  a  very 
gentle  slope  sinks  toward  the  northeast.  A  well  on  this  beach,  in  the  east 
edge  of  the  northwest  quarter  of  section  12,  township  145,  range  54,  went 
through  sand  and  fine  gravel  13  feet,  finding  till  below.  Within  a  few 
hundred  feet  farther  west  the  beach  is  interrupted  for  a  distance  of  about  1 
mile  by  an  area  of  till  some  15  feet  lower,  with  no  beach  deposits.  It 
reappears,  however,  as  a  typical  beach  ridge  of  gravel  and  sand  for  a  dis- 
tance of  three-fourths  of  a  mile  in  the  northwest  quarter  of  section  11  and 
the  northeast  quarter  of  section  10,  having  an  elevation  of  1,114  to  1,112 
feet,  with  a  slough  on  its  south  side  6  to  8  feet  lower. 

Returning  to  the  vicinity  of  Galesburg,  a  slightly  higher  beach,  approx- 
imately parallel  with  the  foregoing,  remains  to  be  traced.  It  becomes 
recognizable  in  the  west  edge  of  section  20,  Galesburg,  where  the  border 
of  the  area  of  rolling  till  that  extends  thence  westward  bears  occasional 
deposits  of  gravel  at  1,115  to  1,120  feet.  In  the  east  part  of  section  18  it 
is  a  well-developed  beach  ridge  of  sand  and  fine  gravel  30  to  50  rods  wide, 


THE  UPPER  OR  HERMAN  BEACHES.  327 

with  a  depression  on  the  west  4  to  6  feet  below  its  top,  which  has  an  eleva- 
tion of  1,120  to  1,123  feet.  Northward  in  section  7,  this  beach,  continuing 
at  1,120  to  1,123  feet,  is  quite  broad,  without  a  distinctly  ridged  form,  and 
is  indented  from  the  east  by  a  large  slough,  whose  elevation  is  approximately 
1,100  feet,  including  several  acres  of  water  free  from  grass  and  rushes- 
Ci-est  of  beach  in  the  southwest  quarter  of  section  6,  Galesburg,  1,122  to 
1,126  feet;  through  sections  31  and  30,  Norman,  1,125  to  1,129  feet;  and 
in  the  west  half  of  section  19,  1,127  to  1,124  feet,  sinking  slightly  from 
south  to  north.  The  farther  course  of  this  shore  is  not  marked  by  con- 
tinuous beach  deposits;  but,  following  the  contour  line  of  1,125  feet,  it 
must  turn  west  in  the  southwest  quarter  of  section  18,  Norman,  and  extend 
tlirough  sections  13  to  6,  township  145,  range  54,  to  the  South  Branch  of 
Goose  River. 

Natural  surface  at  the  southwest  corner  of  section  3,  township  145, 
range  54,  a  dozen  rods  west  of  the  South  Branch  of  Goose  River,  1,104 
feet.  This  stream,  about  1,070  feet,  is  8  to  20  feet  wide  and  mostly  1  to  2 
feet  deep.  Its  bottom  land,  5  to  10  feet  above  this  stage  of  low  water, 
varies  from  20  to  100  rods  in  width  and  is  inclosed  by  bluffs  rising  30  to 
50  feet,  increasing  in  height  southwestward.  The  valley  has  no  timber,  the 
largest  wood  growth  being  willows  5  to  8  feet  high  and  2  J  inches  or  less 
in  diameter.  With  the  aid  of  these,  however,  .beavers  had  constructed 
dams,  and  were  living  on  this  stream  when  this  survey  was  made  in  1885, 
one  of  their  dams  then  occupied  being  found  by  my  assistant,  Mr.  Robert 
H.  Young,  in  the  west  edge  of  section  10,  township  145,  range  54. 

Floor  of  Hemy  Bentley's  barn,  in  the  southwest  corner  of  the  southeast 
quarter  of  section  6,  township  145,  range  54,  on  the  Herman  shore  of  Lake 
Agassiz,  1,123  feet.  This  is  a  moderate  slope,  ascending  12  or  15  feet, 
eroded  in  till,  which  from  its  top  stretches  westward  about  2  miles  in  a 
nearly  level  expanse.  From  the  south  side  of  section  6,  such  a  low  escarp- 
ment, with  its  top  at  1,120  to  1,123  feet,  extends  due  north,  or  a  few  degrees 
west  of  north,  about  5  miles. 

E.  W.  Palmer's  house,  in  the  northwest  corner  of  the  southwest  quarter 
of  section  2,  township  145,  range  55,  1,145  feet.  Well  here,  27  feet  deep: 
soil  and  very  hard  gravel  and  sand,  2  feet;  sand  with  occasional  layei's  of 


328  THE  GLACIAL  LAKE  AGASSIZ. 

fine  gravel,  22  feet;  and  darker  clayey  quicksaud,  3  feet,  with  water.  This 
is  on  the  west  part,  nearly  at  the  crest,  of  an  nnusually  high  beach  of 
this  glacial  lake,  similar  in  elevation  with  the  Milnor  beach  farther  south. 
Including  its  slopes,  it  has  a  width  of  60  rods,  the  nearly  flat  crest  being 
40  rods  across  and  in  elevation  1,142  to  1,147  feet.  The  depression  on  the 
west  falls  about  5  feet.  In  the  north  part  of  section  2  this  sand  and  gravel 
deposit  has  an  iiTegular  contour,  not  lying  in  a  continuous  ridge ;  its  highest 
l^ortions  vary  from  1,145  to  1,152  feet.  Southward  from  section  2  it  is  not 
continuous,  but  is  inteiTupted  by  wide  depressions  where  the  surface  is  till. 
Beach  gravel  and  sand  appear,  however,  in  some  amount  at  Mr.  Thomas 
Ward's,  in  the  southwest  corner  of  section  11,  township  145,  range  55;  also 
in  the  southwest  part  of  section  23,  nearly  2  miles  fai-ther  south.  Within  1 
to  3  miles  west  from  these  sections  an  area  of  undulating  and  rolling  till 
rises  to  1,200  and  1,250  feet. 

Near  the  middle  of  the  north  half  of  section  23,  township  146,  range 
55,  the  elevation  of  this  beach  is  1,142  to  1,144  feet.  It  is  a  ridge  of  gravel 
and  sand,  extending  a  quarter  of  a  mile  from  southeast  to  northwest,  Avith 
crest  15  feet  above  the  surface  on  each  side.  Toward  the  east  it  descends 
in  a  long  slope,  but  more  steeply  westward.  In  section  14  this  shore-line 
curves  westerly,  the  crests  of  its  somewhat  irregular  beach  deposits  being 
about  1,135  feet,  with  a  descent  of  10  to  15  feet  in  25  rods  east.  Through 
section  11  they  range  from  1,135  to  1,147  feet,  being  highest  in  the  southeast 
quarter  of  the  section,  where  the  descent  eastward  is  20  feet  or  more.  These 
beach  deposits  are  sand  and  gravel,  with  pebbles  up  to  IJ  or  2  inches  in 
diameter,  massed  in  flattened  hillocks  or  swells,  mostly  ridged  lengthwise 
with  the  shore  and  occasionally  inclosing  hollows  without  outlet.  The  for- 
mation has  a  width  of  a  quarter  of  a  mile  or  more  in  its  northward  course 
through  the  west  part  of  the  east  half  of  section  11.  An  undulating  sur- 
face of  till  rises  slowly  to  the  west,  while  on  the  east  a  verj^  smooth  expanse 
of  till  sinks  slowly  toward  the  Red  River. 

Herman  beacli  ridge,  30  rods  wide,  in  or  near  the  east  edge  of  the 
southeast  quarter  of  section  2,  township  146,  range  55,  1,125  feet.  Irreg- 
ular accumulations  of  the  higher  beach  a  quarter  of  a  mile  fartlier  west  rise 
approximately  to  1,140  feet.     These  upper  deposits  and  those  described  in 


HEEMAN  BEACH  AT  GOLDEN  LAKE.  329 

the  last  two  paragraphs  indicate  that  this  area,  which  was  covered  by  a 
southwardly  projecting  lobe  of  the  ice-sheet  at  the  time  of  the  accumula- 
tion of  the  eighth  or  Fergus  Falls  moraine,  experienced  an  earlier  nplift 
than  adjacent  tracts  of  the  lake  border,  giving  to  this  part  of  the  earliest 
and  highest  Herman  beach  an  altitude  15  or  20  feet  above  the  normal  and 
regular  plane  of  the  corresponding  beach  deposits  on  both  the  south  and  the 
north. 

Crest  of  the  Herman  beach,  a  definite  ridge  25  to  30  or  40  rods  wide, 
through  the  east  half  of  section  2,  township  146,  range  55,  1,122  to  1,135 
feet,  10  to  15  feet  above  the  land  east,  and  with  a  depression  of  6  to  8  feet 
on  the  west.  In  the  south  part  of  section  35,  township  147,  range  55,  the 
beach  ridge  is  merged  in  a  flat  eastwardly  sloping  area  of  sand  and  fine 
gi'avel  at  1,135  to  1,120  feet,  underlain  by  till  at  the  depth  of  a  few  feet. 
The  beach  ridge  reappears  in  the  north  part  of  this  section  35  at  1,125  to 
1,130  feet. ' 

Through  sections  26  and  23,  township  147,  range  55,  the  Herman  shore 
is  marked  by  swells  and  flattened  ridges  of  sand  and  fine  gravel  at  1,130  to 
1,143  feet,  occupying  a  width  of  an  eighth  to  a  third  of  a  mile,  with  a 
depression  of  several  feet  along  their  west  side.  Four  sloughs,  at  the  ele- 
vation of  about  1,120  feet,  lie  within  the  east  part  of  these  beach  deposits, 
or  on  their  east  border,  in  the  southeast  quarter  of  section  23.  In  the  south 
part  of  section  14  this  massive  but  iri-egular  beach  has  an  elevation  of 
1,132  feet  on  the  east  side  of  a  large  slough. 

In  the  middle  of  section  14,  township  147,  range  55,  the  beach  assumes 
a  definitely  ridged  form  and  extends  thus  northward  along  the  east  side  of 
Golden  Lake,  which  owes  its  existence  to  this  barrier.  Crest  of  the  beach, 
through  the  center  and  north  part  of  section  14,  1,132  to  1,137  feet;  in 
section  11,  east  of  Golden  Lake,  1,132  to  1,141  feet;  and  at  Golden  Lake 
post-office,  in  the  east  edge  of  the  southwest  quarter  of  section  2,  1,138 
feet.  An  eighth  of  a  mile  north  from  the  south  end  of  this  lake  the  action 
of  its  waves  has  eroded  the  greater  part  of  the  beach  ridge.  The  material 
of  the  beach  exposed  by  an  excavation  near  the  post-office  is  coarse  gravel, 
with  very  abundant  pebbles  up  to  3  inches  and  occasionally  4  to  6  inches 
in  diameter. 


330  THE  GLACIAL  LAKE  AGASSIZ. 

Golden  Lake  water,  July  28,  1885,  1,122  feet  above  the  sea;  highest 
level  reached  by  this  lake  in  recent  years,  1,128  feet.  It  is  a  beautiful 
sheet  of  water,  1^  miles  long  and  a  quarter  to  a  third  of  a  mile  wide.  Its 
west  shore  is  moderately  undulating  till,  with  the  highest  swells  20  to  30 
feet  above  the  lake.  In  a  few  places  its  grassed  bluffs  rise  steeply  from  the 
Avater's  edge  10  to  20  feet.  Farther  west  the  rolling  surface  of  till,  seen 
for  a  distance  of  3  or  4  miles,  rises  to  1,225  or  1,250  feet.  This  lake  has  no 
trees  on  its  margin,  excepting  two  small  cottonwoods,  each  about  25  feet 
high,  on  its  northwest  shore;  bushes  grow  in  several  places,  mostly  on  the 
east;  but  the  greater  part  of  the  lake  border,  like  all  the  surrounding 
country,  is  prairie. 

Beach  ridge  through  the  north  part  of  section  2,  township  147,  range 
55,  1,138  to  1,132  feet.  In  the  south  half  of  section  35,  township  148, 
range  55,  it  has  been  mostly  eroded  by  a  lake  which  borders  this  beach  on 
the  east  from  the  north  part  of  section  2  to  the  north  part  of  section  35, 
having  a  length  of  1  mile  and  a  width  of  an  eighth  to  a  fourth  of  a  mile. 
The  elevation  of  this  lake  is  1,104  feet  It  has  no  trees  or  bushes,  except- 
ing a  few  willows  4  to  6  feet  high,  near  the  middle  of  its  west  side,  and  is 
wholly  surrounded  by  hard,  grassy  shores.  Crest  of  the  beach  west  of 
the  north  part  of  this  lake,  1,140  to  1,142  feet,  and  through  the  south  half 
of  section  26,  1,137  to  1,142  feet,  similarly  bordered  on  the  east  by  two 
lakelets,  which  have  approximately  the  same  height  as  the  preceding,  1,104 
feet.  The  land  east  of  these  three  lakes  is  flat,  1,113  to  1,117  feet  near 
them,  with  a  very  gentle  slope  descending  thence  eastward. 

More  diff"use  and  irregular  beach  deposits  in  north-to-south  swells  and 
short,  massive  ridges  of  gravel  and  sand,  inclosing  occasional  hollows  with 
no  oixtlets,  some  of  which  hold  small  ponds  and  sloughs,  extend  from  the 
north  edge  of  section  26  northward  through  the  west  half  of  section  23, 
township  148,  range  55,  with  an  elevation  of  about  1,135  feet.  The 
depression  on  the  west  is  some  5  feet  lower,  and  on  the  east  there  is  a 
descent  of  10  feet  from  the  crest  to  the  base  of  the  beach.  Fingals  Creek, 
in  the  northwest  corner  of  section  23,  where  it  intersects  the  beach,  has  a 
height  of  about  1,110  feet.  Undulating  and  rolling  till  Avithin  3  or  4  miles 
westward  rises  to  1,250  feet. 


THE  UPPER  OE  HEEMAN  BEACHES.  331 

Herman  beach,  tln-ough  the  west  part  of  section  14,  township  148, 
range  55,  1,142  to  1,147  feet,  being  mainly  a  somewhat  typical  ridge,  with 
short  swells  of  beach  gravel  and  sand  on  its  east  side  10  to  15  feet  lower, 
inclosing  hollows,  but  few  or  no  sloughs.  Two  lakes  at  1,110  feet,  approxi- 
mately, lie  close  east  of  this  beach,  near  the  center  and  in  the  northwest 
quarter  of  this  section.  They  are  bordered  on  the  east  by  land  10  feet 
higher,  from  which  a  very  gentle  descent  sinks  toward  the  Red  Rivei\ 

Continuation  of  this  beach  ridge  northward  through  the  east  edge  of 
section  10,  township  148,  range  55,  1,142  to  1,146  feet,  3  to  5  feet  above 
the  depression  on  its  west  side.  On  the  east,  three  lakelets  at  1,120  feet, 
approximately,  lie  in  the  west  edge  of  the  northwest  quarter  of  section  11, 
each  being  about  20  rods  long  from  south  to  north  and  15  rods  wide.  Crest 
of  beach  ridge,  30  to  40  rods  wide,  extending  nearly  due  north  through 
the  east  edge  of  section  3,  1,144  to  1,150  feet;  east  base,  about  1,125  feet; 
depression  on  the  west,  5  to  10  feet,  nearly  level  upon  a  width  of  40  rods; 
beyond  is  an  ascent  of  undulating  and  rolling  till  to  1,250  feet  within  2  or 
3  miles.  In  the  southwest  quarter  of  section  36,  township  149,  range  55, 
Lind,  this  Herman  shore  is  marked  by  irregular  swells  and  massive  short 
ridges  of  gravel  and  sand,  with  occasional  inclosed  sloughs.  This  is  suc- 
ceeded by  a  half  mile  of  the  ordinary  continuous  single  ridge,  1,147  to 
1,150  feet. 

Magnificent  beach  ridge,  passing  north-northwest  through  the  east  part 
of  sections  26  and  23,  Lind,  1,147  to  1,150  feet.  A  road,  which  was  formerly 
an  Indian  trail,  runs  on  its  top  here  and  for  several  miles  northward.  This 
beach  is  composed  of  the  usual  sand  and  gravel,  thickly  filled  with  j^ebbles 
up  to  2  and  rarely  4  inches  in  diameter.  It  forms  a  broad,  wave-like  ridge 
30  to  40  rods  wide,  including  the  slopes.  On  its  west  side  is  a  depression  of 
5  to  10  feet,  20  to  60  rods  wide,  which  is  moist  grass  land,  excepting  a  small 
reedy  slough  in  the  south  edge  of  section  11.  On  the  east  side  of  this  upper 
Herman  beach  there  is  a  very  smooth  slope  descending  25  or  30  feet  in  as 
many  rods.  Next  is  a  nearly  level  belt  20  to  60  rods  wide,  increasing  in 
width  from  south  to  north,  succeeded  by  a  lower  Herman  beach  ridge  rising 
8  to  10  feet,  with  its  crest  at  1,127  to  1,130  feet,  or  20  feet  below  the  upper 
beach.     These  parallel  Herman  beaches  are  very  finely  developed  thus  for 


332  THE  GLACIAL  LAKE  AGASSIZ. 

nearly  6  miles,  passing  north  through  sections  23,  14,  11,  and  2,  Lind,  and 
the  southwest  part  of  section  35,  township  150,  range  55.  High  portion 
of  the  upper  beach  in  the  south  edge  of  section  14,  1,153  feet,  and  depres- 
sion west,  1,142  feet;  crest  onward  through  this  section,  1,153  to  1,149  feet. 
In  the  north  part  of  section  1 1  and  the  south  edge  of  section  2  it  is  a  few 
feet  lower,  is  irregular  in  height  and  outlines  because  of  intersecting  watei-- 
courses,  and  has  a  less  continuous  and  shallower  depression  on  its  west  side. 
In  section  2,  however,  both  beach  ridges  are  finely  displayed,  having  the 
same  contour  as  sovithward.  Crest  of  upper  beach  in  sections  2  and  35, 
1,152  to  1,155  feet;  depression  on  the  west,  8  to  15  feet,  partly  occupied 
by  a  long  slough.  The  northwest  part  of  section  35,  in  the  course  of  these 
beaches,  is  lower  smooth  till,  with  no  deposits  of  sand  and  gravel. 

Goose  River,  near  the  north  line  of  the  northwest  quarter  of  section 
35,  and  the  Little  Groose  River,  in  the  north  part  of  section  15,  township 
150,  range  55,  where  they  cross  the  ancient  lake  shore,  are  in  valleys  about 
30  feet  deep,  eroded  in  till.  Each  consists  of  pools  5  to  7  feet  deep  and  10 
to  20  feet  wide,  alternating  with  other  portions  so  narrow  that  one  may  step 
across  them. 

In  the  east  part  of  the  west  half  of  section  26  and  the  southwest  corner 
of  section  23,  township  150,  range  55,  the  upper  Hennan  shore  is  offset  a 
third  of  a  mile  east  from  the  remainder  of  its  course  and  consists  of  massive, 
irreo-ular  swells  of  till,  partly  overspread  with  gravel  and  sand,  1,152  to 
1,160  feet.  Among  them  are  hollows  4  to  6  feet  deep,  without  outlet,  and 
their  entire  belt,  a  quai'ter  of  a  mile  wide,  is  crossed  by  depressions  as  low 
as  1,145  feet.  Through  section  22  this  shore  bears  a  typical  beach  ridge  of 
sand  and  gravel,  40  to  50  rods  wide,  1,157  feet,  with  depression  of  10  to  15 
feet  on  the  west;  descent  of  the  eastern  slope,  20  to  25  feet  in  30  or  40  rods. 
In  section  15  this  upper  beach,  1,152  to  1,157  feet,  has  a  quite  irregular 
form,  chiefly  due  to  erosion  by  the  Little  Goose  River  and  its  small  tribu- 
taries. It  is  again  exhibited  in  its  ordinary  type  through  section  10,  being 
a  ridge  25  or  30  rods  wide,  with  crest  at  1,155  to  1,157  feet,  15  to  20  feet 
above  its  east  base  and  with  a  narrow  depression  of  4  to  8  feet  on  the  west; 
throuo-h  the  west  part  of  section  3,  township  150,  range  55,  and  the  west  edge 
of  the  southwest  quarter  of  section  34,  township  151,  range  55,  1,157  to 


THE  ELK  VALLEY  DELTA.  333 

1,159  feet,  excepting  gaps  cut  by  small  watercourses;  and  in  the  east  edge 
of  the  northeast  quarter  of  section  33,  1,154  to  1,157  feet.  Thirty  rods 
west  from  the  northeast  corner  of  this  section  33  its  elevation  is  1,155  feet, 
with  slopes  descending  12  feet  eastward  and  8  feet  westward. 

Lower  Herman  beach,  a  half  mile  to  tlu-ee-fourths  of  a  mile  east  of 
the  foregoing,  in  the  west  edge  of  sections  14  and  11  and  the  east  edge 
of  section  3,  township  150,  range  55,  1,130  to  1,135  feet,  from  which  there 
is  a  descent  of  5  feet  to  its  west  base  and  10  feet  to  the  east.  From  the 
southeast  quarter  of  section  34,  township  151,  range  55,  this  beach  passes 
northeasterly  to  Larimore. 

Upper  Herman  beach,  a  well-defined  ridge,  running  north  through  the 
east  part  of  section  28,  township  151,  range  55,  1,155  to  1,159  feet;  thence 
north-northwesterly  thi'ough  sections  21  and  16,  1,157  to  1,160  feet,  and 
through  the  southwest  part  of  section  9,  the  northeast  part  of  section  8,  and 
the  southeast  quarter  of  section  5, 1,157  to  1,162  feet.  Wlaere  it  is  crossed  by 
the  Devils  Lake  line  of  the  Great  Northern  Railway,  in  the  south  part  of  the 
northeast  quarter  of  section  5,  about  4 J  miles  west  of  Larimore,  its  crest 
was  at  1,162  feet,  4  feet  above  the  track,  and  it  holds  the  same  height  for 
about  50  rods  northeastward.  Two-fifths  of  a  mile  east  from  this  beach 
the  railroad  crosses  a  second  beach  deposit  whose  crest  and  the  track  are  the 
same,  1,146  feet. 

DELTA    OF    THE    ELK    VALLEY. 

(PLATE    XXIX.) 

Nearly  level  land  reaches  4  miles  westward  from  Larimore  along  the 
Devils  Lake  railway  line,  averaging  1,130  feet  above  the  sea,  and  varying 
only  2  or  3  feet  above  and  below  this  level.  Beneath  the  rich  black  soil 
here  and  elsewhere,  all  about  Larimore,  are  stratified  sand  and  fine  silt  free 
from  gravel.  The  beach  ridges  near  this  town  are  consequently  composed 
wholly  of  sand,  quite  in  contrast  with  their  usually  coarser  material. 

The  underlying  beds  consist  largely  of  sand  from  the  Fort  Pierre 
shale,  and  were  derived  probably  in  part  from  erosion  by  the  head  streams 
of  the  Turtle  and  Goose  rivers  in  this  Cretaceous  formation,  which  here 
constitutes    the    highland  west  of   Lake  Agassiz,  thinly  covered  by  till. 


334 


THE  GLACIAL  LAKE  AGASSIZ. 


Considerable  channeliug  of  the  valleys  iu  wliicli  these  streams  flow  appears 
thus  to  have  been  accomplished  before  the  laud  was  uplifted  and  the  lake 
receded  to  i  ts  Norcross  and  lower  shores.  This  delta  accmnulation,  consist- 
ing partly  of  alluvium  from  stream  erosion  after  the  departure  of  the  ice, 
but  evidently  in  far  larger  measure  of  modified  drift  supplied  by  streams 
from  the  melting  ice  in  which  it  had  been  held,  occupies  a  width  of  6  to  12 
miles,  and  stretches  about  35  miles  southward  from  McCanna,  by  Larimore, 
Northwood,  and  Hatton,  to  the  vicinity  of  Portland.  Its  thickness  at 
Larimore,  as  .shown  in  fig.  14,  is  60  feet,  and  doubtless  its  average  thick- 
ness is  as  much  as  30  or  40  feet  upon  its  area  of  about  300  square  miles. 
It  was  deposited  in  the  edge  of  Lake  Agassiz  during  the  first  and  second 
Herman  stages,  for  these  shores    marked  by  beach  ridges,  are  above  the 


90i^ 


//<70-s-:^-.-j':i; 


Fig.  14. — Section  across  tht-  delta  of  the  Elk  Valley.    Horizontal  scale,  3  miles  to  an  inch. 


delta;  but  the  third  and  fourth  Herman  beaches  extend  across  it,  passing 
close  east  of  Larimore.  The  Norcross  and  Tintah  shore-lines  lie  near  its 
eastern  boundary,  for  the  greater  part  upon  its  edge,  but  it  has  not  been 
conspicuously  eroded.  Farther  east  the  surface  is  mainly  till  for  the  next 
15  miles  or  more,  descending  toward  the  Red  River,  which  is  bordered  on 
this  latitude  iu  North  Dakota  by  a  belt  of  alluvial  clay  and  silt  only  a  few 
miles  wide. 

A  section  of  the  beds  forming  this  delta  is  furnished  by  the  well  at  the 
Sherman  House,  Larimore,  which  was  dug  20  feet  and  bored  40  feet,  as 
follows:  Soil,  2  feet;  fine  sandy  and  clayey  silt,  without  coarse  sand, 
gravel,  or  stones,  5  feet;  fine  yellowish  sand,  with  less  clay,  being  mainly 
siliceous,   13  feet;  and  dark  sand,  very  soft  to  bore  through,  two-thirds 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.   XXIX. 


us  euN  tt  CO  r 


MAP  OF  THE  WESTORN  SHORES  OF  J^KE  AGASSIZJNCEUDING  THE  FXK  VALLEY  DELTA, 
IN  GRAND  FORIvS  COUNTY  AND  PARTS  OF  ^\DJ0IN1M;  COl^nES,NOH'ni   DAKOTA. 


I^aJkre  Area 


Sciile,  6  miles  to  aji  inch. 

]  DolLa  i  I 


Moraines 


AJlitHflPS      of     v(tn \\'(i\'     stfitioTis      itrc     noird      in     f'cpl     nhovc     tfip     sen  ■ 


THE  ELK  VALLEY  DELTA.  335 

Cretaceous  shale  in  particles  up  to  a  twentieth  of  an  inch  in  diameter,  40 
feet,  with  much  water.  Hard  blue  till  was  found  at  the  bottom.  The  other 
wells  of  this  town  are  said  to  obtain  their  supply  of  water  at  a  depth  of 
about  20  feet,  in  the  upper  part  of  this  sand  derived  chiefly  from  shale.  In 
Northwood  and  Hatton,  also,  water  is  found  at  depths  of  only  10  to  20  feet 
before  reaching  the  base  of  the  delta  sand. 

The  volume  of  this  extensive  sand  and  silt  delta  is  about  1^-  or  2  cubic 
miles.  It  occupies  more  than  thrice  the  area  of  the  delta  of  the  Pembina 
River,  but  is  much  shallower,  so  that  they  are  nearly  equal  in  their  cubic 
contents,  or  this  is  the  smaller;  and  it  has  nine  times  or  perhaps  twelve 
times  the  volume  of  either  of  the  two  deltas  of  this  lake  in  Minnesota, 
lying  on  the  Buff"alo  and  Sand  Hill  rivers.  Yet  here  no  stream  of  signifi- 
cant size  enters  the  lake  area.  There  are,  indeed,  not  less  than  a  dozen 
small  streams,  the  headwaters  of  the  Turtle  and  Goose  rivers,  which 
descend  to  the  delta  from  the  till-covered  Cretaceous  highland  on  the  west; 
but  none  of  them  has  a  large  valley  or  extensive  basin  of  ch-ainage,  and  it 
would  be  difficult  to  decide  which  one  of  three  or  four  is  most  worthy 
of  consideration.  The  delta,  however,  in  its  position,  the  outlines  of  its 
extent,  and  the  directions  and  rate  of  its  slopes,  seems  independent  of 
them  all. 

Northward  from  Larimore  and  McCamia,  where  the  surface  of  this 
delta  is  highest,  a  very  noteworthy  topographic  feature  of  the  western 
border  of  the  lacustrine  area  has  received  the  name  of  Elk  Valley  in  its 
southern  portion,  and  in  its  northern  continuation  is  called  the  Golden 
Valley.  These  are  parts  of  one  continuous  belt  which  was  at  first  the 
course  of  a  glacial  river,  and  afterward  became  a  sound  or  strait  extending 
about  40  miles  along  the  coast  of  Lake  Agassiz  at  its  highest  stage.  It 
was  divided  from  the  main  lake  by  a  series  of  several  small  islands  of 
knoUy  and  hilly  till,  occasionally  connected  together  by  a  low  beach 
embankment  or  bar,  formed  by  the  lake  waves.  The  Elk  Valley  is  com- 
monly regarded  as  beginning  at  Larimore,  but  it  may  more  strictly  be  said 
to  begin  9  miles  farther  north,  at  the  most  southern  of  its  inclosing  islands. 
It  extends  north  from  Larimore  29  miles  to  Ramsey s  Groves,  on  the  North 
Branch  of  the  Forest  River,  with  a  width  of  about  4  miles  for  the  greater 


336  THE  GLACIAL  LAKE  AGASSIZ. 

part  of  its  extent,  diminishing  at  the  north  to  2  miles.  The  narrower  pro- 
longation of  this  tract,  known  as  the  Golden  Valley,  varies  from  2  miles  to 
only  1  mile  in  width  along  its  course  of  18  miles  to  the  North  Branch  of 
Park  River,  1  to  2  miles  west  of  Gardar.  Originally  the  whole  length 
of  this  belt  was  called  the  Elk  Valley,  which  seems  to  be  a  translation  of 
its  aboriginal  name;  but  the  name  Golden  Valley,  proposed  for  its  north- 
ern portion  by  the  Ramsey  brothers,  living  at  Ramseys  Groves,  in  Vernon 
Township,  has  come  into  universal  use  for  the  narrow  part  of  the  valley 
extending  thence  northward. 

The  Golden  and  Elk  valleys  have  no  river  now  running  along  their 
continuous  depression.  Instead  it  is  crossed  by  numerous  streams  which 
form  the  Turtle,  Park,  and  Forest  rivers,  descending  from  the  highland 
west  of  Lake  Agassiz  and  finding  their  way  between  or  through  the 
morainic  islands  east  of  the  valley.  But  during  the  stage  in  the  departure 
of  the  ice-sheet  when  these  islands  were  being  accumulated  on  the  western 
margin  of  its  Minnesota  lobe,  contemporaneous  with  the  formation  of  the 
Leaf  Hills  and  with  the  completion  of  the  prominent  compound  moraine 
south  of  Devils  Lake,  a  great  river  flowing  from  the  melting  ice-fields  and 
laden  with  their  drift  ran  with  a  strong  current  in  this  long,  nearly  straight 
valley,  bringing  to  its  debouchure  into  Lake  Agassiz  at  McCanna  the  sand 
and  silt  of  this  delta.  A  portion  of  its  freight  was  even  borne  35  miles 
onward  in  the  shallow  water  of  the  lake,  forming  the  southern  part  of  the 
delta,  which  was  probably  held  to  the  western  side  of  the  lake  area  by 
the  barrier  of  this  ice-lobe.  That  the  sand  and  silt  were  thus  supplied 
chiefly  from  the  englacial  di-ift,  and  only  in  small  part  from  erosion  by  the 
streams  that  now  exist,  is  proved  by  the  position  of  the  axial  thickest  and 
highest  portion  of  the  delta,  separated  from  the  western  shore  of  Lake  Agas- 
siz by  a  broad,  shallow  depression  hi  which  the  numerous  sources  of  the 
Goose  River  are  diverted  from  their  eastward  course  and  carried  to  the  south 
in  a  united  stream.  Whatever  alluvium  these  tributaries  have  added  to  the 
delta,  both  while  the  lake  was  here  and  since  it  was  withdrawn,  has  been 
insufiicient  to  raise  their  channels  the  small  amount  that  would  give  them 
passage  across  the  delta  in  their  normal  com'se  toward  the  east. 


THE  ELK  AND  GOLDEN  VALLEYS.  337 

SHORE    WEST    OF    THE    ELK    AND    GOLDEN    VALLEYS. 

(PLATES   XXIX   AND  XXX.) 

Througli  section  32,  Elm  Grove,  the  upper  beach  runs  northwesterly, 
its  elevation  being  1,160  to  1,163  feet  above  the  sea.  Its  material  is  coarse 
gravel,  with  pebbles  up  to  6  inches  in  diameter,  in  part  accumulated,  as  a 
ridge  10  or  15  feet  above  the  land  at  its  base  northeast  and  5  to  8  feet 
above  its  southwest  base,  and  in  part  lying  on  the  flank  of  swells  of  very 
stony  till,  the  crests  of  which  are  only  5  to  10  feet  higher  than  the  beach. 
This  till  or  morainic  drift  contains  a  multitude  of  granitic  and  limestone 
bowlders  up  to  li  feet  in  diameter,  bvit  few  or  none  of  larger  size.  In  the 
rolling  till  which  rises  thence  westward  to  1,250  or  1,300  feet  within  2 
or  3  miles  are  many  granitic  bowlders  up  to  5  feet  or  more  in  diameter, 
exceeding  the  usual  proportion  in  the  till  of  this  region. 

In  the  north  edge  of  section  32  and  the  south  part  of  section  29,  Elm 
Grove,  this  beach  is  the  terrace-like  border  of  a  nearly  level  tract  of  sand 
and  gravel  an  eighth  of  a  mile  or  more  in  width,  at  an  elevation  of  1,171  to 
1,173  feet.  The  bordering  slope  is  beach  gravel,  with  its  base  at  1,155 
to  1,158  feet;  but  the  slow  descent  thence  eastward  is  till,  somewhat 
eroded  by  wave  action  and  having  many  small  and  large  granitic  bowlders 
up  to  4  or  6  feet  in  diameter  strewn  on  the  surface  or  partially  covered 
by  the  soil.  In  the  northeast  quarter  of  section  30  this  upper  Herman 
beach  is  typically  developed,  being  a  gracefully  rounded  ridge  of  sand  and 
gravel,  25  or  30  rods  wide;  crest,  1,165  to  1,166  feet;  foot  of  eastern  slope, 
1,150  feet;  depression  west,  usually  2  to  5  feet,  beyond  which  is  a  slowly 
ascending  area  of  smooth,  undulating  till. 

Upper  beach  through  section  19,  Elm  Grove,  a  low,  rounded  ridge  of 
sand  and  gravel  about  25  rods  wide;  crest,  1,166  to  1,168  feet;  base  of  its 
east  slope  on  the  north  line  of  this  section,  1,158  feet.  In  the  southwest 
quarter  of  section  1 8  this  beach  is  cut  by  the  South  Branch  of  the  Turtle 
River;  its  elevation  in  this  section  south  of  the  stream  is  1,167  to  1,168 
feet.  There  is  no  considerable  valley  here,  and  the  creek  runs  only  in 
spring  or  after  uuusiial  rains,  being  reduced  to  stagnant  pools  during  the 
rest  of  the  year.  Within  2  miles  southeast,  however,  it  becomes  a  living 
MON  XXV — '■ — 22 


338  THE  GLACIAL  LAKE  AGASSIZ. 

stream,  fed  by  very  cold  spi'ings,  and  tlieuce  to  the  secondary  Herman 
beach  near  Larimore  it  has  cut  a  valley  50  to  90  feet  deep. 

Elm  Grove,  comprising-  about  5  acres,  is  on  this  creek,  a  third  of  a  mile 
east  of  the  upper  Herman  shore-line,  which  continues  north-northwestward 
tlu-ough  the  southwest  part  of  section  18,  Elm  Grove  ToAvnship,  and  the 
northeast  edge  of  section  13,  Niagara,  to  the  west  side  of  Little  Elm 
Grove,  10  acres  or  more  in  extent,  in  the  east  part  of  section  12,  Along 
this  distance  of  1^  miles  the  surface  presents  a  very  favorable  slope,  from 
1,150  to  1,200  feet  elevation,  on  which  a  beach  ridge  or  definite  beach 
deposits  would  usually  be  found  well  developed ;  but  the  waves  and  cur- 
rents of  Lake  Agassiz  could  not  act  efficiently  here,  because  this  area  lay 
in  the  lee  of  islands  and  of  a  wave-formed  bar  or  beach  several  miles  to 
the  east,  which  are  the  eastern  boundary  of  the  Elk  Valley.  Consequently 
deposits  of  beach  sand  and  gravel  are  scanty  on  the  upper  western  shore 
of  Lake  Agassiz  here  and  for  40  miles  northward  along  the  extent  of  the 
Elk  and  Golden  valleys,  east  of  which  a  narrow  chain  of  islands  and  bars 
rose  above  the  surface  of  Lake  Agassiz  during  its  highest  Herman  stage. 
Between  the  South  Branch  of  Turtle  River  and  Little  Ehn  Grove  the 
beach  formation  consists  only  of  a  thin  covering  of  sand  and  gravel  spread 
on  the  sloping  area  of  till,  at  an  elevation  from  1,160  to  1,175  feet.  Sev- 
eral of  the  small  grassy  channels  eroded  here,  dry  excepting  in  spring  and 
times  of  excessive  rain,  are  almost  completely  paved  with  stones  up  to  1  or 
2  feet  in  diameter,  but  few  stones  occur  upon  the  adjoining  surface  of  till. 

From  the  Little  Elm  Grove  the  highest  western  shore  of  Lake  Agassiz 
(consisting  of  a  similar  slope  of  till  ascending  gently  westward,  with  incon- 
spicuous deposits  of  beach  gravel  and  sand,  not  accumulated  in  any  distinct 
ridge,  but  probably  recognizable  almost  continuously)  extends  northward 
through  sections  12  and  1,  Niagara,  and  sections  31  and  30,  Agnes,  to  the 
central  part  of  Bachelors  Grove,  which  it  passes  through  in  the  west  half 
of  section  30.  This  grove  borders  the  head  stream  of  Turtle  River  for  1^ 
miles,  with  an  average  width  of  about  a  quarter  of  a  mile,  thus  comprising 
approximately  250  acres.  It  is  dense  woods,  chiefly  elm  and  basswood  in 
its  east  half,  but  nearly  all  bur  oak  for  the  west  half  Much  bm-  oak  is 
also  found  along  several  miles  of  this  stream  next  westward,  but  it  is  not 


HEEMAN  SHORE  WEST  OF  THE  ELK  VALLEY.        339 

seen  from  the  margin  of  Lake  Agassiz,  being  hidden  in  the  valley,  40  to 
50  feet  deep,  which  the  stream  has  eroded  in  that  area  of  undulating  and 
rolling  till. 

Herman  beach,  for  the  first  mile  or  more  north  from  Bachelors  Grove, 
passing  through  the  northwest  quarter  of  section  30  and  the  west  edge  of 
section  19,  Agnes,  1,165  to  1,170  feet.  This  is  mostly  a  well-defined  beach 
ridge,  20  to  30  rods  wide,  composed  of  sand  and  gravel,  with  pebbles  up 
to  2  inches  in  diameter.  It  rises  slowly  to  a  height  of  10  or  12  feet  above 
the  flat  land  on  the  east  and  is  bordered  on  the  west  by  a  depression  of  1 
to  3  feet,  beyond  which  a  smoothly  undulating  and  rolling  surface  of  till 
rises  to  an  elevation  of  1,200  and  1,250  feet  at  a  distance  of  3  miles.  In 
the  northwest  quarter  of  this  section  19  the  beach  deposit  becomes  complex, 
consisting  of  several  irregular  ridges  rising  5  to  8  feet  above  their  bases, 
1,167  to  1,170  feet  above  sea-level,  with  inclosed  hollows,  and  the  depres- 
sion close  west  occasionally  sinks  to  1,155  feet. 

Through  sections  13  and  12,  the  southwest  part  of  section  1,  and  in 
section  2,  Oakwood,  to  the  grove  on  the  north  line  of  section  2  at  the 
junction  of  the  north  and  south  branches  of  Lost  Creek,  and  thence  north- 
east and  north  through  section  35,  Elkmount,  the  Herman  shore,  between 
1,160  and  1,170  feet,  is  not  marked  by  any  considerable  deposits  of  gravel 
and  sand.  Farther  north  this  shore  is  distinguished  not  only  by  a  notice- 
able change  in  the  topographic  features  along  a  nearly  level  line  at  1,170 
feet,  dividing  the  very  flat  area  of  the  glacial  lake  from  the  undulating  and 
rolling  till  on  the  west,  but  also  by  occasional  beach  deposits.  Through 
the  south  half  of  section  26,  Elkmount,  a  somewhat  typical  beach  ridge  of 
sand  and  gravel,  15  to  25  rods  wide,  with  a  depression  of  3  to  6  feet  on  its 
west  side,  runs  north  and  northwest,  its  crest  being  at  1,175  to  1,170  feet, 
declining  from  south  to  north.  On  the  east  its  slope  falls  5  to  10  feet  in  10 
to  20  rods;  and  thence  a  more  gentle  descent,  with  surface  of  sand  and  fine 
gravel,  sinks  to  1,155  feet  within  an  eighth  of  a  mile.  In  the  northwest 
quarter  of  this  section  26  the  beach  ridge  ceases  and  is  succeeded  north- 
ward by  an  expanse  of  nearly  flat  till,  which  along  the  north  line  of  this 
section  sinks  eastward  from  1,175  to  1,155  feet. 


340  THE  GLACIAL  LAKE  AGASSIZ. 

Elk  Valley,  for  1 2  miles  from  Elm  Grove  and  McCanna  north  to  the 
Forest  River,  is  nearly  constant  in  elevation,  which  is  1,155  feet  on  its 
west  border  and  1,1  o5  feet  near  its  east  side,  its  average  width  being  about 
4  miles. 

Upper  Herman  beach,  a  definite  and  massive  ridge  of  sand  and  fine 
gravel,  25  to  40  rods  wide,  for  a  half  mile  south  from  the  South  Branch  of 
Forest  River,  in  the  west  part  of  the  northwest  quarter  of  section  14,  Elk- 
mount,  1,173  to  1,178  feet,  passing  north  and  northwest,  with  a  descent  of 
12  to  15  feet  on  the  east  and  a  depression  of  4  to  8  feet  on  the  west. 

Beyond  this  branch  of  the  Forest  River,  in  the  north  half  of  section 
lO,  Elkmount,  the  beach  ridge,  similar  in  outluie,  with  its  crest  at  1,174  to 
1,179  feet,  is  the  site  of  an  abandoned  railway  grade,  on  accotmt  of  which 
its  material  is  well  exhibited.  It  is  sand  and  gravel,  and  three-fourths  of 
the  pebbles,  mostly  less  than  2  inches  in  diameter,  are  dark-gray  slaty 
shale.  Twenty  miles  to  the  south-southeast  the  same  shale  in  small  grains 
makes  fully  two-thirds  of  a  stratum  of  sand  that  extends  from  20  to  60  feet 
in  depth  in  the  well  at  the  Sherman  House,  Larimore.  Pebbles  of  it  were 
also  observed  in  kame-like  deposits  of  gravel  and  sand  near  Balaton,  Lyon 
County,  in  southwestern  Minnesota.  During  the  further  exploration  of  the 
western  shore  of  Lake  Agassiz  this  shale  was  discovered  in  place,  and  is 
found  to  be  the  bed-rock,  of  Cretaceous  age,  which  forms  the  conspicuous 
escarpment  of  the  Pembina  Mountain,  though  even  there  it  is  generally 
covered  and  concealed  by  drift. 

Natural  surface  at  the  northwest  corner  of  section  3,  Elkmount,  on  the 
line  between  Grand  Forks  and  Walsh  counties,  1,181  feet.  The  upper 
Herman  shoi-e  passes  north-northwesterly  through  this  corner  of  section  3 
and  the  east  part  of  section  33,  Medford,  to  the  Middle  Branch  of  Forest 
River  (farther  east  formerly  called  Salt  River),  which  it  reaches  near  the 
center  of  the  east  half  of  section  28.  It  has  only  scanty  deposits  of  beach 
gravel  and  sand,  nowhere  forming  a  ridge;  instead,  the  surface  is  mainly 
till,  very  flat  east  of  this  shore,  but  undulating  or  rolling  westward. 

The  South  and  Middle  branches  of  Forest  River  occupy  valleys  25  to 
40  feet  deep  and  20  to  30  rods  wide.  They  are  bordered  with  groves,  or  at 
least  a  continuous  line  of  trees,  along  the  greater  part  of  their  course. 


SEMICIRCULAR  MARGINAL  MORAINES.  341 

111  the  northwest  quarter  of  section  28  and  the  west  part  of  section  21, 
Medforcl,  the  highest  shore-Hne  of  Lake  Agassiz  is  very  distinctly  marked, 
at  1,183  to  1,185  feet,  by  being  the  upper  edge  of  a  flat  slope  of  till,  proba- 
bly with  scanty  deposits  of  gravel  and  sand,  which  sinks  20  to  30  feet  in 
the  next  half  mile  eastward.  Farther  east,  for  the  width  of  3  or  4  miles 
across  the  Elk  Valley,  the  surface  elevation  is  1,160  to  1,125  feet. 

Just  west  of  this  shore-line  a  knolly  belt  of  morainic  drift,  bearing  a 
marvelous  profusion  of  bowlders,  occupies  a  width  of  25  to  50  rods,  gener- 
ally forming  a  single  series  of  hillocks  rising  15  to  30  or  35  feet.  These 
are  strewn  with  bowlders  of  all  sizes  up  to  5  feet  and  rarely  8  feet  in 
diameter,  so  plentiful  that  they  cover  a  third  or  even  half  of  the  surface. 
A  few  masses  of  limestone  were  observed,  but  fully  99  per  cent  of  the 
bowlders  are  Ai-chean  granite  and  gneiss.  This  is  the  most  eastern  portion 
of  a  semicircular  moraine  which  appears  to  have  been  accumulated  on  the 
eastern  boundary  of  a  lobe  of  the  ice-sheet  during  a  pause  in  its  retreat. 
From  sections  21  and  28,  Medford,  this  moraine  continues,  with  nearly  the 
same  features,  south  and  southwest  to  the  southeast  quarter  of  section  32, 
and  thence  west-southwest  by  Pilot  Knob,  in  the  northwest  quarter  of 
section  5,  Elkmount,  to  the  west  side  of  section  1,  township  154,  range  57, 
and  perhaps  beyond.  Its  hills  and  knobs  rise  25  to  75  feet  above  the  gen- 
eral level  of  the  adjoining  smoothly  undulating  till,  their  tops  being  1,250 
to  1,300  feet  above  the  sea.  To  the  north,  northwest,  and  west  it  reaches, 
with  similar  development,  in  a  great  curve  convex  to  the  northeast,  along 
an  extent  of  5  or  6  miles,  to  a  cluster  of  prominent  morainic  hills  rising  50 
to  75  feet,  situated  in  sections  2  and  3,  Cleveland.  This  moraine  matter 
was  doubtless  englacial;  among  its  multitude  of  both  large  and  small  rock 
fragments  a  half  hour's  search  failed  to  discover  any  marked  with  striae  or 
having  faces  planed  by  glaciation.  On  the  west  the  area  inclosed  by  this 
curving  moraine  is  very  smooth,  only  slightly  undulating  till,  at  1,185  to 
1,250  feet,  ascending  slowly  westward. 

Another  distinct  morainic  series,  similar  in  its  very  knolly  contour,  in 
its  material  (excepting  a  larger  proportion  of  gravel,  half  of  which  is  the 
Cretaceous  shale  before  described),  and  in  the  great  abundance  of  bowl- 
ders, nearly  all  granitic,  branches  from  the  preceding  in  the  north  part  of 


342  THE  GLACIAL  LAKE  AGASSIZ. 

section  8,  Medford,  and  sweeps  northeast  and  north  through  the  west  half 
of  section  4,  and  thence  northwest  and  west  through  sections  32,  29,  and 
19,  Vernon,  and  sections  13  to  16,  Norton,  to  a  group  of  morainic  hills 
about  75  feet  high,  a  mile  northwest  of  Gait  post-office.  Between  this 
curved  moraine  and  the  nearly  parallel  northern  part  of  the  preceding,  4 
miles  distant  to  the  south,  the  surface  is  very  smooth,  undulating  till,  rising 
slowly  toward  the  west. 

These  moraines,  with  their  east  base  at  1,185  to  1,170  feet  above  the 
sea,  formed  the  west  shore  of  Lake  Agassiz  at  its  highest  stage  for  nearly 
7  miles  between  the  Middle  and  North  branches  of  the  Forest  River.  The 
North  Branch  intersects  this  shore-line  near  the  center  of  section  20,  Ver- 
non, close  to  the  southwest  end  of  Ramseys  Grroves,  which  extend  thence 
about  a  mile  along  this  watercourse  in  the  north  pai't  of  section  20  and  the 
southeast  quarter  of  section  1 7.  The  stream  in  these  sections  has  no  valley, 
only  a  channel  20  to  30  feet  wide  and  10  feet  deep. 

Grolden  Valley,  on  the  north  line  of  sections  4  and  5,  Vernon,  has  an 
elevation  of  1,185  to  1,195  feet,  showing  an  ascent  of  10  feet  from  east  to 
west  in  its  width  of  2  miles.  About  the  same  transverse  slope,  raising 
tliewest  side  of  this  valley  10  or  15  feet  above  its  east  side,  is  found  along 
its  whole  extent  of  1 8  miles,  from  the  North  Branch  of  Forest  River  to  the 
Middle  and  North  branches  of  Park  River.  In  the  north  half  of  Vernon, 
and  thence  northward,  the  width  of  this  valley  varies  from  1|  miles  to  only 
1  mile.  It  is  flat,  and  consists  mainly  of  clay,  free  from  gravel;  but  wells 
find  gravel  intermixed  with  the  clay,  probably  till,  at  a  depth  of  a  few  feet, 
and  about  20  feet  from  the  surface  they  sometimes  encounter  a  water- 
bearing stratum  of  gravel,  chiefly  made  up  of  Cretaceous  shale. 

Natural  surface  at  the  southwest  corner  of  section  27,  Golden,  1,191 
feet.  Highest  part  of  Golden  Valley  south  of  the  South  Branch  of  Park 
River,  along  the  north  line  of  sections  27,  28,  and  29,  in  this  township,  1,199 
feet  on  the  east  to  1,211  feet  on  the  west.  Surface  at  schoolhouse  on  the 
west  side  of  the  northwest  quarter  of  section  21,  1,207  feet. 

South  Branch  of  Park  River  at  the  bridge  near  the  middle  of  the 
north  line  of  section  21,  Golden,  1,170  feet,  approximately;  bottom  land 
about  a  quarter  of  a  mile  wide,  10  to  15  feet  above  the  stream;  crest  of 


THE  GOLDEN  VALLEY.  343 

the  south  bluff  rismg  to  the  flat  belt  of  the  Golden  Valley,  1,191  to  1,209 
feet,  ascendmg  westward;  of  the  north  bluff,  1,189  to  1,205  feet. 

Golden  Valley,  on  the  north  line  of  section  5,  Golden,  1,195  to  1,205 
feet;  2  miles  farther  north,  on  the  north  line  of  section  29,  Lampton,  1,198 
to  1,208  feet.  In  this  northern  part  of  the  valley  limited  ti-acts  of  its  flat 
area  are  strewn  with  abundant  bowlders  up  to  2  feet,  and  less  frequently  3 
or  4  feet,  in  diameter.  They  are  probably  where  swells  of  till  rose  nearly 
to  the  surface  of  the  water  in  this  strait  of  Lake  Agassiz,  so  that  its  fine 
portions  were  swept  away  by  waves  and  currents,  to  be  deposited  elsewhere 
in  the  valley  as  clayey  silt,  leaving  the  masses  of  rock  which  could  not  be 
thus  removed.  Approaching  the  Middle  Branch  of  Park  River,  the  surface 
of  the  Golden  Valley  continues  very  smooth  and  flat,  but  it  ceases  to  have 
a  continuous  ascent  from  east  to  west,  some  portions  along  the  center  being 
depressed  a  few  feet.  Such  a  shallow  hollow  holds  a  slough  about  a  mile 
long  from  south  to  north  and  a  half  mile  wide  in  its  broadest  part,  at  1,193 
feet,  extending  from  the  north  edge  of  section  20  through  the  west  part  of 
section  17,  Lampton,  in  which  a  small  area  of  water  rem-ains  throughout 
the  year.  On  each  side  of  this  slough,  and  for  miles  south  and  north,  this 
valley  is  a  great  hay  meadow. 

The  west  border  of  the  Golden  Valley  was  the  most  western  shore  of 
Lake  Agassiz  in  its  highest  stage,  but  it  is  only  very  scantily  marked  by 
deposits  of  beach  gravel  and  sand,  because  of  its  sheltered  position  on  the 
western  and  leeward  side  of  this  naiTow  strait.  From  the  middle  of  section 
20,  Vernon,  this  shore-line  extends  in  a  quite  direct  course  a  few  degrees 
west  of  north  11  miles  tlu'ough  the  west  part  of  sections  17,  8,  and  5,  in 
this  township,  sections  32,  29,  20,  17,  8,  and  5,  Golden,  and  the  east  edge 
of  sections  31  and  30,  Lampton.  For  the  next  3  miles,  in  the  east  edge  of 
sections  19,  18,  and  7,  Lampton,  it  runs  nearly  due  north.  Thence  it 
turns  to  a  northwesterly  course  through  section  6  of  this  township,  and 
through  section  31,  Gardar.     In  this  vicinity  the  Golden  Valley  terminates. 

Bushes  and  trees  clothe  the  slo2:)e  on  the  west  side  of  the  Golden 
Valley  along  its  northern  part,  extending  to  the  south  line  of  Lampton; 
but  this  ascent  farther  south,  also  the  entire  extent  of  the  Golden  Valley, 


344  THE  GLACIAL  LAKE  AGASSIZ. 

the  drift  hills  forming  its  east  border,  and  the  vast  plain  of  the  Red  River 
Valley,  are  prairie,  excepting  that  narrow  belts  of  timber  border  the  water- 
courses. 

Smoothly  undulating  till  rises  slowly  from  the  west  side  of  the  southern 
part  of  the  Golden  Valley;  but  in  section  30,  Lampton,  rounded  hills  of  till 
attain  a  height  about  100  feet  above  the  valley,  or  1,300  feet  above  the  sea. 
Thence  northward  a  smooth  slope  ascends  50  to  60  feet,  or  in  some  por- 
tions only  30  or  40  feet,  within  the  first  quarter  or  half  of  a  mile  to  the 
west,  succeeded  beyond  by  a  moderately  rolling  surface  with  less  ascent. 

A  terrace  of  beach  sand  and  gravel,  containing  pebbles  and  cobbles 
up  to  6  inches  in  diameter,  extends  a  third  of  a  mile  from  southeast  to 
northwest,  with  a  width  of  5  to  30  rods,  in  the  northwest  quarter  of  section 
33,  Lampton,  abutting  on  the  west  flank  of  the  rolling  and  hilly  deposits 
of  till  which  make  the  east  border  of  the  Golden  Valley.  It  was  formed 
by  currents  entering  this  strait  of  Lake  Agassiz  from  the  north,  eroding  the 
bordering  hills  in  the  east  edge  of  sections  20  and  29,  and  thence  sweep- 
ing this  sand  and  gravel  southward.  It  marks  the  highest  stage  of  Lake 
Agassiz,  having  an  elevation  of  1,213  to  1,195  feet,  declining  from  north  to 
south,  and  also  sinking  1  or  2  feet  from  west  to  east  in  its  width  of  100 
to  500  feet,  being  thus  slightly  higher  along  its  verge  than  where  it  rests 
upon  the  adjoining  hilly  till.  ' 

Middle  Branch  of  Park  River  near  the  middle  of  the  south  side  of 
section  5,  Lampton,  about  3  miles  northwest  of  Edinburgh  station,  1,185 
feet  above  the  sea;  crest  of  the  south  bank  of  the  very  small  valley  of  this 
stream,  rising  to  the  flat  Golden  Valley,  1,192  feet  on  the  east  to  1,215  feet 
on  the  west.  The  Golden  Valley  here  shows  thus  a  transverse  ascent  of 
more  than  20  feet  in  its  width  of  about  1  mile.  On  the  north  line  of  sec- 
tions 5  and  6,  Lampton,  the  east  edge  of  this  valley  has  an  elevation  of 
1,210  feet,  and  its  west  edge,  1,220  feet.  About  a  half  mile  farther  north 
the  height  of  this  belt  where  it  is  crossed  by  a  tributary  of  the  Middle 
Branch  is  1,220  to  1,235  feet  from  east  to  west,  being  thus  above  the 
highest  level  of  Lake  Agassiz. 


BEACHES  AND  ISLANDS.  345 

BEACHES    AND    ISLANDS    EAST    OF    THE    ELK    AND    GOLDEN    VALLEYS. 

(PLATES   XXIX    AND    XXX.) 

Returning  about  4,5  miles  south  to  Larimore,  we  have  yet  to  describe 
the  beaches  of  Lake  Agassiz  and  its  islands  of  rolling  and  hilly  morainic 
till  which  divided  the  strait  of  the  Elk  and  Golden  valleys  in  Grand  Forks 
and  Walsh  counties  from  the  main  body  of  the  lake. 

The  crests  of  the  upper  or  first  and  the  second  Herman  beaches  before 
described,  respectively  4f  and  4^  miles  west  of  Larimore,  are  1,162  and 
1,146  feet  above  the  sea.  The  third  Herman  beach,  a  third  of  a  mile  east 
of  Larimore  depot,  has  its  crest  at  1,133  feet;  and  another  beach  belonging 
to  the  same  stage  of  Lake  Agassiz,  a  third  of  a  mile  farther  east,  rises  to 
1,134  feet,  with  descent  in  30  or  40  rods  east  11  feet,  and  in  the  same 
distance  west  9  feet.  The  fourth  Herman  beach,  consisting  of  four  small 
beach  ridges  crossed  by  the  railway  IJ  to  2  miles  east  of  Larimore,  has 
crests  at  1,123  to  1,118  feet,  with  intervening  hollows  3  to  5  feet  deep. 

The  beach  seen  two-thirds  of  a  mile  east  of  Larimore  passes  north  and 
north-northwesterly  through  the  east  half  of  sections  7  and  6,  Arvilla,  and 
the  west  half  of  sections  31  and  30,  Hegton,  into  the  southeast  corner  of 
section  24,  Elm  Grove.  North  of  the  South  Branch  of  Turtle  River  it  is 
not  a  typical  ridge,  Ijut  a  series  of  massive  rounded  swells  of  sand  10  to 
15  feet  high,  with  their  crests  at  1,135  to  1,140  feet. 

A  parallel  beach  ridge,  a  third  to  a  half  mile  west  of  the  foregoing, 
mostly  massive,  with  typical  wave-like  form,  has  an  elevation  of  1,133  feet 
close  east  of  Larimore;  1,144  feet  at  a  cemetery  close  north  of  the  South 
Branch  of  Turtle  River  in  or  near  the  southwest  corner  of  section  31,  Heg- 
ton; chiefly  1,137  to  1,140  feet  in  its  course  thence  north-northwestei-ly 
through  sections  36  and  25,  the  west  edge  of  section  24,  and  the  east  half 
of  section  14,  Elm  Grove;  1,142  to  1,145  feet  in  the  west  half  of  section 
11,  and  1,143  to  1,147  feet  in  the  east  edge  of  section  3  of  this  township. 
Along  the  west  edge  of  section  11,  a  duplication  of  this  beach  ridge,  of  the 
same  massive  size,  lying  a  half  mile  farther  west,  extends  a  mile  south  from 
the  North  Branch  of  Turtle  River,  its  crest  being  at  1,142  to  1,145  feet; 
but  thence  southward  the  general  elevation  is  aboixt  1,130  feet  to  the  broad 
tract  of  this  height  crossed  by  the  railway  west  of  Larimore,  excepting 


34B  THE  GLACIAL  LAKE  AGASSIZ. 

that  the  Soiith  Branch  of  Txirtle  River  has  eroded  a  valley  40  to  75  feet 
deep.  The  distance  of  IJ  miles  from  Larimore  north  to  this  stream  is  a 
gradually  descending,  smooth  slope,  but  its  northern  bluiF  rises  steeply  to 
a  height  a  few  feet  above  that  of  Larimore. 

Great  Northern  Railway  at  Larimore,  1,134  feet  above  the  sea;  at 
McCanna,  1,140  feet;  on  the  bridge  over  the  North  Branch  of  Turtle 
River,  1,132  feet,  17  feet  above  the  stream;  at  its  summit,  in  the  north- 
east corner  of  section  22,  Agnes,  grade  and  natural  surface,  1,164  feet;  at 
Orr's  station,  1,098  feet. 

Lower  Herman  beach,  running  northwesterly  in  the  northeast  part  of 
section  24,  Elm  Grove,  1,127  to  1,128  feet,  with  depression  of  2  to  3  feet 
on  its  Avest  side;  in  section  13,  1,127  to  1,132  feet;  in  the  west  part  of 
section  12  and  the  northeast  part  of  section  11,  1,130  to  1,135  feet,  being 
in  these  sections  the  easternmost  in  a  succession  of  three  beach  ridges,  the 
two  others  of  which  are  10  feet  higher;  at  E.  C.  D.  Shortridge's  house,  in 
the  center  of  section  2,  1,137  feet,  forming  a  broad,  flat  swell  of  sand  and 
fine  gravel,  with  a  depression  of  3  to  5  feet  on  its  west  side;  in  the  west 
part  of  section  36,  through  sections  26  and  23,  and  the  southwest  edge  of 
section  14,  Agnes,  a  continuous,  well-defined  beach  ridge,  1,140  to  1,149 
feet,  with  a  descent  of  10  to  15  feet  on  the  east  and  a  depression  of  about 
5  feet  on  the  west;  in  the  east  edge  of  the  northeast  quarter  of  section 
15  and  through  the  southeast  quarter  of  section  10,  Agnes,  a  deposit  of  sand 
and  fine  gravel,  with  iiearly  level  top  20  to  30  rods  wide,  1,145  to  1,149 
feet,  from  which  a  slope  falls  10  or  15  feet  in  20  to  30  rods  eastward,  while 
on  the  west  it  is  bordered  by  a  slough  5  to  20  rods  wide,  which  is  partly 
permanent  water  and  partly  mowing  land.  It  is  to  be  noted  that  the 
northern  two-thirds  of  the  beach  here  described  for  a  distance  of  8  miles 
con'esponds  in  elevation  with  the  two  beaches  close  east  of  Larimore  and 
with  their  continuation  northward  to  the  North  Branch  of  Turtle  River, 
marking  the  third  Herman  stage  of  Lake  Agassiz;  but  that  the  southern 
part  records  a  slightly  lower  level  of  the  lake,  when  it  had  fallen  about  10 
feet,  or  to  its  fourth  Herman  stage. 

On  the  west  side  of  this  beach  a  smoothly  undulating,  broad  swell  of 
till,  which  was  an  island  in  Lake  Agassiz,  lies  in  the  west  part  of  section  26 


HERMAN  BEACHES  NORTH  OF  LAEIMORE.  347 

and  the  east  edge  of  section  27,  Agnes,  with  a  nearly  level  top  of  several 
acres,  at  1,182  to  1,190  feet.  An  aboriginal  bnrial  mound,  raised  4  feet 
and  having  a  diameter  of  about  50  feet,  is  situated  on  the  highest  part  of 
this  area.  Such  localities,  overlooking  an  extensive  and  beautiful  pano- 
rama, were  frequent!)-  chosen  for  this  use,  as  is  shown  by  many  mounds 
on  hilltops  and  on  the  margin  of  bluffs  bordering  deeply  eroded  valleys 
throughout  the  Northwest. 

North  of  this  island  the  upper  Hemian  beach  is  represented  in  the 
east  part  of  the  southeast  quarter  of  section  22  and  in  the  west  half  of 
the  southwest  quarter  of  section  23,  Agnes,  by  a  wide  tract  of  gravel  and 
sand  deposits,  in  irregular  ridges  and  swells  rising  4  to  8  feet,  mostly 
trending  from  north  to  south,  with  their  crests  at  1,164  to  1,170  feet.  Next 
to  the  north  it  is  a  well-defined  beach  ridge,  with  crest  rising  from  1,163  to 
1,168  feet  in  its  course  of  a  half  mile  from  south  to  north  through  the  east 
edge  of  the  northeast  quarter  of  section  22. 

In  the  southeast  quarter  of  section  15,  Agnes,  the  plain  that  descends 
slowly  toward  the  Red  River  on  the  east  is  divided  from  the  Elk  Valley  on 
the  west  by  a  low  swell  of  till,  having  an  elevation  of  1,157  to  1,160  feet, 
destitute  of  beach  deposits.  This  is  succeeded  in  the  north  part  of  this 
section  and  the  south  part  of  section  10  by  a  second  island  which  rose 
above  the  highest  level  of  the  glacial  lake,  having  a  length  of  1  mile  from 
south  to  north  and  averaging  a  quarter  of  a  mile  wide,  its  elevation  in  the 
southwest  quarter  of  the  northeast  quarter  of  section  15  being  about  1,187 
feet,  on  the  line  between  these  sections  about  1,175  feet,  and  near  the  cen- 
ter of  section  10,  at  the  north  end  of  this  irregular  ridge,  about  1,180  feet. 
Its  material  is  till,  partially  overspread  in  its  south  half  by  gravel,  which 
seems  to  have  been  brought  by  the  currents  and  waves  of  Lake  Agassiz 
from  the  erosion  of  its  northern  portion. 

The  beach  of  Lake  Agassiz  during  its  highest  stage  extends  north 
from  the  north  end  of  this  island  into  the  southwest  quarter  of  section  3, 
Agnes,  where  it  is  a  ridge  about  20  rods  wide,  with  an  elevation  of  1,165 
to  1,172  feet,  composed  of  coarse  gravel  and  sand,  inclosing  plentiful  rock 
fragments,  chiefly  granitic,  up  to  6  inches  in  diameter,  most  of  which  are 
only  very  slightly  waterworn.     Its  eastern  slope  descends  15  to  20  feet  in 


348  THE  GLACIAL  LAKE  AGASSIZ. 

as  many  rods,  and  on  the  west  an  equal  descent  takes  place  within  8  or  10 
rods.  The  steep  western  slope  of  this  beach  or  bar,  forming  the  east  rim 
of  the  strait  that  filled  the  Elk  Valley,  was  due  to  storms  on  the  broad 
lake,  rolling  its  Avaves  upon  the  bar  and  carrying  the  sand  and  coarse 
gravel  upward  and  over  its  crest.  Turning  northwestward,  this  beach 
passes  into  the  northeast  quarter  of  section  4,  where  it  consists  of  irregular 
accumulations  of  gravel  and  sand,  occupying  a  width  of  an  eighth  to  a 
fourth  of  a  mile,  with  their  crests  at  1,155  to  1,162  feet.  In  the  north 
edge  of  section  4  it  again  becomes  a  definite  beach  ridge  of  the  same 
material  and  contom-  as  in  section  3,  and  thus  passes  northeast  and  north 
tlu-ough  section  33,  Inkster,  with  its  crest  mostly  at  1,165  to  1,172  feet,  its 
lowest  part,  about  1,162  feet,  being  near  the  center  of  the  section.  The 
two  islands  before  described,  this  beach  or  bar,  and  the  long  island  next 
northward  are  together  commonly  called  "The  Ridge,"  being  the  eastern 
limit  of  the  Elk  Valley,  which  averages  4  miles  wide,  1,150  to  1,140  feet 
above  the  sea  in  its  eastern  and  central  portions,  but  rising  with  a  trans- 
verse slope  to  1,160  feet  on  its  western  border. 

A  third  island  above  the  highest  stage  of  Lake  Agassiz,  3  miles  long 
from  south  to  north  and  a  quarter  to  a  half  mile  wide,  varying  in  elevation 
along  its  highest  part  from  1,170  to  1,223  feet,  reaches  tlu'ough  sections 
28  and  21,  the  west  half  of  section  16,  and  into  the  southwest  corner  of 
section  9,  Inkster.  It  is  till,  with  somewhat  uneven  surface,  bearing  fre- 
quent bowlders.  Beach  deposits  occur  on  the  east  flank  of  this  island  in 
section  21  at  1,155  to  1,165  feet,  and  from  1,155  feet  a  smooth  slope  of 
sand  and  fine  gravel  falls  slowly  eastward  along  the  east  side  of  this 
highland  through  the  greater  part  of  its  extent. 

In  the  southeast  part  of  section  8,  Inkster,  irregular  accumulations 
of  beach  gravel,  with  crests  at  1,170  to  1,175  feet,  10  to  15  feet  above 
the  adjoining  depressions  of  till,  extend  northward  from  the  island  just 
described;  and  in  the  north  part  of  this  section  8  the  beach  sinks  within  an 
eighth  of  a  mile  from  1,172  to  1,161  feet  and  changes  to  a  broad,  smooth 
ridge,  which  thence  passes  northward  through  section  5  of  this  township, 
in  which  it  is  intersected  by  the  Forest  River,  and  through  the  west  half 
of  section  32,   Eden,  near  the   center  of  which  it  has   tln-ee  aboriginal 


"THE  RIDGE"  AND  "THE  MOUNTAINS."  349 

mounds,  6  to  8  feet  in  lieight,  on  its  top.  The  material  of  tliis  beach  ridge 
is  fine  gravel  and  sand.  Its  crest  on  the  line  between  sections  8  and  5  has 
an  elevation  of  1,161  feet;  an  eiglith  of  a  mile  north,  at  the  verge  of  the 
south  bluff  of  Forest  River,  1,155  feet ;  for  the  first  half  mile  from  the  bluff 
north  of  this  river,  1,152  to  1,157  feet;  and  at  the  mounds  in  section  32, 
1,156  to  1,159  feet. 

Another  beach  ridge,  20  rods  wide,  with  descent  of  10  feet  on  each 
side  in  as  many  rods,  formed  during  the  same  stage  of  Lake  Agassiz,  lies 
a  half  to  three-fourths  of  a  mile  west  from  the  foregoing,  in  the  northeast 
quarter  of  section  6,  Inkster.  This  is  the  highest  land  between  the  main 
Forest  River  and  its  South  Branch.  It  consists  of  sand  and  fine  gravel,  of 
which  a  considerable  proportion  (about  a  sixth)  is  Cretaceous  shale.  The 
maximum  elevation  of  this  ridge,  1,157  to  1,164  feet,  is  maintained  for 
50  or  60  rods,  from  which  it  sinks  to  1,150  feet  at  each  end. 

From  the  north  side  of  section  32,  Eden,  an  island  of  rolling  and  hilly 
morainic  till  above  the  highest  level  of  Lake  Agassiz,  far  larger  than 
any  of  these  already  described,  extends,  with  the  exception  of  two  short 
gaps,  20  miles  northward,  varying  in  width  from  a  half  mile  to  a  little 
more  than  1  mile  in  its  southern  quarter  and  from  1^  to  2^  miles  tlu'ough 
the  remainder  of  its  extent.  This  hilly  tract,  commonly  denominated  "the 
mountains,"  forms  the  east  border  of  the  Golden  Valley.  In  the  north 
part  of  section  36,  Vernon,  it  has  a  depression  to  about  1,180  feet,  which 
probably  was  a  strait  of  the  glacial  lake  in  its  highest  stage,  an  eighth  of 
a  mile  wide  and  a  few  feet  deep.  Again,  in  the  center  of  Golden  Town- 
ship, it  is  intersected  by  the  South  Branch  of  Park  River,  which  has  a 
valley  a  quarter  to  a  half  of  a  mile  wide  and  about  75  feet  deep.  The 
stream  in  its  course  of  IJ  miles  through  this  belt  descends  about  50  feet, 
from  1,165  to  1,115  feet,  approximately.  It  seems  almost  certain  that  a 
depression  slightly  lower  than  the  Golden  Valley  on  the  west  originally 
extended  across  this  I'olling  and  hilly  area  where  it  is  cut  by  this  stream ; 
but  the  erosion  of  its  valley  has  undermined  and  removed  portions  of 
adjoining  hills  and  ridges,  so  that  its  inclosing  bluffs  now  I'ise  50  to  100 
feet,  their  highest  points  being  about  1,225  feet  above  the  sea,  or  25  to 
30  feet  above  the  east  edge  of  the  Golden  Valley.     All  these  bluffs  and 


350  THE  GLACIAL  LAKE  AGASSIZ. 

two  plateaus  left  in  the  midst  of  the  valley  are  till,  yellowish  near  the  top 
and  dark-bluish  below. 

The  elevation  of  "the  mountains"  in  their  southern  and  narrower 
portion,  tlu-ough  the  west  part  of  Eden  and  the  northeast  corner  of  Med- 
ford,  is  1,190  to  1,225  feet;  through  the  east  hah"  of  Vernon,  1,200  to 
1,250  feet;  in  the  south  part  of  Golden,  1,200  to  1,260  feet,  and  tlu-ough 
the  north  half  of  this  township  and  the  south  half  of  Lampton,  1,200  to 
1,275  feet,  being  highest  in  section  28  of  the  township  last  named,  near 
the  northern  end  of  this  hilly  tract.  These  prominent  accumulations  of 
till,  rising  in  the  west  edge  of  the  lacustrine  area,  seem  referable,  as  shown 
in  Chapter  IV,  to  the  ninth  or  Leaf  Hills  moraine.  They  appear  to  have 
been  formed  on  the  western  margin  of  the  Minnesota  lobe  of  the  ice-sheet. 
The  east  border  of  "the  mountains,"  in  section  20,  Eden,  falls  some- 
what steeply  to  about  1,135  feet,  and  thence  a  flat  slope,  with  no  beach 
ridges,  sinks  slowly  eastward.  In  the  northeast  quarter  of  section  7  in 
this  township  a  well-defined  beach  ridge  10  to  15  rods  wide,  composed  of 
sand  and  gravel,  with  pebbles  up  to  2  or  3  inches  in  diameter,  extends  25 
rods  south  from  an  eastern  spur  of  the  hilly  till ;  crest  of  this  spur,  about 
1,195  feet;  of  the  beach,  1,172  feet,  with  depression  of  3  to  6  feet  on  the 
west.  Irregular  beach  accumulations,  10  to  20  feet  lower,  continue  south- 
ward nearly  a  half  mile. 

In  section  30,  Rushford,  the  eastern  border  of  this  rolling  and  hilly 
area  falls  75  feet  or  more  within  a  third  of  a  mile,  to  about  1,100  feet.  Its 
material  is  till,  with  scanty  deposits  of  beach  gravel  and  sand,  not  distinctly 
accumulated  in  ridge  form.  About  half  way  down  this  slope  it  shows  in 
some  places  a  more  abrupt  escarpment,  with  steep  descent  of  15  or  20  feet. 
The  same  features  continue  through  section  19,  except  that  a  series  of  dis- 
tinct beach  deposits  is  observable  about  25  rods  east  from  the  crest  of  the 
slope,  at  1,170  to  1,175  feet,  probably  formed  during  the  second  Herman 
stage  of  Lake  Agassiz.  A  descent  of  125  feet  takes  place  within  a  half 
mile  on  the  east  side  of  "the  mountains,"  near  where  it  is  cut  by  a  large 
but  short  ravine,  in  the  southeast  quai-ter  of  section  12,  Vernon,  falling 
from  1,180  to  1,050  feet,  approximately,  with  no  well-defined  shore-hnes 
observable.     A  grove  lies  at  the  east  base  of  this  slope  a  third  of  a  mile 


HERMAN  BEACHES  NEAR  PARK  RIVER.  351 

south  of  the  ravine.  In  the  northwest  quarter  of  this  section  12  and  the 
west  edge  of  the  southwest  quarter  of  section  1,  a  well-developed  beach, 
in  part  consisting  of  two  parallel  low  ridges,  has  an  elevation  of  1,170  to 
1,177  feet,'  and  in  the  east  edge  of  section  2,  continuing  northward,  its 
elevation  is  1,177  to  1,184  feet.  Its  eastern  slope  falls  to  1,170  feet  within 
10  or  20  rods. 

Great  Northern  Railway  at  Park  River  depot,  998  feet  above  the  sea; 
natural  surface  at  the  southeast  corner  of  section  23,  Golden,  on  the  road 
leading  west  from  Park  River,  1,178  feet.  The  crest  of  the  upper  Her- 
man beach,  crossed  by  this  road  10  rods  west  from  the  point  named,  is  at 
1,187  feet,  but  20  rods  southeast  and  northwest  from  the  road  its  height  is 
1,192  feet.  This  is  a  typical  beach  ridge  of  sand  and  gravel,  with  pebbles 
up  to  2  or  3  inches  in  diameter,  mostly  limestone  and  granite.  The  Creta- 
ceous shale  before  mentioned  is  very  rare  in  the  till  of  "the  mountains" 
and  in  the  beaches  formed  along  their  east  side,  indicating  that  the  east 
limit  of  this  shale  is  the  Pembina  Mountain  and  the  western  ascent  of  the 
Golden  Valley,  and  that  the  glacial  currents  by  which  the  drift  here  was 
deposited  came  only  from  the  north  and  northeast,  with  no  intermixture  of 
currents  from  west  of  north. 

Highest  beach  on  verge  of  south  bluif  of  the  South  Branch  of  Park 
River,  in  the  southeast  quarter  of  section  23,  Golden,  1,188  to  1,192  feet, 
with  a  basin-shaped  hollow  on  its  west  side  20  feet  lower,  which  changes 
southward  to  a  depression  of  about  5  feet.  The  river  bluff  is  here  freshly 
undermined,  showing  the  depth  of  the  beach  sand  and  gravel  to  be  5  to  10 
feet,  lying  on  till.  Lower  beach,  a  quarter  of  a  mile  farther  east,  extending 
from  northwest  to  southeast,  in  the  southwest  quarter  of  section  24,  1,167 
to  1,170  feet. 

Lower  Herman  beach,  a  massive  ridge  of  gravel  and  sand,  extending 
in  a  curved  course  convex  toward  the  east  from  the  northeast  quarter  of 
section  2,  Golden,  through  the  southeast  part  of  section  35,  Lampton,  crest, 
1,160  to  1,165  feet;  through  the  northeast  edge  of  section  36  and  the  south- 
west comer  of  section  25,  40  to  50  rods  wide,  with  slightly  undulating 
surface,  1,160  to  1,167  feet;  near  the  middle  of  the  east  side  of  the  south- 


352  THE  GLACIAL  LAKE  AGASSIZ. 

east  quarter  of  section  26,  1,165  to  l,l66  feet;  and  at  the  quarter-section 
stake  on  the  north  side  of  this  section  26,  1,163  feet. 

Near  the  west  Kne  of  section  23,  Lampton,  two  Herman  beaches  abut 
upon  the  east  flank  of  the  north  end  of  "the  mountains,"  and  extend  thence 
north-northwesterly  2  miles  to  the   Middle  Branch  of  Park  River.     The 
eastern  one,  a  well-defined  ridge  of  sand  and  fine  gravel,  passes  close  west 
of  the  quarter-section  stake  between  sections  15  and  10.     The  elevation  of 
its  crest  is  1,161  to  1,166  feet,  with  increase  in  height  from  south  to  north; 
the  descent  on  the  east  is  15  or  20  feet  in  as  many  rods,  and  the  depression 
on  the  west  is  3  to  8  feet  deep  and  10  rods  wide.     The  other  beach  ridge  is 
40  or  50  rods  farther  west,  parallel  with  the  preceding  and  similar  in  form 
and  material;  its  crest,  rising  slightly  northward,  is  at  1,173  to  1,176  feet. 
Another  distinct  beach  lidge,  but  of  smaller  size,  runs  in  a  parallel  course 
through  the  east  part  of  the  southwest  quarter  of  section  9,  with  its  crest 
at  1,185  to  1,187  feet.     These  appear  to  represent  together  the  thu-d  and 
second  Herman  beaches  of  the  series  observed  northwest  of  Maple  Lake  in 
Minnesota  and  east  and  west  of  Larimore.     The  lowest  Herman  beach 
in  this  vicinity  passes  as  a  well-marked  ridge  of  gravel  and  sand  tlirough 
the  west  part  of  sections  11  and  2,  Lampton,  and  the  east  part  of  sections 
34,  27,  and  22,  Gardar,  having  a  height  of  1,145  to  1,150  feet,  from  which 
there  is  a  descent  of  5  to  10  feet  on  the  east  and  half  as  much  on  the  west. 
Upper  Herman  beach,  northward  from  the  north  end  of  "the  moun- 
tains," forming  in  the  northwest  quarter  of  section  21  and  the  west  part  of 
section  16,  Lampton,  a  massive  broad  ridge,  composed  of  sand  and  gravel, 
with  pebbles  up  to  4  or  even  6  inches  in  diameter,  crest,  1,197  to  1,207 
feet  rising  highest  northward,  where  the  beach  deposit  overlies  the  eastern 
slope  of  a  wave-like  swell  of  till  that  rises  to  1,212  feet.     Small  beach 
ridge,  belonging  to  this  stage,  in  the  east  edge  of  the  southeast  quarter  of 
section  8,  Lampton,  1,202  to  1,207  feet.     Surface  at  Evan  Edwards's  house, 
in  the  west  part  of  the  southwest  quarter  of  section  9,  1,197  feet,  consisting 
of  sand  and  gravel  of  this  beach  to  a  depth  of  10  feet,  underlain  by  till, 
yellowish  in  its  first  6  feet  and  dark-bluish  below.     Summit  of  a  smoothly 
rounded  hillock,  probably  till,  but  having  few  or  no  bowlders,  in  the  east 
edge  of  the  northeast  quarter  of  section  8,  about  1,230  feet;  train  of  beach 


HEEMAN  BEACHES  NEAK  GARDAE.  353 

gravel  and  sand  extending  thence  30  rods  southward,   1,217  feet,  with 
descent  of  15  or  20  feet  on  each  side. 

Continuing  beyond  the  Middle  Branch  of  Park  River,  this  highest 
beach  is  well  developed  in  a  broad  ridge  running  due  north  through  the 
west  part  of  section  4,  Lampton,  with  its  crest  at  1,202  to  1,208  feet.  On 
the  east  the  surface  falls  30  or  40  feet,  and  more  slowly  beyond,  while 
toward  the  west  a  descent  of  10  feet  is  succeeded  by  a  flat  surface  of  till, 
which  rises  slowly  from  the  foot  of  the  beach  ridge  to  a  swell  at  the  heiglit 
of  1,215  to  1,225  feet,  a  half  mile  away,  forming  the  east  boundary  of  the 
Golden  Valley.  This  beach  is  sand  and  gravel,  with  pebbles  up  to  6  inches 
in  diameter.  About  half  of  them  are  limestone;  nearly  all  of  the  remain- 
der are  Archean  granite,  gneiss,  and  schists;  scarcely  one  in  two  hundred 
is  Cretaceous  shale.  Through  the  west  edge  of  section  33,  Gardar,  the 
elevation  of  this  excellent  beach  ridge  is  1,202  to  1,205  feet,  and  in  the 
southwest  edge  of  section  28  and  the  middle  of  the  east  edge  of  section 
29,  1,202  to  1,197  feet,  decreasmg  in  height  and  size  northward.  For  a 
half  mile  through  the  southwest  quarter  of  section  33,  a  slight  secondary 
beach  ridge,  4  to  9  feet  lower,  lies  about  30  rods  east  from  the  foregoing; 
its  crest  is  at  1,198  to  1,195  feet,  sinking  a  few  feet  from  south  to  north; 
it  is  divided  from  the  higher  beach  by  a  continuous  depression  about  3 
feet  deep. 

A  very  massive  beach  ridge,  composed  of  sand  and  gravel,  with  peb- 
bles and  rock  fragments,  the  largest  only  slightly  waterworn,  up  to  6 
inches  in  diameter,  passes  a  few  degrees  west  of  north  through  the  center 
of  section  20,  Gardar,  its  crest  in  the  south  half  of  the  section  being  at 
1,208  to  1,215  feet,  and  in  the  north  half  1,215  to  1,223  feet.  On  the 
east  is  a  descent  of  20  to  30  feet  within  25  to  40  rods,  and  on  the  west  10 
or  12  feet  from  the  highest  part  of  the  beach  within  10  rods  to  a  nearly 
level  area  of  till,  1,211  feet,  which  sinks  40  rods  farther  west  to  a  long 
slough,  about  1,205  feet,  parallel  with  the  beach  and  a  sixth  of  a  mile  wide. 
Beyond  this  an  undulating  surface  of  till,  partly  covered  with  bushes  and 
small  trees,  rises  to  1,250  or  1,275  feet  within  2  miles,  and  then  in  smooth, 
massive  swells  to  1,450  or  1,500  feet  within  the  next  2  to  4  miles.  These 
are  part  of  a  plateau,  thence  rising  more  slowly  westward,  whose  boundary 
MON  XXV 23 


354  THE  GLACIAL  LAKE  AGASSIZ. 

for  the  next  75  miles  to  the  north-northwest  is  the  conspicuous  escarpment 
called  Pembina  Mountain. 

The  north  end  of  this  massive  beach  bears  on  its  crest  an  artificia 
embankment  100  feet  long  from  east  to  west  and  20  feet  wide,  raised  2  feet 
above  the  natvn-al  surface,  its  top  being  1,225  feet  above  the  sea.  This  is 
10  rods  south  from  where  the  beach  is  cut  to  1,210  feet  by  a  wide  gap,  as 
of  some  ancient  watercourse.  In  the  south  edge  of  the  southwest  quar- 
ter of  section  17,  Gardar,  on  the  south  bank  of  the  North  Branch  of  Park 
River,  about  10  rods  east  from  the  ford  of  the  "Half-breed  road,"  this  beach 
has  an  elevation  of  1,220  feet. 

North  Branch  of  Park  River  at  this  ford,  10  to  15  feet  wide  and  a  few 
inches  deep,  1,203  feet.  Surface  at  the  village  of  Gardar,  a  mile  east, 
1,175  to  1,170  feet.  Lower  Herman  beach,  passing  from  south  to  north 
along  the  east  side  of  sections  20  and  17,  Gardar,  a  thu'd  of  a  mile  west  of 
the  village,  about  1,185  feet. 

FROM  GARDAR  NORTH  TO  THE  TONGUE  RIVER. 

(PLATE   XXX.) 

Sections  17,  8,  and  5,  Gardar,  rise  from  1,190  and  1,200  feet  on  their 
east  side  to  1,220  and  1,225  feet  on  the  west,  including,  therefore,  the 
upper  Herman  shore  of  Lake  Agassiz;  but  they  present  no  considerable 
deposits  of  beach  gravel  and  sand.  A  swell  of  till,  sprinkled  with  very 
abundant  bowlders,  nearly  all  Archean  granite  and  gneiss,  up  to  5  feet  in 
diameter,  extends  from  south  to  north  across  the  line  between  sections  8 
and  5,  having  its  crest  at  1,215  feet,  from  which  there  is  a  steep  descent  of 
10  or  12  feet  to  the  west.  Sloughs  and  pools  of  water,  permanent  through 
the  year,  he  in  the  west  part  of  section  5,  about  1,190  feet  above  the  sea. 

The  South  Branch  of  Cart  Creek,  in  sections  31  and  32,  Thingvalla, 
is  bordered  by  a  belt  of  timber  a  half  mile  wide,  but  it  has  only  a  small 
channel  a  few  feet  below  the  general  surface,  and  is  dry  tlu'ough  the  greater 
part  of  the  year.  Its  alluvial  gravel,  like  that  of  the  Middle  and  North 
branches  of  Park  River,  is  mostly  Cretaceous  shale,  derived  from  the 
gorges  eroded  in  this  rock  at  the  sources  of  these  streams  in  the  Pembina 
Mountain. 


us.  GEOLOGICAL  SURVEY. 


MONOGRAPH  XXV.    PL.  XXX 


MAP  OF  THE  WTISTERX  SHOIiES  OF  LAKE  AGASSIZ,  INCLIIDLXG  THE  PEMOINADKLTA.FKOM  l'AIU(  rmTH.WALSII  COrXT^'. 
NORTH  TIUWlTGHl'EMBroAx\OT)  CAVALIER  COUNTIES.NORTH  DAKOTA.  TO  THE  LN'TEIWATIONAL  BOUNDARY. 

Scale.  (Wiiilps  to  ail  inch. 


Lake  x\j-ea    I I  Delia     I 1  Moraines  l_ 

Alfittu/es  of    R<iilw((v  .sOt/toTiA-  arc    /loted    in    f'rvt    above  t/ir   srti  . 


HBEMAN  BEACHES  ALONG  PEMBINA  MOUNTAIN.  355 

Along  the  western  border  of  Lake  Agassiz  here  and  northward  into 
Manitoba  extends  a  prominent  wooded  bkifF,  the  escarpment  of  a  treeless 
plateau  which  from  its  crest  stretches  with  slow  ascent  westward.  This 
escarpment,  commonly  called  the  Pembina  Mountain  (described  in  pages 
40-42,  93-97),  is  a  very  marked  feature  in  the  topography  for  about  75 
miles.  It  is  caused  by  the  outcrop,  mostly  overspread  by  glacial  drift,  of  a 
continuous  belt  of  nearly  horizontal  Cretaceous  shale,  several  hundred  feet 
thick,  usually  so  hard  and  enduring  that  it  is  popularly  termed  "slate" 
Its  course  coincides  nearly  with  the  west  line  of  Gardar  and  Thingvalla 
townships.  Thence  it  continues  in  an  almost  straight  course,  a  few  degi'ees 
west  of  north,  to  the  international  boundary,  beyond  which  it  runs  north- 
northwest  nearly  50  miles  to  the  vicinity  of  Treherne.  The  base  of  the 
ascent  is  about  1,225  feet  above  the  sea,  and  its  crest  approximately  1,500 
feet,  northward  to  the  Pembina  River,  beyond  which  the  base  sinks  to 
1,150  and  1,100  feet  and  the  crest  to  1,400  and  1,300  feet.  The  width 
occupied  by  the  slope  varies  from  a  quarter  to  a  half  of  a  mile. 

Natural  surface  at  the  quarter-section  stake  on  the  north  side  of  section 
32,  Thingvalla,  1,178  feet  above  the  sea.  Sections  32,  29,  and  20  of  this 
township  are  mostly  till,  smoothed  by  this  glacial  lake,  the  depressions  hav- 
ing been  filled  by  leveling  down  the  higher  portions,  where  many  bowlders 
partially  embedded  testify  of  considerable  erosion.  A  broad  ridge  of  beach 
sand  and  fine  gravel  3  to  5  feet  high  extends  from  south  to  north  tluough 
the  center  of  section  29,  its  crest  being  at  1,180  to  1,182  feet.  This  is  the 
thud  in  the  series  of  four  Herman  beaches  observed  near  Maple  Lake,  near 
Larimore,  and  in  Lampton.  The  higher  beaches  are  probably  also  recog- 
nizable 1  to  1 J  miles  farther  west,  near  the  base  of  the  Pembina  escarpment 
or  "second  mountain,"  which  is  1,220  to  1,230  feet  above  the  sea;  but  it 
is  impracticable  to  trace  their  course  and  determine  their  exact  elevation, 
because  woods  reach  from  the  base  of  this  escarpment  a  half  mile  east, 
where  these  beaches  belong. 

Fourth  Herman  beach,  a  broad,  low  swell  of  sand  and  gravel,  extending 
uorth-northwesterly  through  the  east  half  of  section  20,  Thingvalla,  1,166  to 
1,172  feet;  through  sections  17  and  8,  an  eighth  to  a  quarter  of  a  mile  wide, 
1,161  to  1,173  feet,  having  in  some  places  a  depth  of  at  least  10  feet,  as 


356  THE  GLACIAL  LAKE  AGASSIZ. 

shown  by  wells.  On  the  north  line  of  section  20,  and  again  in  the  north 
part  of  section  17,  it  is  intersected  by  branches  of  Cart  Creek,  which  occupy 
valleys  about  40  feet  deep  and  an  eighth  to  a  quarter  of  a  mile  wide. 
Brush  and  scattered  trees  grow  in  these  valleys  and  on  the  area  between 
them.  Toward  the  east  a  descent  of  30  or  40  feet  is  made  within  the  first 
half  mile;  westward  there  is  only  a  slight  ascent,  to  about  1,200  feet,  in  1 
mile;  then  a  more  considerable  slope,  covered  with  Avoods,  rises  20  to  40 
feet  to  the  base  of  the  "second  mountain,"  on  or  near  the  township  line. 

In  the  west  part  of  section  8,  and  again  near  the  northeast  corner  of 
section  6,  Thingvalla,  this  beach  is  intersected  by  the  head  streams  of  Wil- 
low Creek,  in  valleys  about  35  feet  deep.  On  the  north  line  of  sections  5 
and  6  of  this  township  the  fourth  and  third  Herman  beaches  are  merged 
in  an  undulating  tract  of  gravel  and  sand  a  half  mile  wide,  which  rises 
from  1,160  feet  on  the  east  to  1,184  feet  on  the  west.  A  well  on  the  west 
part  of  this  belt  found  the  beach  deposit  6  feet  thick,  underlain  by  till, 
which  forms  the  slightly  ascending  surface  next  west. 

Base  of  the  second  Pembina  Mountain,  in  the  east  half  of  section  31, 
township  161,  range  56,  1,235  feet  at  the  south  to  1,220  feet  northward, 
coinciding  nearly  with  the  upper  Herman  shore  of  Lake  Agassiz.  William 
Crombie's  well,  24  feet  deep,  near  the  center  of  section  30,  situated  about 
50  feet  above  the  Tongue  River,  a  few  rods  back  from  the  verge  of  its  north 
bluff,  was  soil,  2  feet;  gravel,  nearly  all  Cretaceous  shale,  8  feet;  underlain 
by  gravel,  nearly  all  granite  and  gneiss,  with  scarcely  any  intermixtm-e  of 
shale,  containing  pebbles  and  cobbles  up  to  4  inches  in  diameter,  14  feet, 
yielding  a  permanent  supply  of  water.  This  well  is  close  to  the  base  of 
the  "mountain,"  at  an  elevation  of  about  1,230  feet.  Its  bed  of  granite 
gravel  appears  to  be  the  upper  beach,  the  overlying  shale  gravel  being  a 
delta  deposit  brought  by  the  Tongue  River. 

Surface  at  Young  post-oflfice,  in  the  northeast  corner  of  the  southwest 
quarter  of  section  32,  township  161,  range  56,  1,192  feet.  The  well  here, 
14  feet  deep,  is  wholly  stratified  gravel  and  sand,  being  a  beach  deposit  of 
the  second  and  third  stages  in  the  Herman  series.  Third  beach,  about  an 
eighth  of  a  mile  east  of  Young  post-office,  a  broad  ridge  of  sand  and  fine 
gravel,  a  few  feet  above  the  land  on  its  west  side,  crest,  1,187  feet.     Fourth 


THE  PEMBINA  DELTA.  357 

and  lowest  Herman  beach,  of  similar  form  with  the  last,  but  larger,  running 
a  few  degrees  west  of  north  through  the  west  edge  of  section  33,  1,173  to 
1,175  feet,  with  depression  of  1  to  5  feet  on  its  west  side  and  descent  of 
25  feet  within  30  or  40  rods  east. 

Tongiae  River,  at  bridge  near  the  center  of  the  south  half  of  section  28, 
township  lf51,  range  56,  about  1,110  feet;  bottom  land,  10  feet  higher;  top 
of  the  bluffs,  about  1,150  feet.  Gavins  reek,  in  the  south  half  of  section 
20,  about  1,140  feet;  valley,  40  feet  deep,  a  sixth  of  a  mile  wide. 

The  lowest  Herman  beach  forms  a  massive  ridge  of  sand  and  fine 
gravel  in  the  northeast  quarter  of  section  29  and  the  east  part  of  sections 
20  and  17,  township  IGl,  range  56,  with  its  crest  at  1,175  to  1,180  feet. 

DELTA    OF    THE    PEMBINA    RIVER. 

(PLATE   XXX.) 

The  largest  tributary  to  the  Red  River  in  North  Dakota  is  the  Pembina 
River,  which  has  cut  a  valley  about  400  feet  deep  and  a  mile  wide  in  the 
plateau  of  the  second  Pembina  Mountain.  During  the  recession  of  the  ice- 
sheet  this  stream  was  much  larger  than  now,  being  for  a  time  the  outlet  of 
glacial  lakes  in  the  basins  of  the  Souris  and  Saskatchewan  rivers.'  The 
delta  deposited  in  the  margin  of  the  glacial  Lake  Agassiz  by  the  Pembina 
River,  swollen  by  a  great  affluent  from  the  melting  ice-fields  at  the  north- 
west, beyond  the  present  limits  of  its  basin,  extends  about  16  miles  from 
south  to  north  and  has  an  average  width  of  about  5  miles,  with  a  maximum 
width  of  7J  miles  and  a  maximum  thickness  exceeding  200  feet.  Its  mean 
thickness  is  probabl}'  not  less  than  150  feet,  giving  for  its  volume  about  2t^ 
cubic  miles,  spread  upon  an  area  of  80  square  miles.  Four-fifths  of  this 
delta  lie  south  of  the  Pembina  River,  reaching  nearly  to  the  Tongue  River. 
Fig.  15  shows  a  section  across  this  delta  from  east  to  west  about  3  miles 
south  of  Walhalla. 

Its  elevation  in  the  northwest  part  of  section  17,  township  161,  range 
56,  is  1,200  feet;  thence  northward  it  rises  slowly  in  2  miles  to  1,225  feet 
in  the  east  part  of  section  6;  and  in  sections  31  and  30,  township  162,  range 

'Pages  267-274,  foregoing.  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Ninth  A.nnual  Report, 
for  1880,  p.  342.  Hind's  Report  of  the  Assiniboine  and  Saskatchewan  Exploring  Expedition,  1859,  pp. 
118  and  168. 


358 


THE  GLACIAL  LAKE  AGASSIZ. 


56,  it  varies  from  1,220  to  1,227  feet.  From  this  crest  of  the  southern  part 
of  the  delta  it  slopes  slowly  east  and  northeast  to  1,080  and  1,090  feet  at 
its  eastern  border,  in  sections  25,  24,  and  13,  which  coincides  neai'ly  with 
the  east  line  of  this  township  1G2,  range  56.  Deep  valleys,  with  frequent 
tributary  ravines,  have  been  eroded  in  it  by  several  small  streams.  West- 
ward the  delta  reaches  to  the  base  of  the  second  Pembina  Mountain,  the 
belt,  a  half  mile  to  1  mile  wide,  next  beyond  the  crest,  only  about  5  feet 
lower,  being  a  very  flat,  beautiful  prairie,  which  rises  slowly,  like  the  crest, 
from  south  to  north.  The  elevation  of  this  belt  in  section  18,  township 
161,  range  56,  is  1,190  to  1,195  feet,  and  at  Mr.  Henry  GrofF's  house,  in  the 
middle  of  the  east  edge  of  section  36,  township  162,  range  57,  1,221  feet. 
Farther  west  there  is  an  ascent  to  about  1,240  feet  at  the  base  of  the  "sec- 

/5£j$^_^co/70'  femb/ha  Afoon'fs/n  t;  2  •» 

?^ 


Fig.  15. — Section  across  the  delta  of  the  Pembina  River.    Horizuut:il  scale,  2  miles  to  an  inch. 

ond  mountain."  Wells  on  this  area  penetrate  only  beds  of  sand  and  gravel, 
easy  to  dig  and  needing  to  be  curbed  to  prevent  caving.  A  large  propor- 
tion, probably  half,  of  the  gravel  is  Cretaceous  shale.  Water  is  obtained 
at  depths  varying  from  25  to  60  feet. 

The  pai-t  of  the  Pembina  delta  thus  far  described  is  divided  from  its 
central  and  higher  part,  which  is  crossed  by  the  section  of  fig.  15,  by  a 
depression  about  a  mile  wide,  through  which  a  portion  or  the  whole  of  the 
river  flowed  during  much  of  the  time  while  this  delta  was  being  formed. 
In  the  southwest  corner  of  section  18,  township  162,  range  56,  this  depres- 
sion is  1,205  feet  above  the  sea,  being  20  feet  lower  than  the  area  on  the 
south.  It  extends  eastward  with  a  slow  descent  and  rises  westward  to 
1,215  feet  close  east  of  the  Little  Pembina  River,  in  section  15,  township 
162,  range  57.     This  stream  flows  tlu'ough  the  escarpment  of  the  "second 


THE  PEMBINA  DELTA.  359 

mountain,"  in  the  sontheast  quarter  of  section  22,  about  a  mile  south  from 
this  lowest  part  of  the  divide  on  its  east  side.  It  here  turns  abruptly  from 
its  eastern  course,  and  tlience  flows  north-northwest  along  the  base  of  the 
"second  mountain"  to  its  junction  with  the  Pembina  River,  thus  leaving 
the  depression  just  described,  which  would  seem  to  be  its  more  natural 
course,  and  taking  in  its  stead  a  channel  that  is  eroded  tlu'ough  a  portion  of 
the  delta  50  feet  higher. 

The  most  elevated  point  of  this  delta,  as  it  now  remains,  is  about 
1,270  feet  above  the  sea,  near  the  northwest  corner  of  section  11,  township 
162,  range  57,  east  of  the  Little  Pembina  and  south  of  the  Pembina  River, 
and  is  nearly  300  feet  above  the  junction  of  these  streams,  IJ  miles  distant 
toward  the  northwest.  Section  12  of  this  township  and  the  west  part  of 
section  7,  township  162,  range  56,  slope  from  1,225  feet  on  the  south  to 
1,215  feet  on  the  north;  their  southern  part  is  the  highest  land  crossed 
between  the  depression  before  mentioned  and  the  Pembina  River  by  the 
line  dividing  these  townships.  The  level  of  Lake  Agassiz  in  its  highest 
stage  here  was  1,220  or  1,225  feet  above  the  sea,  being  50  feet  below  the 
top  of  the  Pembina  delta,  as  is  shown  by  the  beach  line  of  this  level,  1,226 
feet,  in  the  central  part  of  this  section  7,  where  an  eastward  descent  begins. 
This  is  the  east  verge  of  the  nearly  flat  area  of  the  delta  in  sections  12  and 
7.  Like  all  of  this  delta  deposit,  the  material  here  is  sand  and  gravel,  cov- 
ered by  a  fertile  soil.  A  small  proportion  of  the  pebbles  of  this  gravel  is 
limestone;  a  large  part  is  Cretaceous  shale;  but  more  was  derived  from 
Archean  formations  of  granite  and  gneiss. 

The  second  Herman  beach,  a  ridge  of  the  usual  form,  is  crossed  by  the 
road  near  the  east  side  of  the  northeast  quarter  of  section  7,  township  162, 
range  56,  descending  from  1,212  feet  to  about  1,200  feet  in  a  distance  of  a 
third  or  half  of  a  mile  from  south  to  north. 

William  Roadhouse's  well,  110  feet  deep,  in  the  northwest  quarter  of 
section  8,  township  162,  range  56,  at  the  elevation  of  1,184  feet,  is  all  strat- 
ified sand  and  gravel,  with  pebbles  up  to  6  inches  in  diameter,  fully  half 
Cretaceous  shale.  Water  comes  in  coarse  sand  at  the  l:)ottom,  filling-  the 
lowest  2  feet.      Another  well  of  the  same  description,  but  137  feet  deep. 


360  THE  GLACIAL  LAKE  AGASSIZ. 

is  a  mile  farther  east,  at  Wellington  Stewart's  house,  in  the  southwest  quarter 
of  section  4,  1,192  feet  above  the  sea. 

On  the  road  from  Olga  to  Walhalla  the  crest  of  the  east  margin  of  this 
delta  is  crossed  in  the  north  part  of  section  33,  Walhalla,  about  2  miles 
southeast  from  the  village  of  this  name.  Its  elevation  is  1,190  to  1,196 
feet  above  the  sea.  This  is  a  beach  accumulation,  belonging  to  the  third 
Herman  stage.  Toward  the  west  and  southwest  the  undulating  delta 
plateau,  mostly  covered  with  bushes  and  occasional  trees,  is  10  to  30  feet 
lower  for  a  width  of  1  to  1^  miles,  averaging  about  1,175  feet.  Northeast 
from  the  crest  of  this  road  a  short  descent  is  made  to  a  praiiie  terrace,  30 
to  60  rods  wide,  varying  in  elevation  from  1,182  to  1,169  feet,  but  mainly 
within  2  feet  above  or  below  1,175  feet.  In  general  the  verge  of  this 
terrace  is  its  lowest  portion.  Thence  a  very  steep  descent  of  169  feet  is 
made  on  the  road  from  1,173  to  1,004  feet,  this  being  the  very  conspicuous 
wooded  escarpment  called  the  "first  Pembina  Mountain."  It  is  the  eroded 
front  of  the  great  Pembina  delta,  the  eastern  part  of  which,  originally 
descending  more  moderately,  has  been  swept  away  by  the  waves  and  shore 
currents  of  the  lake  during  its  Norcross,  Tintah,  Campbell,  and  McCauley- 
ville  stages.  From  this  section  33  the  "first  mountain"  extends  southeast 
ta  sections  13  and  24,  township  162,  range  56,  and  northwest  across  the 
Pembina,  passing  close  southwest  of  Walhalla  and  onward  to  sections  10 
and  3,  township  163,  range  57.  Its  highest  part  is  intersected  by  the  Pem- 
bina River,  above  which  it  rises  on  each  side  in  bluffs  of  gravel  and  sand 
200  to  250  feet  high,  with  their  crest  a  half  mile  to  1  mile  apart.  From 
this  upper  portion  the  delta  slopes  down  gradually  toward  the  southeast 
and  toward  the  northeast  and  north,  extending  only  2  to  4  miles  north  of 
the  Pembina.^ 

'  The  first  Pembina  Mountain  was  visited  liy  D.  D.  Owen  in  1848.  He  describes  it  as  follows : 
"Pembin.a  Moimtain  is,  in  fact,  no  mountain  at  all,  nor  yet  a  hill.  It  is  a  terrace  of  table-land,  the 
ancient  shore  of  a  great  body  of  water  that  once  filled  the  whole  of  the  Eed  River  Valley.  On  its 
summit  it  is  quite  level  and  extends  so  for  about  5  miles  westward  to  another  terrace,  the  summit  of 
which,  I  was  told,  is  level  with  the  gre.at  buffalo  plains  that  stretch  away  towards  the  Missouri,  the 
hunting  grounds  of  the  Sioux  and  the  half-breed  jiopulatiou  of  Red  River." — Report  of  a  Geological 
Survey  of  Wisconsin,  Iowa,  and  Minnesot.a,  1852,  p.  178. 

Both  the  first  and  second  Pembina  mountains  were  examined  in  1857  by  Palliser,  who  says  of  the 
flat  Red  River  Valley  and  the  Pembina  delta :  "  This  plain,  no  doTibt,  had  formed  at  one  time  the  bed 
of  a  sheet  of  water,  and  the  Pembina  Hill,  consisting  of  previously  deposited  materi.als,  was  its 
western  shore." — Journals,  detailed  reports,  etc.,  presented  to  Parrliament,  19th  May,  1863,  p.  41. 


THE  PEMBINA  DELTA.  361 

Surface  at  the  Bellevvie  Hotel,  Walhalla,  994  feet  above  the  sea;  at 
the  post-office,  Mr.  G.  D.  Lormg-'s  store,  9G8  feet;  Pembina  River  at  the 
bridge,  a  third  of  a  mile  east  of  Walhalla,  low  and  high  water,  934  to 
943  feet. 

Highest  part  of  the  Pembina  delta  north  of  the  Pembina  River  in 
sections  25  and  26,  township  163,  range  57,  1,210  to  1,230  feet,  rising 
slowly  from  east  to  west;  in  the  west  half  of  section  26  and  the  east  edge 
of  section  27  it  is  depressed  to  1,225  and  1,220  feet;  but  beyond  this  it 
rises  to  1,235  and  1,240  feet,  next  to  the  foot  of  the  "second  mountain." 

Natural  surface  at  the  quarter-section  stake  on  the  north  side  of  sec- 
tion 26,  township  163,  range  57,  1,191  feet.  Third  Herman  beach,  crest 
5  rods  south  of  this  stake,  1,197  feet,  from  which  there  is  a  descent  in  5 
rods  south  to  1,192  feet  and  in  15  -rods  north  to  1,180  feet.  This  beach 
curves  thence  to  the  northwest  and  north,  and  in  the  opposite  direction 
runs  east-southeast  2  miles  to  near  the  center  of  section  30,  Walhalla, 
where  its  elevation  is  approximately  1,192  feet.  Other  shore-lines  of  the 
Herman  group  were  not  noticed  north  of  the  Pembina  River. 

In  the  gravel  of  this  delta,  as  seen  in  the  bluffs  of  the  Pembina  near 
Walhalla  and  at  noteworthy  springs  2  miles  to  the  south,  on  the  south  side 
of  the  river,  in  the  southwest  corner  of  section  32,  the  pebbles  of  some  beds 
are  mainly  Cretaceous  shale,  of  others  mostly  limestone,  and  of  others 
granite,  gneiss,  and  dark  trappean  rocks.  In  the  aggregate  these  three 
classes  have  a  nearly  equal  representation,  and  they  are  more  commonly 
intermingled  in  the  same  beds.  The  shale  was  doubtless  chiefly  derived 
from  the  erosion  of  its  strata  along  the  glacial  watercourse  from  the  Lake 
Souris,  and  was  occasionally  deposited  in  layers  almost  unmixed  with 
drift  materials;  but  the  other  constituents  of  the  gravel  were  derived  from 
the  overlying  drift  and  from  the  melting  ice-sheet.  White  quartz  and 
moss  agate  are  frequent,  and  bits  of  silicified  wood  occur  rarely;  but  no 
banded  agates  were  found.  Numerous  pieces  of  lignite,  rounded  by  water- 
wearing,  from  2  to  4  inches  in  diameter,  noticed  in  this  delta  gravel  at  the 
springs,  have  caused  some  to  look  for  workable  beds  of  this  kind  of  coal 
in  the  vicinity;  but  the  proportion  of  these  fi-agments  is  no  greater  than  in 
the  glacial  drift  generally  throughout  this  region  and  for  hundi'eds  of  miles 
to  the  south. 


362  THE  GLACIAL  LAKE  AGASSIZ. 

The  deposition  of  tliis  delta  took  place  during  the  highest  Herman 
stage  of  Lake  Agassiz  It  seems  to  have  been  very  rapid,  the  supply  of 
sediments  being  so  great  that  about  the  mouth  of  the  Pembina  Valley  they 
were  accumulated  in  a  fan-like  sloping  mass  to  a  height  of  more  than  50 
feet  above  the  lake  level.  When  the  recession  of  the  ice-sheet  caused  the 
cessation  of  its  supply  of  modified  drift,  and  permitted  the  Souris  to  flow,  as 
now,  to  the  Assiniboine,  the  gi'owth  of  this  delta  ceased;  and  its  subsequent 
history  is  that  of  the  deep  channels  cut  through  it  by  the  Little  Pembina 
and  the  Pembina,  and  of  the  steep  escarpment  sculptured  on  its  east  side. 
From  the  erosion  of  this  first  Pembina  Mountain  large  amounts  of  gravel 
and  sand  were  swept  southward,  notably  during  the  Campbell  stages  of  the 
lake,  when  they  were  deposited  in  a  very  massive  curving  beach  ridge  that 
crosses  the  Tongue  River  in  the  west  part  of  township  161,  range  55,  about 
7  miles  west  of  Cavalier.  In  the  Herman  stage,  while  the  delta  was  being 
accumulated,  much  fine  clay  and  silt,  brought  by  the  same  glacial  river, 
were  carried  farther  and  spread  upon  the  lake  bed  along  the  central  part 
of  the  Red  River  Valley,  perhaps  extending  in  appreciable  amount  nearly 
100  miles  southward  to  the  belt  of  till  that  reaches  across  the  valley  at 
Caledonia  and  forms  the  Goose  Rapids.  But  on  the  west  side  of  the 
lacustrine  area  this  fine  sediment  is  absent,  probably  because  of  currents 
trending  off"shore;  and  the  surface  is  till  both  soiith  and  north  of  the 
gravel  and  sand  delta,  as  from  Park  River  north  to  Gardar  and  Mountain 
and  nearly  to  the  Tongue  River,  and  from  2  miles  north  of  the  Pembina  to 
the  international  boundary  and  onward. 

During  the  Glacial  period  the  great  valley  of  the  Pembina  River  west 
of  its  delta  was  only  partially  filled  with  drift,  for  its  reexcavation,  with  the 
channeling  of  Langs  Valley,  tributary  to  it  from  the  glacial  Lake  Souris, 
would  have  supplied  as  large  a  tribute  to  Lake  Agassiz  as  the  entire  Pem- 
bina delta  and  the  fine  silt  and  clay  that  are  spread  over  the  adjacent  laka 
bed.  The  volume  of  the  delta,  as  before  stated,  is  ajjproximatelj^  2J  cubic 
miles.  If  an  equal  amount  of  fine  silt  were  deposited  beyond  the  delta, 
both  together  would  measure  about  the  same  as  Langs  Valley  and  the  Pem- 
bina Valley  from  the  former  mouth  of  Lake  Souris  to  the  delta,  namely, 
between  4  and  5  cubic  miles.'     But  much  of  the  Pembina  delta  and  lacus- 

'  See  pages  267-272,  foregoing. 


THE  PEMBINA  DELTA.  363 

trine  silt  was  doubtless  supplied  from  the  melting  ice-sheet  at  the  same  time 
with  the  deposition  of  the  tracts  of  modified  drift  that  border  the  valley 
north  of  Rock  and  Swan  lakes;  so  that  the  material  derived  from  erosion 
in  this  valley  was  considerably  less  than  would  be  required  to  fill  it.  More- 
over, it  seems  likely  that  the  entire  erosion  of  Langs  Valley — that  is,  of  the 
portion  of  this  watercourse  extending  from  the  Souris  to  Pelican  Lake — 
together  with  most  of  the  valley  along  the  extent  of  that  lake,  was  effected 
by  the  outflow  from  the  Lake  Souris  during  the  time  of  formation  of  the 
Pembina  delta;  and  tliis  large  supply  from  erosion  in  tiie  upper  part  of 
the  valley  still  further  diminishes  its  probable  amount  along  the  course 
of  the  river  below.  Thus  it  is  clearly  indicated  that  the  Pembina  Valley, 
like  the  valleys  of  the  Minnesota,  Sheyenne,  and  Assiniboine  rivers,  was 
eroded  during  preglacial  time  and  was  not  entirely  filled  by  the  drift. 
Comparing  this  delta  with  all  the  other  conspicuous  deltas  of  Lake  Agassiz, 
it  seems  indeed  probable  that  more  than  half  of  its  mass  was  supplied 
directly  from  the  englacial  drift  of  the  ice-sheet,  and  that  less  than  half 
came  from  erosion  of  the  valley,  which,  therefore,  along  the  lower  and 
deeper  portion  of  its  course  appears  not  to  have  been  much  obstructed  by 
the  glacial  drift.  From  this  it  follows  that  the  extensive  high  terraces 
observed  on  the  sides  of  the  Pembina  Valley  in  the  vicinity  of  the  Mow- 
bray bridg-e  and  westward  (page  270)  are  due  to  preglacial  erosion  in  the 
Cretaceous  shales,  owing  to  the  action  of  the  ice-sheet  only  their  minor 
features,  together  with  the  di-ift  forming  their  surface. 

THE  UPPKR    OR    HERMAN    BEACHES  AKD    DELTAS    IN    MANITOBA. 

FROM    THE    INTERNATIONAL    BOUNDARY    TO    THE    VICINITY    OP    NEEPAWA. 

(PLATES   XXX,    XXXI,    AND   XXXII.) 

The  west  shore  of  Lake  Agassiz  enters  Manitoba  2  miles  west  of  the 
east  line  of  range  5,  at  a  distance  of  36  miles  from  the  Red  River.  On 
the  international  boundary  and  for  the  next  10  miles  northward  the  shores 
of  the  highest  stages  of  tlie  lake  wei'e  on  the  steep  wooded  escarpment  of 
the  Pembina  Mountain,  the  base  of  which  here  is  1,100  to  1,150  feet 
above  the  sea,  rising  slightly  northward,  and  the  verge  of  its  top,  1,300  to 


364  THE  GLACIAL  LAKE  AGASSIZ. 

1,400  feet.     This  ascent,  forming  the  steep  face  of  the  Pembina  Mountain, 
is  made  upon  a  width  of  about  a  quarter  of  a  mile. 

^Vliere  the  Pembina  Mountain  plateau  is  ascended  by  the  Southwestern 
Branch  of  the  Canadian  Paciiic  Railway,  and  for  a  distance  of  about  4 
miles  south  and  2  miles  noi'th  of  this  railway,  the  principal  line  of  escarp- 
ment is  replaced  by  a  moderate  slope  which  is  chiefly  prairie.  Across  this 
tract  the  Herman  beaches  of  Lake  Agassiz  are  well  developed.  In  order 
proceeding  northward,  the  first  point  of  examination  of  the  highest  beach 
was  near  William  H  Oakley's  house,  in  the  south  edge  of  the  southwest 
quarter  of  section  26,  towns'hip  2,  range  6.  It  is  here  a  massive  rounded 
ridffe  of  g-ravel  and  sand,  with  descent  of  12  to  15  feet  in  a  distance  of  as 
many  rods  both  to  the  east  and  west  from  its  crest,  which  is  1,253  feet 
above  the  sea.  Northward  this  beach,  with  similar  outline,  extends  to 
Francis  J.  Parker's  house,  which  is  built  on  its  crest,  having  there  also  a 
height  of  1,253  feet,  in  the  north  edge  of  the  northwest  quarter  of  this 
section.  Westward  from  this  beach  is  an  undulating  surface  of  till  with 
few  bowlders.  Half  a  mile  farther  north  the  beach  is  intersected  by  the 
deep  and  broad  ravine  of  Dead  Horse  or  Cheval  Creek.  Beyond  this 
ravine  the  beach  begins  near  Samuel  B.  Bowen's  house.  Its  elevation  1  to 
IJ  miles  north-northwest  of  Mr.  Bowen's  is  1,255  to  1,259  feet,  and  it  is 
there  spread  more  broadlv  than  usual,  having  a  nearly  flat  surface  on  a 
width  of  20  to  30  rods,  bordered  on  the  east  by  a  descent  of  10  or  15  feet 
in  20  I'ods,  and  on  the  west  by  a  descent  of  about  4  feet.  The  beach  is 
gravel  and  sand,  with  till  on  each  side.  It  has  nearly  the  same  features 
also  a  tliird  of  a  mile  farther  north,  near  the  center  of  section  10,  township 
3,  ]-a.nge  6,  where  it  is  crossed  by  the  road  from  ]\Iorden  to  Thornhill,  the 
elevation  of  its  crest  being  1,258  feet,  l)ut  the  depression  on  the  west  is 
reduced  to  onlj'  1  or  2  feet.  In  the  same  section  this  and  lower  beach 
ridges  are  excavated  beside  the  railway  for  ballast,  and  are  found  to  consist 
of  sand  and  gravel,  with  pebbles  seldom  exceeding  2  or  3  inches  in  diame- 
ter. About  half  of  the  pebbles  are  light-gray  magnesian  limestone  and 
about  half  Cretaceous  shale,  such  as  forms  the  Pembina  Mountain,  with 
only  a  small  proportion  derived  from  Archean  rocks.  Thence  the  highest 
shore  continues  north  tlu'ough  the  east  part  of  sections  16  and  21,  township 


U.S. GEOLOGICAL  SURVEY 


MONOGRAPH    XXV.    PL. XXXI 


MAP  OF  THE  WESTERN  SHORES  OF  LAKE   AGASSIZ   IX  MANITOBA.  FROM  MORDEN 
AND  THORNHILL  NORTH    TO  THE  ASSINIIiOINE  RIVER. 

Scale,  ()  miles  to  an  iiicli. 


Lake  Area 


He'll  a 


ANj.Ut.tJfs    fi/'   lietnway   s/ations    ciie     in>!i'd     in    fcef.     <ih<>\('    (he    Roo.  . 


HERMAN  BEACHES  IN  MANITOBA.  365 

3,  range  6,  and  in  section  28  comes  to  the  steep  escarpment  of  Pembina 
Mountain,  with  which  it  coincides  along  the  next  30  miles  north-northwest. 
The  elevation  of  this  beach  shows  that  it  is  the  continuation  of  the  highest 
in  the  series  of  Herman  beaches  in  Minnesota  and  North  Dakota. 

About  a  quarter  of  a  mile  east  of  tin  foregoing  is  a  parallel  beach  15 
to  20  feet  lower,  the  second  in  the  Herman  series.  Newton  Lane's  house, 
next  east  of  Mr.  Oakley's,  is  built  on  its  crest,  1,237  feet  above  the  sea.  It 
there  has  a  descent  of  15  feet  or  morf  within  an  eighth  of  a  mile  to  the 
east;  but  on  the  west  the  descent  is  only  1  or  2  feet  or  in  part  wanting,  and 
a  nearly  level  surface  of  sand  and  gravel  reaches  west  to  the  upper  beach. 
In  section  10,  township  3,  range  6,  at  the  road  from  Morden  to  Thornhill, 
this  second  Herman  beach  has  a  height  of  1,241  feet,  and  another  beach  at 
1,247  feet  lies  between  this  and  the  highest,  indicating  similar  conditions 
in  the  fall  of  the  lake  level  as  on  the  northwest  side  of  Maple  Lake,  in 
Minnesota,  where  such  an  intervening  beach  also  occurs. 

Three  small  parallel  beach  ridges  referable  to  the  third  stage  in  the 
Herman  series  are  crossed  in  the  west  pail  of  section  24,  township  2,  range 
6,  by  the  road  leading  northwest  from  Mountain  City.  The  elevation  of 
their  crests  is  1,198,  1,202,  and  1,205  feet.  Two  miles  farther  north,  near 
the  center  of  section  35,  in  the  same  township,  William  Miller's  house  is 
built  on  the  highest  of  these,  at  an  elevation  of  about  1,210  feet.  His  well, 
16  feet  deep,  is  gravel  and  sand  to  the  depth  of  12  feet,  with  till  below. 
Northward  these  beaches  are  traceable  tlu-ough  sections  2,  11,  15,  and  the 
south  part  of  section  22,  township  3,  range  6,  to  Bradshaws  Creek,  beyond 
which  they  pass,  with  the  other  Herman  and  Norcross  beaches,  along  the 
Pembina  Mountain  escarpment. 

The  fourth  Herman  beach  passes  through  Mountain  City,  in  section 
24,  township  2,  range  6,  the  post-office  and  the  south  end  of  the  principal 
street  being  on  its  crest,  at  1,191  to  1,192  feet.  Twenty -five  rods  farther 
east,  at  the  schoolhouse,  is  a  less  conspicuous  parallel  beach,  at  1,183  to 
1,184  feet.  Both  are  terrace-like  in  form,  having  a  descent  of  3  to  5  feet 
or  more  on  the  east,  but  only  1  to  2  feet  or  none  on  the  west.  The  contin- 
uation of  this  shore  was  also  observed,  like  the  preceding,  through  a 
distance  of  6  miles  northward. 


366  THE  GLACIAL  LAKE  AGASSIZ. 

From  section  28,  township  3,  range  6,  the  Herman  shores  of  Lake 
Agassiz  coincide  with  the  prominent  escarpment  of  the  Pembina  Moun- 
tain through  a  distance  of  29  miles,  passing  in  a  nearly  straight  course 
north-northwesterly  to  section  30,  township  7,  range  8,  about  7  miles  east- 
southeast  from  Treherne.  Along  this  distance  the  base  of  the  escarpment 
is  1,100  to  1,125  feet  above  the  sea,  and  its  crest  about  1,400  feet.  Seen 
from  this  elevation,  the  great  plain  of  the  Red  River  Valley  on  the  east, 
when  overshading  clouds  give  to  it  in  the  distance  a  dark  blue  or  azure 
color,  appears  not  unlike  the  vast  expanse  of  the  ocean  as  viewed  from  an 
equal  height  a  few  miles  inland.  The  highest  shore  of  the  glacial  lake  was 
about  half  way  up  this  ascent,  and  the  lower  Herman  beaches  and  those  of 
the  Norcross  stage  were  between  this  and  the  base. 

At  the  north  end  of  the  Pembina  Mountain  the  Herman  shores  of 
Lake  Agassiz  turned  from  a  northward  to  a  westward  course,  and  at  the 
sharpest  portion  of  this  bend,  in  section  36,  township  7,  range  9,  the  cur- 
rents along  the  shore,  caused  by  storms,  brought  a  large  amount  of  gravel 
and  sand  from  their  erosion  on  each  side,  and  accumulated  these  deposits 
in  a  massive  ridge  which  juts  out  north-northwesterly  a  mile  or  more 
from  the  curving  line  of  the  escai-jDment.  This  gravel  and  sand  spit  sinks 
from  nearly  1,300  feet  above  the  sea  at  its  south  end,  where  it  rests  on 
the  adjoining  highland,  to  about  1,125  feet,  comprising  deposits  of  the 
successive  Herman,  Norcross,  and  Tintah  stages  of  the  lake. 

Five  to  6  miles  farther  west  the  Herman  beaches  are  well  exhibited  in 
the  gradual  ascent  that  rises  to  the  Tiger  Hills,  1  mile  south  of  Treherne. 
The  highest  beach  here  crosses  the  middle  of  the  northwest  quarter  of 
section  31,  township  7,  range  9,  where  it  forms  a  swell  of  sand  and  gravel, 
with  pebbles  mostly  of  Cretaceous  shale,  having  its  crest  1,272  to  1,273 
feet  above  the  sea.  In  some  portions  this  reaches  nearly  flat  an  eighth  of 
a  mile  south  to  the  base  of  the  Tiger  Hills,  but  elsewhere  it  is  divided  from 
them  by  a  depression  of  3  to  5  feet.  This  appears  to  be  the  second  (b)  in 
the  series  of  Herman  beaches,  the  first  of  this  series  (a  and  ad)  not  being 
found  here  nor  farther  north.  At  the  time  when  that  uppermost  beach  of 
Lake  Agassiz  was  formed  this  locality  and  the  country  northward  are 
beheved  to  have  been  covered  by  the  ice-sheet,  its  termination  being  at  the 


HEEMAN  BEACHES  NEAR  TEEHERNB.  367 

tract  of  morainic  di'ift  which  overspreads  the  east  part  of  the  Tiger  Hills, 
as  crossed  in  township  7,  range  9,  by  the  road  to  the  south  from  Treherne. 
About  20  and  50  rods  north  of  the  beach  just  described  two  inconspicuous 
beach  lines,  terrace-like  sand  and  gi-avel  deposits,  are  found  at  1,266  and 
1,254  feet,  referable  to  subdivisions  [h^  and  hb)  of  the  second  Herman 
stage.  A  little  farther  north  the  third  Herman  beach  is  represented  at 
Irvine  Scarrow's  house,  in  the  south  edge  of  section  6,  township  8,  range  9. 
This  is  a  slight  terrace  with  crest  at  1,243  and  1,244  feet  and  descent  of 
4  or  5  feet  on  its  north  side.  Mr.  Scarrow's  well,  on  this  beach,  31  feet 
deep,  consists  of  black  soil,  2  feet;  interbedded  sand  and  clay,  10  feet; 
very  coarse  shale  gravel,  5  feet ;  beds  of  coarse  and  fine  gravel  and  sand, 
13  feet;  and  very  hard  dark  bluish  till  at  the  bottom,  dug  into  only  1  foot. 
This  well  shows  an  accumulation  of  shore  drift  to  a  depth  of  30  feet, 
swept  out  by  the  currents  of  the  lake  from  the  curve  where  its  beaches 
turned  westward.  About  an  eighth  of  a  mile  north  of  Mr.  Scarrow's  house 
another  beach,  also  referable  to  the  third  Herman  stage,  descends  from 
1,236  and  1,238  feet  at  its  crest  to  1,230  feet  at  the  base  of  its  northward 
slope.  At  the  summit  of  the  Manitoba  and  Southwestern  Kailway,  a  mile 
east  of  the  Little  Boyne  River,  and  on  the  slope  thence  eastward,  very 
massive  beach  deposits  are  accumulated,  due  apparently  to  the  same 
action  of  northwestward  ciu-rents  from  the  northern  end  of  the  Pembina 
Mountain.  The  summit  of  the  railway  is  on  such  a  beach,  1,217  to  1,220 
feet  above  the  sea,  the  fourth  in  the  Herman  series,  forming  a  broad  swell 
from  which  a  gentle  slope  falls  on  its  northeast  and  southwest  sides.  Arthur 
Willett's  well  here  goes  to  a  depth  of  42  feet  in  beds  of  sand  and  gravel, 
obtaining  a  plentiful  supply  of  good  water  from  their  lower  portion,  with- 
out reaching  their  bottom.  A  fifth  of  a  mile  farther  east  the  railway  cuts  a 
beach  ridge  with  its  crest  at  1,211  feet,  also  referable  to  the  fourth  Herman 
stage. 

The  Assiniboine  delta  occupies  the  western  border  of  Lake  Agassiz 
from  Treherne  westward  about  60  miles  to  Brandon,  and  thence  north- 
eastward about  35  miles  to  Neepawa.  The  shore  of  the  lake  along  these 
distances  is  not  generally  marked  by  a  definite  beach  ridge,  the  absence  of 
which  seems  to  be  accounted  for  chiefly  by  the  extreme  shallowness  of  the 


368  THE  GLACIAL  LAKE  AGASSIZ. 

lake  upou  the  delta,  so  tliat  powerful  waves  were  not  di-iven  ashore  by 
storms.  The  course  of  the  highest  shore  between  Treheme  and  Brandon, 
belonging  to  the  time  of  the  second  Herman  beach,  passes  first  west- 
southwest  along  the  foot  of  the  Tiger  Hills  to  the  north  and  west  side  of 
Campbell's  Hill,  in  section  4,  township  7,  range  12 ;  thence  southwest  and 
south  to  the  Cypress  River,  near  Grange  post-office,  in  section  18,  town- 
ship 6,  range  12;  thence  west-northwestward  to  Oak  Creek  and  along  the 
south  side  of  this  creek,  within  a  mile  or  less  from  it,  nearly  to  its  mouth; 
and,  crossing  the  Souris  in  section  31,  township  7,  range  16,  passes  thence 
northwest  to  Brandon.  Beyond  the  Cypress  a  belt  of  till,  moderately  undu- 
lating or  in  part  nearly  flat,  from  2  or  3  to  10  miles  wide,  separates  this 
lake  shore  from  the  northern  border  of  the  Tiger  Hills  and  the  eastern 
and  northern  base  of  the  Brandon  Hills.  S.  Martin's  house,  in  the  north- 
east quarter  of  section  28,  township  8,  range  17,  about  15  miles  southeast 
of  Brandon,  is  built  on  a  small  beach  ridge  of  sand  and  gravel  extending 
from  southeast  to  northwest,  only  slightly  below  the  highest  stage  of  the 
lake,  which  is  marked  by  a  moderately  sloping  parallel  escarpment,  about 
10  feet  high,  eroded  in  till  a  half  mile  southwest  of  this  beach.  The 
unusually  smoothed  surface  of  the  till  extending  thence  west  and  south 
to  the  Brandon  and  Tiger  Hills,  on  the  area  crossed  by  the  Souris  in  its 
course  from  Gregory's  mill  to  the  mouth  of  Black  Creek,  is  probably 
attributable  to  the  deposition  of  its  upper  portion  in  a  body  of  water  held 
between  these  hills  and  the  northwardly  retreating  ice-sheet  before  this 
area  was  drained  to  the  level  of  Lake  Agassiz  by  the  retreat  of  the  ice 
from  the  east  part  of  the  Tiger  Hills  and  the  north  end  of  the  Pembina 
Mountain. 

In  the  south  part  of  the  city  of  Brandon  the  second  Herman  beach, 
marking  the  stage  bb  of  the  table  in  Chapter  IX,  is  a  well-defined  ridge  of 
sand  and  gi-avel  along  a  distance  of  about  a  mile.  It  extends  from  east  to 
west,  passing  an  eighth  of  a  mile  north  of  the  court-house,  and  thence  close 
along  the  south  side  of  Lome  avenue  from  First  to  Fourth  street.  Between 
Fourth  and  Sixth  streets  it  is  crossed  by  this  avenue,  and  thence  westward 
lies  close  on  its  north  side.  Its  structure  is  shown  by  sections  where  it  is 
intersected  by  Tenth,  Eleventh,  and  Twelfth  streets,  exposing  a  thickness 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL. XXXII. 


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^^  ^-                                                                                                                                                                                                                                                                                                                                                        JULIUS  BIEN   6  CO   NV 

MAI'   OF  THE   n'ESTERN  SHORES  OF  LAKE  AGASSIZ    IN  THE  \'l(TXrrY  OK    llll': 
CANADIAN  PAC'TFIC  HAILA\"AV  AND  NORTH   TO  OHANGK  UIDGE,  MAXri'OI'.A. 

Scale,  6  miles  to  .an  inch. 


Lake  Ai-ea 


Delia    777] 


AUiUule.s  of  H,GJX\vciv  stations  ewe   n-oted-   in,   fl-ei    nhove   tJic   sea. 


HERMAN  BEACHES  IN  BRANDON.  369 

of  10  feet  of  obliquely  bedded  sand  and  gravel,  cOutaining  abundant  peb- 
bles up  to  2  inches  and  rarely  cobbles  3  or  4  inches  in  diameter,  about 
two-tliirds  being  Paleozoic  magnesian  limestones,  from  one-tenth  to  one- 
fourth  Cretaceous  shale,  and  the  remainder  mostly  Archean  granites  and 
schists.  This  beach  ridge  varies  from  10  to  20  rods  in  width  and  from  5 
to  10  feet  or  more  in  height,  having  a  smoothly  rounded,  wave-like  form. 
The  elevation  of  its  crest  near  th^  court-house  ranges  from  1,260  to  1,269 
feet  above  the  sea,  and  at  Eleventh  and  Twelfth  streets  it  is  1,260  to 
1,261  feet.  No  distinct  beach  ridge  of  the  slightly  higher  Herman  h  stage 
of  Lake  Agassiz  was  found  in  the  vicinity  of  Brandon,  but  evidence  of  the 
lake  level  in  that  stage  is  afforded  in  the  southeast  part  of  Brandon  by 
the  delta  plateau  of  coarse  gravel  and  sand  at  the  court-house  and  east- 
ward, wliich  is  1,270  to  1,282  feet  above  the  sea,  and  by  an  old  water- 
course crossed  3  to  4  miles  west  of  Brandon  on  the  road  to  Kemnay,  both 
of  which  are  more  fully  noticed  in  the  description  of  the  Assiniboine  delta. 
North  of  the  Assiniboine  the  highest  shore  of  Lake  Agassiz  passes 
from  Brandon  east  and  east-northeast  by  Chater  and  Douglas,  being  on  or 
close  below  the  verge  of  the  plateau  of  till,  overspread  by  delta  gravel  and 
sand,  which  lies  close  north  of  the  Canadian  Pacific  Railway.  About  a 
mile  north  of  Douglas  station  this  shore  is  marked  by  a  dune  hillock,  neax-ly 
at  the  middle  of  the  line  oetween  sections  10  and  11,  township  11,  range  17. 
Thence  its  course  is  north-northeastward,  and  is  indicated  by  an  eroded 
escarpment,  extending  2  or  3  miles,  with  a  height  of  10  to  15  feet,  and  less 
distinctly  observable  a  few  miles  beyond.  The  base  of  this  escarpment 
where  it  crosses  the  south  line  of  section  24  in  this  township  is  1,269  feet 
above  the  sea;  and  the  surface  at  the  schoolhouse,  a  sixth  of  a  mile  farther 
west,  is  about  20  feet  higher.  All  the  area  eastward  is  delta  sand  and 
gravel;  but  the  escarpment  and  the  country  rising  thence  slowly  north- 
westward are  till.  The  continuation  of  this  line  between  a  moderately 
rolling  sm-face  of  till  on  the  west,  with  plentiful  bowlders  and  frequent 
lakelets,  and  the  slightly  undulating  sand  and  gravel  delta  on  the  east,  with 
low  dunes  on  many  parts  of  its  area,  passes  north-northeasterly  in  range  16 
across  the  west  half  of  township  12  and  the  east  half  of  township  13,  and 
thence  north  thi-ough  the  eastmost  tier  of  sections  in  township  14,  to  Stony 
MON  XXV 24 


370  THE  GLACIAL  LAKE  AGASSIZ. 

Creek.  It  evidently  marks,  at  least  approximately,  the  higliest  shore  of 
the  glacial  lake;  but  it  bears  uo  distinct  beach  ridge  nor  line  of  erosion, 
partly  because  the  lake  was  so  shallow  on  the  adjoining  delta  area,  and  partly 
because  the  prevailing  trends  of  the  inequalities  in  the  till  surface  run 
nearly  from  east  to  west,  transverse  to  the  course  of  the  shore  currents  and 
di'ift  by  which  beaches  would  be  formed,  thus  intercepting  the  scanty 
deposits  of  beach  gravel  and  sand  in  their  hollows,  instead  of  permitting 
them  to  be  accumulated  in  a  distinct  ridge. 

The  Manitoba  and  Northwestern  Railway  crosses  two  beach  ridges  at 
3f  miles  and  3  miles  west  of  Neepawa,  the  crests  of  which  are  respectively 
1,323  and  1,304  feet  above  the  sea.  These  elevations  indicate  that  they 
belong  to  subdivisions  of  the  second  Herman  stage,  in  the  same  manner 
that  this  stage  is  represented  by  thi-ee  beach  lines  at  Treherne.  Each  of 
thes'e  ridges  has  a  height  of  about  7  feet  above  the  adjoining  surface  and 
a  width  of  30  to  40  rods.  They  consist  of  sand  and  gravel,  and  the  rail- 
way company  has  therefore  purchased  a  considerable  tract  occupied  by 
the  lower  one  of  them  for  its  excavation  and  use  as  railway  ballast.  This 
lower  beach  probably  marks  the  same  lake  level  as  the  beach  observed  at 
Brandon,  having  there  an  elevation  of  1,260  to  1,269  feet.  Gravel  and 
sand  brought  into  Lake  Agassiz  by  Stony  Creek  seem  to  have  contributed 
to  the  conspicuous  development  of  beach  deposits  here,  while  they  are 
wanting  or  less  distinct  upon  most  of  the  shore  southward  to  Brandon  and 
also  northward  through  the  next  12  miles  to  where  the  Herman  and  Nor- 
cross  shores  pass  into  the  steep  escarpment  that  forms  the  eastern  face  of 
Riding  Mountain. 

DELTA    OF   THE   ASSINIBOINE    RIVEK. 

(plate   XXXIII.) 

At  Brandon  the  Assiniboine  enters  the  area  of  Lake  Agassiz,  and  thence 
the  gravel  and  sand  delta  of  this  tributary  extends  eastward  75  miles  to 
Portage  la  Prairie,  northeastward  50  miles  to  Grladstone,  and  east-south- 
eastward 80  miles  to  Almasippi  post-office,  9  miles  west  of  Carman.  On 
the  northwest  this  delta  is  bordered  by  an  expanse  of  moderately  undu- 
lating or  rolling  till  which  rises  slowly  above  the  ancient  lake  level  and 


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THE  ASSINIBOINE  DELTA.  371 

stretches  northwestward  from  Brandon,  Chater,  and  Douglas  to  the  Little 
Saskatchewan  and  Oak  rivers.  From  Brandon  to  Douglas  the  boundary  of 
the  delta  is  close  north  of  the  Assiniboine  and  the  Canadian  Pacific  Rail- 
way; but  at  Douglas  the  line  dividing  the  delta  sand  and  gravel  and  the 
adjoining  surface  of  till  turns  north-northeastward  and  extends  about  20 
miles  in  a  nearly  direct  course  toward  Neepawa,  then  bends  northward  in 
the  east  part  of  townships  13  and  14,  range  16,  and  crosses  Stony  Creek 
a  few  miles  west  of  Neepawa.  Between  Brandon  and  the  mouth  of  the 
Souris  the  delta  reaches  3  or  4  miles  southwest  of  the  Assiniboine,  beina: 
there  also  bordered  by  a  smoothly  undulating  or  rolling  tract  of  till,  but 
the  morainic  Brandon  Hills  rise  prominently  within  a  few  miles  farther 
west.  From  the  Souris  east  to  the  Cypress,  a  distance  of  nearly  25  miles, 
the  southern  margin  of  the  delta  is  similarly  divided  from  the  Tiger  Hills 
by  a  belt  of  undulating  and  rolling  till  which  averages  about  5  miles  in 
width.  Farther  to  the  east  the  delta  deposits  abut  directly  upon  the  north- 
ern base  of  these  hills  from  the  Cypress  River,  by  Holland  and  Treherne, 
to  the  north  end  of  the  Pembina  Mountain.  Thence  to  the  southeast  the 
head  streams  of  the  Boyne,  after  their  descent  from  the  plateaxx  of  the  Pem- 
bina Mountain,  cross  the  southeastward  extension  of  this  delta  to  Almasippi. 
This  portion,  however,  is  not  probably  a  part  of  the  delta  as  it  was  at  first 
deposited,  but  has  been  derived  from  the  erosion  of  the  eastern  front  of  the 
original  delta  by  the  waves  of  the  lake  in  its  later  and  successively  lower 
stages,  being  transported  thence  southward  by  shore  cuiTents.  The  same 
lacustrine  action  has  doubtless  extended  the  delta  of  gravel  and  sand  gen- 
erally 5  to  15  miles  eastward  beyond  its  original  area,  thereby  giving  its 
eastern  face  a  more  gradual  slope.  As  thus  enlarged  its  east  boundary 
runs  north  from  Almasippi  to  Portage  la  Prairie,  curving  eastward  between 
these  places,  and  thence  it  passes  west-northwest  to  near  Gladstone,  Arden, 
and  Neepawa.  The  eastern  base  of  the  delta,  where  it  adjoins  the  flat 
expanse  of  the  Red  River  Valley  and  the  country  bordering  the  lower 
Assiniboine  and  Lake  Manitoba,  has  an  elevation  of  850  to  900  feet  above 
the  sea;  while  the  high  delta  plateau,  which  was  submerged  only  about  50 
feet  or  less  by  the  lake  when  it  was  being  deposited,  and  was  in  part  shoals 
and  low  islands,  has  an  elevation  of  from  1,200  to  1,275  feet  above  the  sea. 


372  THE  GLACIAL  LAKE  AGASSIZ. 

The  western  and  southern  hmits  of  the  plateau  are  those  akeady  noted, 
and  on  the  east  its  boundary  runs  north  and  northwest  from  Treherne  to 
Sydney  and  Neepawa.  The  area  of  the  plateau  is  about  1,300  square 
miles,  and  the  eastern  slope  adds  to  this  fully  two-thirds  as  much,  making 
the  total  area  of  this  delta  somewhat  more  than  2,000  square  miles. 

The  thickness  of  the  Assiniboine  delta  is  seldom  shown  by  wells, 
which  generally  obtain  a  plentiful  supply  of  water  upon  this  area  within 
moderate  depths,-  ranging  from  10  to  50  feet.  In  some  localities,  however, 
near  the  great  valley  that  the  Assiniboine  has  cut  tlirough  the  delta,  the 
plane  of  saturation  probably  lies  much  deeper,  and  wells  must  be  sunk  100 
feet  or  more  to  obtain  water.  Better  measures  of  the  depth  of  these  gravel 
and  sand  deposits  are  supplied  by  the  valleys  of  the  Assiniboine  and  other 
streams,  which  are  eroded  in  their  deeper  portions  100  to  200  feet  below 
the  top  of  the  delta  plateau  before  reaching  the  underlying  till.  Deep 
ravines  are  especially  numerous  on  the  northern  part  of  the  delta,  where 
many  springs  issue  near  the  plane  of  junction  between  the  porous  gravel 
and  sand  beds  and  the  till,  giving  rise  to  the  Squirrel,  Pine,  and  Silver 
creeks,  which  flow  northeast  to  the  White  Mud  Rivei".  The  descent  of  200 
to  300  feet  made  within  a  few  miles  upon  the  eastei'u  face  of  the  delta  is  a 
fui-ther  indication  of  its  thickness,  which  reaches  its  maximum  at  the  verge 
of  the  plateau.  In  the  vicinity  of  the  outcrop  of  Niobrara  beds  on  the 
Assiniboine,  in  section  36,  township  8,  range  11,  the  thickness  of  the  delta 
gravel  and  sand  appears  to  be  about  200  feet;  and  it  probably  ranges  from 
100  to  200  feet  along  the  outer  limit  of  the  plateau  through  the  greater 
part  of  its  extent  of  more  than  50  miles.  The  average  thickness  of  this 
very  extensive  delta  is  probably  between  50  and  75  feet.  Computing  its 
volume  for  an  average  of  50  feet  on  an  area  of  2,000  square  miles,  it  is 
found  to  be  about  20  cubic  miles. 

Fig.  16  presents  a  section  crossing  the  central  part  of  the  Assiniboine 
delta,  along  the  line  of  the  Canadian  Pacific  Railway  from  Brandon  to 
Portage  la  Prairie. 

Fifty  miles  east-southeast  from  Brandon  the  highest  portions  of  the 
surface  of  the  delta  south  of  the  Assiniboine  and  east  of  the  Cypress,  where 
it  has  not  been  heaped  in  sand  hills  by  the  wind,  ai-e  1,225  to  1,240  feet 


THE  ASSmiBOINE  DELTA. 


373 


above  the  sea,  the  latter  being  its  elevation  in  a  broad  swell  near  the  center 
of  section  24,  township  8,  range  11.  Ten  to  20  miles  thence  westward, 
between  Cypress  River  and  Glenboro,  the  elevation  of  the  slightlj^  undulat- 
ing surface  of  the  delta  is  mostly  1,235  to  1,245  feet,  with  frequent  sloughs 
and  permanent  ponds,  up  to  a  quarter  of  a  mile  or  more  in  extent,  lying  at 
1,225  to  1,235  feet.  These  ponds  abound  near  Glenboro  and  for  4  miles 
east.  Along  the  Canadian  Pacific  Railway  from  Sydney  westward,  by 
Melbourne,  Carberry,  and  Sewell,  to  Douglas,  20  to  25  miles  north  of  the 
foregoing,  the  undulating  delta  ranges  in  elevation  from  1,230  to  1,275 
feet;  and  it  holds  the  same  height  through  25  miles  northward,  to  within  3 
miles  southeast  of  Neepawa.  Adjoining  the  undulating  and  rolling  area  of 
till  which  borders  this  part  of  its  area  on  the  west,  its  expanse  of  gravel 


Fig.  16.— Section  across  the  delta  of  the  AssiDibnine  River.    Horizontal  scale.  15  niilo.^  to  an  inch. 

and  sand  slowly  rises  northward  from  1,265  and  1,270  feet  2  to  3  miles 
northeast  of  Douglas  to  1,275  and  1,280  feet  between  Willow  or  Boggy 
and  Spring  creeks.  These  elevations  represent  the  plateau  before  men- 
tioned, which  forms  the  greater  part  of  this  delta. 

While  the  extensive  area  of  this  plateau,  reaching  50  miles  from  east 
to  west  and  nearly  the  same  distance  from  north  to  south,  is  thus  so  uniform  ■ 
in  its  elevation  that  its  deposition  must  be  attributed  to  stages  of  the  lake 
when  its  level  was  not  much  higher,  probably  those  of  the  Herman  beaches 
b  and  hh  near  Treherne  and  Neepawa,  there  is  a  considerable  tract  lying 
on  both  sides  of  the  Assiniboine  in  the  vicinity  of  Brandon  and  Kemnay 
upon  which  delta  deposits  closely  associated  with  this  plateai;  ascend  from 
a  few  feet  to  125  feet  above  it  in  a  distance  of  12  or  15  miles  from  east  to 


374  THE  GLACIAL  LAKE  AGASSIZ. 

west.  A  mile  north  of  Brandon  the  bhiff  on  the  north  side  of  the  Assini- 
boine  rises  about  140  feet  above  the  river  to  1,300  feet,  approximately, 
above  the  sea.  It  consists  of  till  to  a  height  of  100  feet  or  more;  but  its 
crest  and  the  sm-face  thence  northward  for  5  miles  are  mostly  undulating 
gravel  and  sand  to  a  thickness  of  10  to  20  feet,  thinly  covering  the  till, 
which  forms  the  surface  farther  north.  Eastward  this  bluff,  eroded  by  the 
Assiniboine  since  the  deposition  of  this  stratified  gravel  and  sand,  extends 
along  the  nort,h  side  of  the  railway  by  Chater  and  Douglas,  having  a 
height  of  about  75  and  50  feet,  respectively,  at  these  stations,  but  declin- 
ing only  slightly  in  the  elevation  of  its  crest,  which  is  1,275  to  1,290  feet. 
Delta  gravel  and  sand,  and  on  some  portions  fine  silt,  cover  a  width  of  3 
or  4  miles  thence  northward  through  the  south  half  of  townships  11  of 
ranges  18  and  17,  having  an  elevation  at  their  northern  limit  1,300  to 
1,290  feet  above  the  sea,  beyond  which  the  surface,  gradually  ascending 
northward,  is  till.  The  most  eastern  point  of  this  higher  delta  deposit  is  in 
section  14,  township  11,  range  17.  Measured  thence  to  its  western  limit 
on  the  north  side  of  the  Assiniboine,  half  way  between  Kemnay  and 
Alexander,  its  length  is  24  miles.  Its  width  north  and  south  of  Brandon  is 
about  12  miles.  Through  it  the  Assiniboine  has  eroded  its  valley,  and  has 
carried  it  away,  cutting  also  into  the  underlying  till,  upon  a  large  area 
from  Brandon  east  to  Chater  and  Douglas  and  thence  south  nearly  to  the 
Brandon  Hills. 

South  of  the  river,  at  the  court-house,  in  the  southeast  part  of  Brandon, 
very  coarse  gravel  and  sand  of  this  higher  part,  of  the  Assiniboine  delta, 
containing  waterworn  cobbles  up  to  6  and  8  inches  in  diameter,  form  a  pla- 
teau mostly  1,270  to  1,275  feet  above  the  sea,  but  rising  to  1,282  feet  at  a 
distance  of  1  mile  to  the  east.  One  and  a  half  to  3  miles  west  of  Brandon 
a  similar  plateau  varies  in  height  from  1,290  to  1,305  feet.  Between  these 
small  plateaus  or  plains,  which  slope  about  5  feet  per  mile  to  the  east  and 
were  once  continuous,  a  former  watercourse,  diminishing  from  a  half  to  a 
quarter  of  a  mile  in  width,  passes  southeast  from  the  valley  of  the  Assini- 
boine through  the  south  part  of  Brandon  and  thence  continues  east  nearly 
3  miles,  opening  in  section  7  or  8,  township  10,  range  18,  upon  the  broad 
lower  area  eroded  by  the  Assiniboine.     The  bed  of  this  old  channel  is  at 


DUNES  ON  THE  ASSINIBOINE  DELTA.  375 

1,250  to  1,255  feet,  and  it  appears  to  have  been  eroded  at  the  time  of  the 
formation  of  the  Herman  beach  hb  in  Brandon,  when  the  level  of  Lake 
Agassiz  was  approximately  at  this  height.  Three  to  4  miles  west  of  Bran- 
don the  road  to  Kemnay  crosses  another  watercourse  of  similar  character, 
diminishing  from  IJ  miles  to  a  half  mile  in  width  within  2  miles  from  north- 
west to  southeast,  passing  from  the  Assiniboine  Valley  to  the  head  of  Bakers 
or  Stony  Creek.  Its  bed,  which  is  strewn  with  plentiful  bowlders,  showing 
that  the  erosion  here  extended  through  the  stratified  gravel  and  sand  to  till, 
is  about  1,270  feet  above  the  sea,  and  marks  nearly  the  Herman  h  stage 
of  Lake  Agassiz,  being  aboiit  30  and  40  feet,  respectively,  below  the 
adjoining  areas  of  delta  gravel  and  sand  on  the  east  and  west.  In  3  miles 
westward  to  Kemnay  this  delta  expanse  rises  50  to  60  feet,  and  continues  to 
ascend  more  slowly  in  the  next  3J  miles  to  1,390  and  1,400  feet  in  sections 
1,  12,  and  13,  township  10,  range  21.  Thence  the  surface  for  the  next  6 
miles  westward,  about  Alexander,  including  nearly  all  of  this  township  and 
the  east  edge  of  that  next  west,  is  till. 

Many  portions  of  the  fine  sand  deposits  of  the  Assiniboine  delta  have 
been  channeled  and  piled  by  the  wind  in  dunes  from  10  to  75  feet  high, 
mostly  covered  with  bushes  and  a  scanty  growth  of  herbaceous  plants,  but 
in  part  destitute  of  vegetation,  which  is  prevented  from  obtaining  a  foot- 
hold by  the  drifting  of  the  sand.  On  the  southeast  part  of  this  area  these 
sand  hills,  seldom  exceeding  30  or  40  feet  in  height,  occur  in  sections  1  to 
4,  township  7,  range  7,  and  are  thence  frequent  northward  upon  a  width  of 
10  miles  northeast  of  the  Boyne  and  southeast  of  the  Assiniboine.  On  the 
north  side  of  the  Assiniboine  the  most  eastern  dunes  extend  to  within  3 
miles  southwest  of  Portage  la  Prairie.  Both  these  tracts  lie  on  the  lower 
part  of  the  eastern  slope  of  the  delta,  and  thence  westward  dunes  are  found 
here  and  there  over  this  entire  slope.  Even  where  no  distinct  hillocks  and 
ridges  have  been  formed,  the  surface  is  often  channeled  and  ridged  in  hol- 
lows and  elevations  of  a  few  feet,  though  now  wholly  grassed  or  covered 
with  bushes  or  small  poplar  groves.  Upon  the  delta  plateau  tracts  of 
dunes,  commonly  raised  20  to  40  feet  above  the  general  level,  interspersed 
with  occasional  smooth  areas  where  the  original  surface  remains  undis- 
turbed, extend  on  the  south  side  of  the  Assiniboine  from  the  Cypress  to 


376  THE  GLACIAL  LAKE  AGASSIZ. 

the  Souris,  occupying  a  width  that  varies  from  1  to  5  miles.  Their  south- 
em  limit  is  about  4  miles  north  of  Holland,  3  miles  north  of  Cypress  River 
station,  and  2  miles  north  of  Grlenboro.  One  to  4  miles  west  of  the  mouth 
of  the  Souris  an  isolated  tract  of  dunes  about  3  miles  long  from  southeast 
to  northwest  is  crossed  by  Spring  Creek  near  its  mouth.  North  of  the 
Assiniboine  much  of  its  delta  plateau  is  occupied  by  dunes,  which  extend 
north  to  the  White  Mud  River.  Their  most  northern  area  is  a  belt  that 
reaches  north  of  this  stream  through  sections  12,  13,  24,  and  25,  township 
15,  range  15,  to  the  junction  of  Hazel  and  Snake  creeks.  But  the  north- 
western part  of  this  plateau  includes  a  belt  of  smooth  and  fertile  land,  sev- 
eral miles  wide,  extending  from  Carberry  north  and  northwest  to  the  limit 
of  the  delta.  Also,  from  Douglas  and  Chater  southeastward  a  belt  of  good 
agricultural  land,  free  from  dunes  upon  a  width  of  3  to  5  miles,  reaches  15 
miles  along  the  northeast  side  of  the  Assiniboine.  On  the  extreme  western 
and  highest  part  of  this  delta  conspicuous  sand  hills  rise  60  feet  above  the 
adjoining  sixrface,  with  their  crests  about  1,445  feet  above  the  sea,  in  sec- 
tions 6  and  7,  township  10,  range  20,  2  to  3  miles  southwest  of  Kemna)^, 
and  lower  hillocks  of  wind-blown  sand  continue  from  these  2  miles  to  the 
southeast. 

Within  6  miles  from  the  dunes  last  noted,  and  from  the  boundary  of 
this  Assiniboine  delta,  after  crossing  a  belt  of  till  that  reaches  about  3  miles 
east  and  the  same  distance  west  from  Alexander  station,  the  Canadian 
Pacific  Railway,  thence  west  to  Griswold,  Oak  Lake,  and  Virdeu,  lies  upon 
the  delta  which  was  brought  into  the  Lake  Souris  by  the  Assiniboine.  In 
townships  9  and  10,  range  22,  and  township  9,  range  23,  including  the 
vicinity  of  Griswold,  this  deposit  consists  of  fine  clayey  silt  and  sand,  hav- 
ing a  moderately  undulating  or  rolling  surface,  with  broad,  smooth  swells 
elevated  10  to  30  feet  above  the  depressions,  their  tops  being  1,400  to  1,435 
feet  above  the  sea.  Tlu-ee  to  7  miles  southwest  of  Griswold  this  delta  has 
been  much  channeled  and  uplifted  by  the  wind  in  sand  hills,  which  thence 
continue  10  miles  southeast  along  the  north  side  of  Plum  Creek  to  section 
11,  township  8,  range  22,  4  miles  west  of  Plum  Creek  village.  The  crests  of 
these  dunes  are  1,420  to  1,430  feet  above  the  sea,  being  30  to  40  feet  above  the 
adjoining  sm-face.     Nearly  all  of  them  are  now  covered  by  grass  and  bushes. 


SOURIS  DELTA  AND  THE  BIG  SLOUGH.  377 

The  Assiniboine  delta  of  Lake  Souris  has  a  length  of  about  85  miles, 
extending  from  the  north  end  of  this  glacial  lake  south-southeasterly  along 
the  Assiniboine  to  its  eastward  bend  and  beyond  to  Plum  Creek  and  the 
Souris  River.  Its  width  ranges  from  5  to  25  miles,  averaging  about  12 
miles.  This  delta  is  doubtless  shallower  than  that  of  Lake  Agassiz,  but  if 
its  average  thickness  is  25  feet  upon  this  area  of  1,000  square  miles,  its 
volume  is  about  5  cubic  miles. 

An  ancient  watercourse,  now  occupied  by  a  body  of  water  called  the 
Big  Slough,  13  miles  long  and  mostly  20  to  50  rods  wide,  but  in  its  west 
part  about  three-fourths  of  a  mile  wide,  extends  from  southwest  to  north- 
east 9  miles  tlu-ough  this  delta  of  Lake  Souris  and  thence  continues  4 
miles  east  through  an  area  of  till.  Its  west  end  is  2  miles  southwest  of 
Griswold  and  its  east  end  about  a  half  mile  east  of  Alexander,  its  whole 
extent  being  on  the  south  side  of  the  railwa}".  Its  elevation  in  the  stages 
of  low  and  high  water  ranges  from  1,385  to  1,388  feet,  and  its  depth  at  low 
water  varies  from  2  to  6  or  8  feet.  The  shores  of  the  Bigr  Slouch  rise  in 
gentle  slopes  15  to  20  feet  in  20  to  30  rods,  to  the  general  level,  not  having 
the  usual  steepness  of  banks  undermined  by  streams;  yet  it  doubtless 
marks  the  course  of  a  stream  that  outflowed  at  one  time  westward  into 
Lake  Som-is  from  a  small  glacial  lake  north  of  the  Brandon  Hills,  and  of  a 
later  stream  that  flowed  in  the  opposite  direction,  eastward  from  the  basin 
of  Lake  Souris  into  the  Brandon  glacial  lake,  before  that  became  merged 
in  Lake  Agassiz  by  the  departure  of  the  ice-sheet.  The  succession  of 
events  indicated  by  this  channel,  together  with  that  of  the  present  Souris 
and  with  the  great  glacial  watercourse  of  Langs  Valley,  is  as  follows: 
Lake  Souris  outflowed  eastward  by  Langs  Valley,  Pelican  Lake,  and  the 
Pembina  River  until  the  recedinof  ice  formed  a  lake  north  of  the  Tiffer 
Hills  and  east  of  the  Brandon  Hills,  which,  outflowing  south  to  the  Som-is, 
cut  a  deep  gorge  through  the  Tiger  Hills  moraine,  where  the  Souris  now 
flows  through  it  to  the  north.  Similarly,  north  of  the  Brandon  Hills,  a 
lake  was  probably  held  by  the  barrier  of  the  ice  during  its  recession  from 
Alexander  east  by  Kemnay  and  Brandon,  outflowing  westward  to  the  Lake 
Souris  by  the  course  of  the  Big  Slough.  As  soon  as  the  continued  glacial 
recession  left  the  Brandon  Hills  wholly  uncovered  from  the  ice,  these  lakes 


378  THE  GLACIAL  LAKE  AGASSIZ. 

on  the  east  and  north  were  merged  in  one,  and  the  outflow  from  the  lake  so 
formed  passed  south  tlu-ough  the  Tiger  Hills  to  Langs  Valley  until  that 
channel  was  cut  down  nearlj^  to  1,350  feet.  During  this  stage  of  a  contin- 
uous lake  east  and  north  of  the  Brandon  Hills,  this  independent  part  of 
Lake  Agassiz,  before  it  was  merged  with  the  main  body  of  this  lake  by  the 
recession  of  the  ice  from  the  east  end  of  the  Tiger  Hills,  received  an  exten- 
sive delta,  already  described  as  the  highest  portion  of  the  Assiniboine  delta 
in  the  vicinity  of  Brandon  and  Kemnay,  consisting  partly  of  modified  drift 
from  the  retreating  ice  and  partly  of  fine  sand  and  silt  brought  by  a  stream 
then  flowing  east  from  the  Lake  Souris  delta  along  the  Big  Slough.  The 
tribute  of  the  latter  is  spread  over  an  area  of  several  square  miles  south- 
west of  Kemnay,  and  upon  it  are  raised  the  conspicuous  dunes  of  sections 
6  and  7,  township  10,  range  20.  With  the  retreat  of  the  ice  northward 
from  Treherne,  the  Brandon  lake  was  lowered  nearly  100  feet  to  the  level 
of  Lake  Agassiz  in  its  Herman  h  stage.  For  a  short  time  the  Souris  prob- 
ably continued  to  flow  southeastward  through  Langs  Valley  until  the 
deposition  of  the  alluvium,  perhaps  10  or  15  feet  thick,  brought  into  that 
valley  by  Dunlops  Creek,  4  miles  east  of  the  elbow  of  the  Souris,  raised  a 
barrier  a  few  feet  higher  than  the  gap  that  had  been  cut  through  the  Tiger 
Hills  north  of  the  elbow,  whereby  the  river  was  turned  through  this  gap, 
which  it  has  since  eroded  100  to  150  feet  deeper. 

The  modified  drift  and  alluvium  that  form  the  plain  of  coarse  gravel 
and  sand  sloping  eastward  from  Kemnay  to  Brandon  and  reach  along  the 
north  side  of  the  Assiniboine  to  Douglas  were  probably  deposited  mostly 
while  the  barrier  of  the  waning  ice-sheet  stretched  from  the  Tiger  Hills  to 
Riding  Mountain,  inclosing  on  its  west  side  a  lake  that  afterwards  became 
the  bay  of  Lake  Agassiz  covering  the  Assiniboine  delta,  but  was  then  held 
about  100  feet  above  Lake  Agassiz,  to  which  it  outflowed  by  the  way  of 
Langs  Valley  and  the  Pembina.  The  deposition  of  this  highest  part  of  the 
Assiniboine  delta,  lying  above  the  Herman  hh  beach  observed  in  Brandon, 
appears  to  have  been  in  progress  through  a  considerable  period,  begimiing 
when  this  Brandon  glacial  lake  was  held  at  an  elevation  of  about  1,400 
feet,  and  continuing  while  it  was  lowered  nearly  150  feet.  During  this 
time  the  Brandon  Lake  had  tlu-ee  outlets:  first,  from  its  two  parts,  respec- 


THE  BRANDON  GLACIAL  LAKE.  379 

tively,  westward  by  the  Big  Slough  and  southward  across  the  Tiger  Hills 
moraine;  second,  from  the  whole  lake,  when  these  parts  became  confluent, 
by  the  southward  one  of  these  outlets,  namely,  the  gap  where  the  Souris 
now  flows  through  the  Tiger  Hills;  and,  third,  by  confluence  with  Lake 
Agassiz,  when  this  was  permitted  by  the  recession  of  the  ice.  Much  modi- 
fied drift  was  probably  brought  into  the  Brandon  Lake  by  drainage  along 
the  course  of  the  Little  Saskatchewan,  and  it  is  significant  that  in  the  line 
of  continuation  of  the  valley  of  that  stream  the  plain  between  Kemnay 
and  Brandon  is  crossed  by  a  broad  watercourse,  which  was  evidently 
eroded  after  this  lake  became  merged  in  Lake  Agassiz,  thereby  falling 
nearly  100  feet  below  its  former  level  when  outflowing  through  Langs 
Valley,  but  before  the  Assiniboine  had  cut  its  broad  valley  through  this 
delta.  More  exactly,  as  before  noted,  this  watercourse  seems  referable  to 
the  Herman  h  stage  of  Lake  Agassiz,  and  the  similar  watercourse  about  20 
feet  lower,  passing  throvigh  the  west  and  south  parts  of  Brandon,  was  prob- 
ably formed  during  the  Herman  hh  stage.  During  these  two  stages  of  the 
lake  the  principal  expanse  of  the  Assiniboine  delta  was  formed,  Ijang  only 
slightly  below  the  levels  which  the  lake  then  had. 

At  the  time  of  formation  of  the  Herman  hb  beach  the  Assiniboine 
had  already  eroded  a  deep  and  wide  valley  in  its  delta  at  Brandon,  and 
as  Lake  Agassiz  sank  to  successive  lower  levels  this  erosion  continued, 
cutting  at  least  the  lower  part  of  the  great  valley  200  to  300  feet  deep,  in 
which  this  river  flows  above  Brandon,  and  weai-ing  its  channel  to  a  nearly 
equal  depth  through  its  own  delta.  The  Canadian  Pacific  Railway  ci'osses 
the  Assiniboine  about  2  miles  east  of  Brandon,  near  the  division  between  the 
main  area  of  its  delta  in  Lake  Agassiz  and  the  deep  portion  of  its  ujjper 
valley.  There  the  high  land  on  each  side  of  the  river  recedes,  allowing 
the  descent  to  the  stream  to  be  made  by  easy  grades  on  each  side  and 
supplying  upon  the  gradual  slope  south  of  the  river  the  beautiful  site  of 
Brandon.  No  other  point  so  favorable  for  this  crossing  exists  within  60 
miles  to  the  east  or  west,  where  the  river  flows  in  a  deeper  and  narrower 
valley.  The  greater  part  of  this  delta  was  modified  drift  derived  from  the 
melting  ice-sheet  on  the  upper  part  of  the  basin  of  the  Assiniboine  and  on 
Riding  Mountain,  being  carried  down  from  the  latter  area  by  the  Bird- 


380  THE  GLACIAL  LAKE  AGASSIZ. 

tail  Creek  aud  the  Oak  and  Little  Saskatchewan  rivers  (p.  190).  It  was 
deposited  in  this  delta  chiefly  during  the  early  Herman  stages  of  the  lake, 
as  is  indicated  by  the  elevation  of  the  outer  part  of  its  principal  expanse; 
and  its  deposition  continued  until  the  ice-sheet  was  melted  away  on  Riding 
Mountain  and  the  upper  Assiniboine.  The  erosion  of  the  Assiniboine  Valley 
above  Brandon  also  supplied  a  considerable  part  of  the  delta.  During  the 
ensuing  stages  of  Lake  Agassiz,  to  those  of  Gladstone  and  Buruside, 
the  border  of  this  great  delta  was  undergoing  erosion  by  the  lake  waves 
and  shore  currents,  by  which  its  outer  portion  was  spread  in  more  gentle 
slopes,  extending  farther  into  the  lake,  and  much  of  it  was  swept  southward 
along  the  shore. 

By  this  erosion  of  the  sloping  face  of  the  delta,  and  especially  by 
earlier  transportation  into  the  deep  water  of  the  lake  while  the  gravel  and 
sand  were  being  deposited  in  its  western  embayment  between  the  Tiger 
Hills  and  Riding  Mountain,  a  large  expanse  of  fine  clayey  sediment  of  the 
same  origin  with  this   delta  was   spread  far  into  the  lake,   extending  to 
the  east  beyond  the  Red  River  and  to  the  south  beyond  the  international 
boundary.     This  deposit  of  lacustrine  silt  covers  the  till  from  the  eastern 
and  southeastern  limits  of  the  delta,  as  before  defined,  to  the  low  ridge  first 
east  of  the  Red  River,  about  10  miles  east  of  Emerson,  while  similar  sedi- 
ments cover  the  central  part  of  the  Red  River  Valley  southward  to  Goose 
Rapids,  more  than  100  miles  east-southeast  from  this  delta.     Toward  the 
north  and  northeast,  lacustrine  sediments  and  subsequent  alluvial  deposits 
associated  with  the  Assiniboine  delta  cover  the  nearly  flat  country  north 
from  Burnside,  Portage  la  Prairie,  and  High  Bluff"  to  Lake  Manitoba.     On 
this  area  the  watershed  between  the  Assiniboine  and  Lake  Manitoba  is  very 
low,  and  the  river  has  sometimes  ovei-flowed  its  low  banks,  sending  part  of 
its  floods  north  to  the  lake,  which  in  turn  in  its  highest  stages  has  occa- 
sionally become  for  a  short  time  tributary  to  the  lower  part  of  this  river. 
But  the  transportation  of  the  silt  in  the  lake  was  of  less  extent  in  this 
direction  than  to  the  east  and  south,  as  is  shown  by  areas  of  till  f)n  both 
sides  of  the  Big  Grass  Marsh,  west  of  Lake  Manitoba,  and  from  townships  13 
and  14,  range  5,  southeast  of  this  lake,  eastward  to  Shoal  Lake,  Stonewall, 
and  Lower  Fort  Garry. 


THE  ASSINIBOINE  DELTA.  381 

Five  to  10  miles  west  of  Portage  la  Prairie  till  with  frequent  bowlders 
forms  the  surface,  or  is  underlain  only  to  the  depth  of  a  few  feet  by  the 
sediments  associated  with  this  delta.  Again,  10  miles  farther  west,  the  sandy 
eastern  slope  of  the  delta  in  the  vicinity  of  McGregor  shows  very  rarely 
projecting  bowlders,  the  size  of  the  few  noticed  being  from  2  to  6  feet  in 
diameter.  They  probably  lie  on  till  that  has  been  somewhat  eroded  by  the 
lake  waves,  so  that  these  bowlders  are  not  embedded  in  it  as  usual,  while 
the  sand  and  silt  afterward  spread  thereon  the  surface  are  not  sufficiently 
thick  to  conceal  them.  No  bowlders  were  elsewhere  seen  on  the  general 
surface  of  the  delta  and  of  the  great  area  of  associated  lacustrine  silt,  nor  in 
any  observed  sections  of  these  deposits. 


CHAPTER  VII. 
LOWER  BEACHES  WITH  SOUTHWARD  OUTFLOW. 

Extensive  portions  of  the  lower  beaches  that  were  formed  while  Lake 
Agassiz  outflowed  to  the  south  have  been  exactly  mapped,  with  determina- 
tion of  their  heights  by  leveling.  These  are  described  in  the  following 
pages,  the  successive  beaches  being  treated  in  their  order  from  higher  to 
lower.  Four  well-defined  levels  of  the  glacial  lake  are  exhibited  by  the 
shore-lines  of  its  southern  part,  which  have  been  named,  from  localities  of 
their  typical  development  in  Minnesota,  the  Norcross,  Tintah,  Campbell,  and 
McCauleyville  beaches.  In  advancing  northward  each  of  these  beaches, 
similarly  with  the  uppermost  or  Herman  series  of  beaches  described  in  the 
last  chapter,  is  found  to  become  subdivided  into  two  or  more  separate  and 
distinct  beaches  or  shore-lines. 

The  attempts  here  made  to  correlate  these  multiple  northern  shores  of 
Lake  Agassiz  with  the  fewer  southern  shore-lines  rest  on  the  determination 
of  many  altitudes  along  the  course  of  these  former  planes  of  the  ancient 
lake  levels.  The  several  shores,  both  at  the  south  and  north,  were  separated 
from  each  other  partly  by  the  progressing  erosion  of  the  outlet,  and  partly 
by  the  gradual  decrease  of  the  attraction  of  the  lake  by  gravitation  toward 
the  waning  ice-sheet,  but  more  by  the  intermittent  uplifting  of  this  part  of 
the  earth's  crust,  due  evidently  to  its  relief  from  the  pressure  of  the  depart- 
ing ice.  Considerable  ii-regularities  in  this  uplifting  would  be  expected,  by 
which  the  gradients  of  northward  ascent  of  the  beaches  would  be  made 
variable,  being  comparatively  steep  or  changing  abruptly  in  elevation  in 
some  places,  and  elsewhere  being  of  small  amount  or  even  showing  a 
reversal,  that  is,  a  descent  toward  the  north.  In  this  survey,  however,  I 
have  not  discovered  any  remai'kable  divergences  or  exceptions  from  an 
approximate  parallelism  of  the  beaches.  The  northward  ascent  of  the 
highest  beach  in  the  Herman  series,  ranging  from  6  to  18  inches  per  mile, 

382 


THE  NOECEOSS  BEACHES  IN  MINNESOTA,  383 

is  gradually  diminished  iu  the  successive  lower  shore-lines,  each  having 
slightly  less  ascent  than  the  preceding,  to  the  McCauleyville  beaches, 
which  rise  1  to  3  or  4  inches  per  mile.  In  all  of  these  shore-lines  the 
rate  of  ascent  is  found  to  increase  as  one  advances  from  south  to  north. 


BEACHES    or    THE    NORCEOSS    STAGES. 

FROM    LAKE    TRAVERSE    TO    NORCROSS    AND    MAPLE    LAKE,  MINNESOTA. 

(plates   XXIII   TO   XXVI.) 

The  Norcross  shore-line  of  Lake  Agassiz  lies  near  the  Herman  shore 
on  the  slope  of  eroded  till  which  reaches  about  4  miles  east  from  the 
northeast  end  of  Lake  Traverse.  Thence  eastward,  from  near  the  south 
line  of  section  35,  townsliip  127,  range  47,  Lake  Agassiz  was  very  shallow 
during  the  Herman  stage,  and  its  fall  of  20  feet,  or,  to  sjjeak  with  more 
correctness,  the  rise  of  the  land  to  this  amount,  between  the  times  of 
formation  of  the  Herman  and  Norcross  shore-lines,  caused  the  lake  margin 
to  fall  back  about  6  miles  from  its  most  southern  portion.  The  Norcross 
beach,  having  a  height  of  1,043  feet  above  the  sea,  is  crossed  by  the  Fargo 
and  Southern  branch  of  the  Chicago,  Milwaukee  and  St.  Paul  Railway  at 
a  distance  of  nearly  1  mile  north  of  Dumont.  It  is  here  a  very  slight 
ridge  of  gravel  and  sand,  rising  only  2  or  3  feet  above  the  uniform  slope 
of  the  very  flat  expanse  of  till. 

Within  the  next  3  miles  to  the  east  this  beach  becomes  more  con- 
spicuous and  has  been  excavated  in  several  places  to  obtain  sand  for 
masons'  use.  In  section  12,  Croke,  it  is  a  typical  beach  ridge  about  25 
rods  wide,  with  a  descent  of  5  or  6  feet  from  its  broadly  rounded  crest 
toward  the  north  and  2  or  3  feet  toward  the  south.  At  an  excavation  near 
the  line  between  sections  11  and  12  its  crest  has  a  height  of  1,045  feet. 
The  depth  of  the  beach  sand  and  fine  gravel,  containing  pebbles  up  to  an 
inch  in  diameter,  is  5  feet,  with  till  beneath. 

Thence  the  Norcross  beach  ridge,  mostly  2  to  4  feet  high,  runs  east 
to  Twelve  Mile  Creek,  and  beyond  turns  to  the  north  and  northeast.  In 
sections  32  and  33,  Clifton,  its  height  is  1,038  to  1,041  feet  above  the  sea; 


384  THE  GLACIAL  LAKE  AGASSIZ. 

and  in  the  northwest  quarter  of  section  26,  this  township,  1,042  feet,  with 
descent  of  about  5  feet  on  each  side.  Crossing  next  the  northwest  part  of 
Logan,  its  crest  is  at  1,043  to  1,048  feet. 

Between  a  half  mile  and  1  mile  south  of  Norcross  this  beach  is  admi- 
rably developed,  the  elevation  of  its  higher  portions  being  1,045  to  1,048 
feet,  from  which  there  is  a  descent  of  3  to  5  feet  eastward  and  of  10  feet 
westward.  It  is  a  massive  gravel  and  sand  ridge,  about  25  rods  wide, 
including  its  slopes,  lying  on  till. 

Nearly  the  same  features  characterize  it  also  at  Norcross  station,  where 
its  height  is  1,041  feet.  There  is  a  depression  3  feet  lower  on  the  south- 
east, and  the  surface  10  to  15  rods  northwest  from  the  top  of  the  beach,  on 
the  side  where  the  lake  was,  has  a  height  of  1,034  to  1,036  feet.  Thence  a 
very  smooth  plain  of  till  descends  to  Tintah,  Campbell,  and  the  Red  River 
at  Breckem-idge.  About  50  rods  northeast  from  Norcx'oss  station  the  beach 
attains  its  greatest  height  in  this  village,  1,045  feet.  It  is  a  rounded  low 
ridge  of  sand  and  gravel,  lying  on  an  area  of  till,  and  closely  resembles  the 
Herman  beach,  which  lies  nearly  parallel  with  it  at  a  distance  of  3  miles 
to  the  east. 

Thence  northward  the  com-se  of  the  Norcross  beach  has  been  mapped, 
mostly  without  leveling,  to  the  Red  River,  which  it  crosses  near  the  north- 
east comer  of  section  31,  township  132,  range  44,  in  the  west  edge  of 
Ottertail  County.  Tlu-ough  this  extent  of  about  25  miles  the  Norcross 
shore-line  is  marked  almost  continuously  by  a  distinct  beach  ridge,  3  to  5 
feet  above  the  land  on  the  east,  and  twice  as  high  above  the  adjoining 
surface  at  the  west  which  was  covered  by  the  lake  while  this  beach  was 
being  formed.  Its  distance  from  the  Herman  beach  on  the  east  varies 
mainly  from  3  to  2  miles,  but  between  1  and  5  miles  south  of  the  Red 
River  the  two  beaches  are  only  1  mile  apart. 

Where  the  Norcross  beach  is  crossed  by  the  road  from  Fergus  Falls  to 
Campbell,  near  the  west  line  of  section  29,  Western,  it  has  an  elevation 
very  nearly  1,045  feet  above  the  sea.  It  is  a  wave-like  ridge  of  sand  and 
gravel,  about  15  rods  wide,  with  nearly  flat  surfaces  of  till  or  bowlder- 
clay  on  each  side.  In  crossing  it  the  ascent  from  the  east  is  about  5  feet 
and  the  descent  toward  the  west  about  10  feet.     In  sections  19,  18,  and  7, 


THE  NOECROSS  BEACHES  IN  MINNESOTA.         385 

Western,  where  this  beach  ridge  runs  nearly  due  north,  the  height  of  its 
crest,  according  to  my  levehng,  is  1,043  to  1,045  feet. 

Continuing  northward  beyond  the  Red  River,  the  Norcross  shore-line 
traverses  the  northeast  corner  of  township  132,  range  45,  passing  west  of  a 
small  lake  whicli  lies  a  mile  south  of  the  Northern  Pacific,  Fergus  Falls 
and  Black  Hills  Railroad.  Thence  its  course  is  nearly  north-northwest 
across  the  next  two  townships  in  this  range;  but  in  Tanberg  and  through 
the  next  10  miles  to  Humboldt  (the  next  township  east  of  Barnesville)  it 
runs  in  a  nearly  direct  course  only  a  few  degrees  west  of  north.  On  the 
west  side  of  the  very  remarkable  marshy  and  springy  belt  which  lies  just 
within  the  Herman  shore-line  in  Akron  and  Tanberg,  the  Norcross  beach 
rises  as  a  ridge  of  gravel  and  sand  a  few  feet  high,  forming  in  considerable 
part  the  boundary  between  the  bogs,  springs,  and  numerous  watercom-ses 
on  the  east  and  the  firm  land,  capable  of  cultivation,  on  the  west.  In  Tan- 
berg it  passes  along  the  east  border  of  sections  32,  29,  20,  and  17,  having 
at  its  crest  a  height  of  1,050  to  1,060  feet  above  the  sea. 

Close  east  of  the  Norcross  beach  ridge  a  large  spring  in  the  northwest 
corner  of  the  southwest  quarter  of  section  28,  Tanberg,  having  a  diameter 
of  about  15  feet  and  depth  of  10  feet,  issues  with  so  strong  a  current  as  to 
throw  up  the  sand  at  its  bottom  to  a  height  of  2  or  3  feet  into  the  water. 
A  creek  5  to  15  feet  wide  and  1  to  3  feet  deep,  in  which  many  pickerel 
live,  flows  from  this  spring  southward  along  the  east  side  of  the  beach 
about  a  mile,  then  turning  west  into  the  southeast  quarter  of  section  32, 
where  it  sinks  into  the  gravelly  and  sandy  ground  and  is  lost. 

About  1^  miles  east  from  Barnesville  the  Norcross  beach  is  well 
exhibited  at  D.  D.  Daniels's  house,  in  the  southeast  quarter  of  section  20, 
Humboldt,  being  a  low,  smoothly  rounded  ridge  of  gravel  and  sand,  with 
the  elevation  of  1,061  feet  above  the  sea. 

Through  Riverton  and  in  sections  35  and  26,  township  140,  range  46, 
the  eroded  western  border  of  the  delta  of  the  Buffalo  River  marks  the 
shore  of  Lake  Agassiz  at  the  time  of  the  Norcross  beach. 

In  the  west  part  of  section  24,  township  140,  range  46,  and  for  4  miles 
northward,  the  Norcross  beach  lies  only  1  mile  to  a  half  mile  west  of  the 
Herman  beach,  and  is  about  50  feet  lower.  The  terrace-like  area  between 
MON  XXV 25 


386  THE  GLACIAL  LAKE  AGASSIZ. 

these  beaches  is  strewn  with  occasional  bowlders  up  to  6,  8,  or  10  feet  in 
diameter  and  rarely  of  larger  size,  much  more  abundant  than  upon  the 
average  surface  of  the  till  in  this  region,  indicating  that  the  surface  there 
has  been  considerably  eroded  by  the  waves  of  the  lake. 

The  elevation  of  the  foot  of  the  western  slope  of  the  upper  or  Herman 
beach  along  the  north  part  of  the  east  line  oi  township  140,  range  46,  is 
1,095  to  1,100  feet.  Crest  of  the  Norcross  beach  in  section  12  of  this 
township,  6  miles  north  of  Muskoda,  1,080  feet,  and  along  the  distance  of 
3  miles  tlu-ongh  sections  13,  12,  and  1  it  varies  from  1,075  to  1,085  feet. 
In  section  31,  Keene,  its  height  is  1,085  feet.  Like  the  Herman  beach,  it 
is  a  low,  smoothly  rounded  ridge  of  gravel  and  sand,  usually  having  a 
depression  of  3  to  5  feet  or  more  at  its  east  side. 

Tlu'ough  the  west  part  of  Keene  the  Norcross  beach  is  1  to  1^  miles 
west  of  the  upper  beach.  Thence  it  crosses  Hagen  in  a  north-northeast 
course,  lying  2  to  3  miles  northwest  and  west  of  the  upper  beach.  Its 
height  in  these  townships  is  approximately  1,080  feet. 

Both  the  Herman  and  Norcross  beaches  in  this  northern  part  of  Clay 
County,  between  the  Buffalo  River  and  the  South  Branch  of  the  Wild  Rice, 
have  an  altitude  notably  higher  than  would  coincide  with  a  uniform  ascent 
of  these  shores  from  Lake  Traverse  to  Maple  Lake.  The  normal  height  of 
the  Herman  beach  on  this  tract  would  be  15  to  20  feet  below  where  that 
beach  is  found;  and  the  Norcross  beach  lies  fully  10  feet  above  where  it 
would  be  expected.  The  uplift  of  the  earth's  crust  here  was  disproportion- 
ate by  these  amounts  with  its  upward  movement  along  the  other  explored 
portions  of  the  eastern  shore  of  this  glacial  lake. 

Proceeding  onward  tlu-ough  Norman  County,  the  position  of  the  Nor- 
cross beach  is  shown  approximately  on  PI.  XXV,  but  its  course  has  not 
been  exactly  mapped.  Two  small  beach  ridges,  having  nearly  the  same 
height,  probably  belonging  to  the  Norcross  stages  of  this  lake,  were  noted, 
running  nearly  from  south  to  north,  in  the  east  half  of  section  8,  Wild 
Rice  Township.  Again,  on  the  north  line  of  Norman  County,  in  leveling 
from  Rolette  eastward,  a  well-marked  beach  ridge,  10  to  15  rods  wide, 
with  a  depression  of  4  to  5  feet  on  its  east  side,  was  crossed  on  the  western 
edge  of  the  delta  of  the  Sand   Hill   River,  near  the  northeast  corner  of 


THE  NOECROSS  BEACHES  IN  MINNESOTA.         387 

Spring  Creek  Township.  This  beach,  which  appears  to  be  one  of  the 
upper  Tintah  shore-hues,  has  a  height  of  1,060  feet  above  the  sea.  About 
a  quarter  of  a  mile  farther  east  beach  gravel  and  sand  are  spread  in  a  some- 
what flattened,  broad  ridge,  at  a  height  of  1,070  to  1,073  feet,  bounded  by  a 
hollow  2  or  3  feet  lower  on  the  east.  This  probably  belonged  to  a  slightly 
hio'her  Tintah  beach  of  Lake  Ao^assiz.  The  Norcross  shore-lines  are  not 
distinctly  exhibited  here  on  the  very  gradual  ascent  of  the  delta  sand 
deposit,  which  extends  eastward  across  the  next  mile  or  more  to  tracts 
of  dunes. 

On  the  Fosston  branch  of  the  Great  Northern  Railway,  about  14  miles 
north  of  the  last  described  locality  and  on  the  same  latitude  with  the  east- 
wardly  curving  Herman  beaches  north  of  Maple  Lake,  tlu-ee  small  beach 
ridges  are  crossed  about  2^  miles  east  of  Benoit,  the  elevation  of  their 
crests  being  successively  1,062,  1,069,  and  1,069  feet  in  their  order  from 
west  to  east.  These  probably  represent  the  upper  Tintah  beach.  One  and 
a  quarter  miles  farther  east  a  more  massive  beach  is  crossed,  with  its  crest 
at  1,092  feet,  which  is  probably  the  lowest  Norcross  shore-line.  Other 
beach  ridges  crossed  IJ  miles  and  If  miles  east  of  the  last,  with  crests 
respectively  at  1,114  and  1,120  feet,  are  apparently  referable  to  upper 
Norcross  stages  of  the  lake.  The  next  beach  noted  on  this  railroad,  three- 
quarters  of  a  mile  farther  east,  at  the  height  of  1,142  feet,  belongs  to  the 
lower  portion  of  the  Herman  series. 

In  the  southeast  part  of  Lake  Pleasant  Township  the  lower  Norcross 
shore  is  marked  by  a  belt  of  gravel  and  sand  about  half  a  mile  wide, 
extending  from  the  southwest  to  the  northeast  and  east,  having  an  elevation 
in  section  27  of  1,083  to  1,095  feet. 

My  only  further  observation  of  shore-lines  referable  to  the  Norcross 
stages  of  the  eastern  border  of  Lake  Agassiz  is  within  1  to  2  miles  west  of 
St.  Hilaire,  where  indistinct  lower  Norcross  beaches,  at  a  height  of  about 
1,090  feet,  are  crossed  by  the  St.  Hilaire  branch  of  the  Great  Northern 
Railway. 

Thence  northward  the  Norcross  shores  lie  in  a  wooded  country  where 
they  can  not  pi-acticably  be  traced.  From  the  altitudes  of  the  region  it  is 
known  that,  after  passing  northward  and  then  eastward  around  the  higher 


388  THE  GLACIAL  LAKE  AGASSIZ. 

district  of  tlie  Beltrami  Island,  they  curve  east-southeasterly  to  the  valley 
of  the  Raiuy  River  and  the  vicinity  of  Rainy  Lake,  and  thence  sweep 
back  to  the  northwest  and  north  across  the  hilly  Archean  region  east  of  the 
Lake  of  the  Woods. 

THKOUGH  NORTH  DAKOTA,  FROM  LAKE  TRAVERSE  TO  THE  INTERNATIONAL 

BOUNDARY. 

(plates   XXIII  AND   XXVII-XXX.) 

On  and  near  the  line  between  South  and  North  Dakota,  at  a  distance 
of  3  to  7  miles  west  of  White  Rock  and  the  Bois  des  Sioux,  the  Norcross 
stages  of  Lake  Agassiz  formed  no  less  than  four  separate  and  parallel  beach 
ridges  of  gravel  and  sand,  3  to  8  feet  high,  lying  on  a  surface  of  till.  In 
section  1,  township  128,  range  48,  South  Dakota,  where  these  small  ridges 
run  to  the  northwest  and  north-northwest,  the  elevations  of  their  crests  in 
order  from  west  to  east  are,  first,  1,045  to  1,048  feet  above  the  sea;  second, 
1,043  to  1,045  feet;  third,  1,033  feet;  and,  fourth,  1,030  feet.  The  highest 
beach  of  this  series  passes  about  a  half  mile  west  of  Mr.  L.  H.  Foote's 
house,  which  is  in  the  southeast  corner  of  this  section;  the  second  runs 
about  40  rods  west  of  this  house ;  and  the  third  and  fourth  lie  about  a  thu'd 
of  a  mile  and  a  half  mile  east  of  it,  passing  thence  northward  tlu-ough  the 
northeast  corner  of  this  section  1.  Following  these  beach  ridges  in  their 
curvina:  course  to  the  northwest  and  west-northwest  into  section  28,  town- 
ship  129,  range  48,  the  higher  two  are  found  to  rise  to  1,050  feet,  and  the 
height  of  each  of  the  lower  two  is  increased  by  10  feet.  The  continuations 
of  these  shore-lines  northwestward  to  the  east  side  of  the  Lightnings  Nest 
and  to  the  delta  of  the  Sheyenne  River  have  not  been  exactly  traced.  No 
other  tract  of  the  Norcross  shore  of  this  sovithern  part  of  Lake  Agassiz,  so 
far  as  observed  by  this  survey,  is  thus  marked  by  several  beach  ridges. 
The  multiplication  of  their  number  here,  which  elsewhere  is  commonly 
single  along  all  the  southern  part  of  the  lake,  probably  was  due  to  a  slight 
intermittent  elevation  of  this  tract  while  the  adjacent  country  was  at  rest, 
until  an  uplift  of  the  whole  area  about  Lake  Traverse  led  to  the  formation 
of  the  Tintah  beaches,  the  next  lower  in  the  descending  series. 


NORCROSS  BEACHES  IN  NORTH  DAKOTA.  389 

The  next  definite  observations  of  the  Norcross  sliore  were  on  the 
northern  part  of  the  Sheyenne  delta.  In  the  southwest  corner  of  section 
20,  Helendale  (the  most  northwestern  township  of  Richland  County),  this 
shore  is  marked  by  a  low  beach  ridge,  which  runs  to  the  north-northwest, 
passing  about  20  rods  west  of  Mr.  R.  L.  Porter's  house.  The  crest  of  the 
ridge  rises  5  to  8  feet  above  the  general  surface  of  this  sand  delta,  from 
which  it  is  distinguished  by  being  somewhat  more  channeled  and  heaped 
up  by  the  winds  into  low  dunes,  5  to  10  feet  in  height.  Scattered  cotton- 
woods,  growing  either  alone  or  in  clumps  of  a  few  trees,  are  more  frequent 
along  the  course  of  the  beach  than  on  the  adjoining  tracts.  About  5.  miles 
farther  north,  where  this  shore  is  crossed  by  the  Fargo  and  Southwestern 
Railroad,  3  to  4  miles  west  of  Leonard,  it  bears  three  small  beach  ridges, 
with  crests  at  1,062  to  1,065  feet.  The  most  westerly  and  highest  is  about 
18  rods  wide,  with  a  depression  of  6  feet  on  the  east  and  5  feet  on  tlie  west. 

Thence  northward  across  Cass  County  the  contour  of  tlie  western 
border  of  Lake  Agassiz  shows  that  the  Norcross  shore-line  runs  nearly 
parallel  with  the  Herman  beach,  from  which  it  is  distant  1  to  3  miles  east- 
ward; but  only  small  fragments  of  its  course  have  been  mapped. 

Beginning  in  southwestern  Traill  County,  near  Clifford,  the  Norcross 
shore  has  been  traced  nearly  continuously  more  than  100  miles  north  to 
the  international  boundary.  About  a  mile  northwest  from  Clifford  it  is 
marked  by  a  broad  swell  or  ridge  of  sand  and  gravel,  1  to  2  feet  above  the 
surface  of  till  on  the  west.  Its  elevation  is  1,072  feet  above  the  sea.  One 
to  1^  miles  farther  north,  in  the  south  half  of  section  9,  Norman,  the  shore  • 
deposit  becomes  a  typical  beach  ridge,  with  crest  at  1,075  to  1,077  feet, 
having  a  hollow  of  2  to  4  feet  on  the  west  and  a  descending  slope  on  the 
east  which  falls  30  feet  in  a  third  of  a  mile.  Thence  northward  in  section 
4  of  this  township  the  shore  forms  an  eroded  cliff  of  till,  10  to  15  feet  liigh, 
with  its  base  at  1,075  feet.  In  the  next  mile  to  the  north,  through  section 
33,  township  146,  range  53,  the  line  of  erosion  is  continued,  crossing  an 
area  of  gravel  and  sand.  The  escarpment  rises  about  10  feet  in  4  to  6  rods 
from  east  to  west,  its  base  being  at  1,073  to  1,075  feet,  from  which  a  smooth 
slope  of  sand  and  fine  gravel  falls  about  25  feet  in  two-thirds  of  a  mile  east- 
ward.    In  the  north  part  of  section  20  two  wells  on  this  tract  of  modified 


390  THE  GLACIAL  LAKE  AGASSIZ. 

drift  are  respectively  22  feet  and  31  feet  deep,  wholly  in  loose  and  caving 
sand  and  grravel.  Here  and  tlirousrh  the  west  half  of  section  17  the  Nor- 
cross  beach  is  a  very  finely  developed  ridge,  rising  15  feet  above  its  east 
base  and  descending  4  or  5  feet  on  the  west.  The  elevation  of  its  crest  is 
1,087  to  1,091  feet.  In  the  southeast  part  of  section  7  an  aboriginal  mound, 
5  feet  high  and  60  feet  in  diameter,  is  situated  on  the  top  of  the  beach  ridge; 
and  two  others  of  similar  size  were  seen  within  a  half  mile  to  the  southwest. 

Thence  the  lake  shore  turns  to  a  northwestward  course  for  the  next 
5  miles,  passing  through  the  northeast  comer  of  Primrose  to  the  Middle 
Branch  of  Goose  River,  which  it  crosses  in  the  southwest  part  of  section  27, 
Enger.  In  the  south  half  of  section  2,  Primrose,  the  crest  of  the  beach, 
there  unusually  massive,  is  1,094  feet  above  the  sea,  with  a  descent  of  10 
feet  in  20  to  30  rods  eastward  and  of  5  feet  in  a  shorter  distance  to  the 
west.  Passing  northward  through  Enger  Township,  this  shore  bears  a  typ- 
ical beach  ridge  in  sections  22, 15,  9,  and  3,  with  crest  at  1,080  to  1,085  feet 

Across  the  large  delta  of  sand  and  silt  which  extends  from  McCanna 
and  Larimore  southward  beyond  Hatton,  the  Norcross  shore  is  indistinct 
in  portions  of  its  course,  but  elsewhere  has  a  well-defined  beach  ridge. 
Thi'ough  sections  8  and  5,  Garfield,  close  northeast  of  Hatton,  the  crest  of 
the  beach  is  1,078  feet  above  the  sea,  with  descent  of  6  or  7  feet  in  15  rods 
east  and  2  to  3  feet  in  10  rods  west.  In  the  west  part  of  section  15,  Wash- 
ington, the  beach  has  an  elevation  1,083  feet,  from  wliich  its  eastern  slope 
falls  5  feet  in  20  rods,  and  its  western  slope  3  feet  to  a  slough  10  to  30  rods 
wide,  which  is  mown  for  hay.  The  material  of  the  beach  ridge  is  fine  sand. 
Three  to  4  miles  farther  north,  in  sections  33  and  29,  Pleasant  View,  the 
irregular  deposits  of  the  Norcross  beach  are  about  1,085  feet  above  the  sea. 
In  the  northwest  corner  of  this  township,  passing  through  sections  7  and  6, 
this  shore  has  a  finely  developed  beach  ridge  of  sand  and  gravel,  with  crest 
at  1,090  to  1,095  feet  above  the  sea. 

On  the  Devils  Lake  and  Great  Falls  line  of  the  Great  Northern  Rail- 
way two  Norcross  beaches  are  crossed,  about  3  and  3  J  miles  east  of 
Larimore,  with  their  crests  respectively  at  1,092  and  1,080  feet.  Tlu-ough 
the  next  4  miles  northward  these  beach  ridges  appear  to  have  lain  on 
opposite  sides  of  the  Turtle  River  and  of  its  North  Branch,  causing  these 


NORCROSS  BEACHES  IN  NORTH  DAKOTA.  391 

streams  to  take  their  southerly  course  instead  of  passing  eastward  in  the 
direction  of  the  slope  of  the  surface.  Originally  confined  between  the  low 
beach  ridges,  they  have  since  eroded  channels  50  to  75  feet  deep  in  the 
general  sheet  of  till.  In  section  29,  Hegton,  the  elevation  of  the  upper 
Norcross  beach,  lying  west  of  the  North  Branch,  is  1,106  feet.  Along  the 
next  2  miles  northward  in  sections  20  and  17  the  crest  of  this  beach  varies 
from  1,100  to  1,105  feet.  It  is  intersected  by  the  North  Branch  in  the 
southwest  quarter  of  section  20.  Remnants  of  the  lower  Norcross  beach  on 
the  east  side  of  this  stream  in  section  29  have  an  average  height  of  1,090 
feet,  above  which  they  are  partly  heaped  10  to  15  feet  in  dunes. 

The  Norcross  shore-line  runs  northward  through  the  east  part  of  Agnes 
and  Inkster  townships.  In  sections  11  and  2,  Agnes,  the  upper  beach,  a 
fine  ridg-e  of  gravel  and  sand,  passes  about  25  rods  west  of  Orr's  station,  on 
the  Park  River  and  Langdon  branch  of  the  Great  Northern  Railway.  Its 
crest  here  has  a  height  of  1,102  to  1,105  feet.  In  sections  23  and  14,  Ink- 
ster, about  a  mile  west  of  Inkster  village,  two  Norcross  beaches  are  dis- 
tinctly developed,  crossing  a  tract  of  gravel  and  sand.  The  crest  of  the 
western  ridge  is  at  1,092  to  1,097  feet  and  that  of  the  eastern  at  1,090  to 
1,092  feet.  Depressions  4  or  5  feet  deep  lie  on  the  west  side  of  each  of 
these  ridges,  which  are  about  50  rods  apart.  A  half  mile  and  1 4  miles  far- 
ther west,  two  other  well-marked  beach  ridges,  running  northward  parallel 
with  the  foregoing,  belong  to  the  lowest  part  of  the  Herman  series.  The 
crest  of  the  eastern  one  is  at  1,113  to  1,122  feet,  and  of  the  western  at 
1,127  to  1,130  feet.  It  is  to  be  remarked,  however,  that  the  Herman  and 
Norcross  series  of  beaches  here  lie  very  near  together,  being  less  distinctly 
separated  than  farther  south  and  in  general  on  most  other  parts  of  the 
borders  of  the  lake  area. 

In  the  east  edge  of  section  10,  Inkster,  on  the  north  side  of  the  Forest 
River,  the  upper  Norcross  beach  is  well  developed,  attaining  a  height  of 
1,100  to  1,102  feet.  About  3  miles  farther  northwest  it  crosses  the  south 
line  of  section  28,  Eden,  with  an  elevation  of  1,107  feet.  In  sections  5 
and  6  of  this  township  it  is  marked  only  by  a  slightly  more  rapid  descent 
of  the  eroded  surface  of  till,  which  is  strewn  with  frequent  bowlders. 
Through  Eden  and  the  next  15  miles  northward  to  the  vicinity  of  Edinburg, 


392  THE  GLACIAL  LAKE  AGASSIZ. 

the  Norcross  shores  on  the  eastern  side  of  "the  mountains"  he  mostly 
within  a  half  mile  to  1  mile  distant  from  the  highest  Herman  shore.  Upon 
this  somewhat  steep  slope,  intersected  by  numerous  ravines,  neither  the 
Herman  shores  nor  the  Norcross  shores  are  so  distinctly  traceable  as  usual, 
either  by  beach  deposits  or  by  lines  of  erosion. 

From  the  northern  end  of  "the  mountains,"  near  Edinburg,  the  Nor- 
cross shore-lines  run  north-northwestward,  passing  about  2  miles  east  of 
Gardar,  less  than  a  mile  west  of  the  little  village  of  Mountain,  and  about 
1^  miles  east  of  Young  post-office.  At  the  locality  last  named  the  upper 
Norcross  shore  lies  about  a  third  of  a  mile  east  of  the  lowest  Herman 
beach,  and  is  marked  by  a  ridge  of  gravel  and  sand  10  to  20  rods  wide, 
with  a  depression  of  1  to  4  feet  on  its  west  side  and  a  descent  of  about 
6  feet  in  a  few  rods  to  the  east.  Its  crest  has  an  elevation  of  1,143  to 
1,145  feet,  being  30  feet  lower  than  the  adjacent  Herman  ridge. 

The  outer  border  of  the  j^lateau  of  the  Pembina  delta,  forming  the 
"first  Pembina  Mountain,"  was  the  Norcross  shore  of  Lake  Agassiz.  After 
the  Herman  stages  of  this  lake  all  its  lower  levels  with  southward  outflow 
washed  the  front  of  the  Pembina  delta,  carrying  away  much  of  this  deposit 
southward  and  eastward,  and  producing  the  steep  escarpment,  mostly  100 
to  175  feet  high,  by  which  it  is  bounded  on  the  east. 

On  the  more  gradually  sloping  northern  edge  of  this  delta,  2  to  4  miles 
west  of  Walhalla,  a  beach  formed  during  the  lower  Norcross  stage  passes 
from  east-southeast  to  west-northwest.  In  the  north  half  of  section  23, 
township  163,  range  57,  where  its  ci'est  has  an  elevation  of  1,135  to  1,140 
feet,  it  is  a  broad,  low  ridge,  chiefly  of  sand,  with  fine  gravel,  containing 
pebbles  tip  to  1  or  2  inches  in  diameter.  Most  of  the  gravel  is  derived 
from  the  Cretaceous  shale  of  the  Pembina  Mountain,  but  a  part  is  of  lime- 
stone and  crystalline  Archean  rocks.  A  depression  of  5  or  6  feet,  15  to  20 
rods  wide,  lies  on  the  southern  side  of  the  beach,  away  from  the  lake;  and 
its  northern  side  falls  off"  into  the  lacustrine  area  with  a  gentle  slope. 

Two  miles  farther  northwest  the  Norcross  shore-lines,  with  the  entire 
Herman  series,  leaving  the  Pembina  delta,  sweep  into  the  great  Cretaceous 
escarpment  of  the  second  Pembina  Mountain,  with  which  they  coincide 
thi'ough  several  miles  northward,  crossing  the  international  boundary. 


NOECEOSS  BEACHES  IN  MANITOBA.  393 

WESTERN    NORCKOSS    SHORES    IN   MANITOBA. 
(plates  xxx-xxxiii.) 

Tlu'ough  tOAvnship  1,  range  5,  the  Norcross  shores  of  Lake  Agassiz  He 
on  the  escarpment  of  the  Pembina  Mountain,  and  the  first  observations  of 
their  beaches  were  in  sections  7,  18,  and  19,  township  2,  range  5,  where  the 
mountain  wall  is  reduced  to  a  gradual  ascent  in  the  vicinity  of  Mountain 
City  and  Thornhill.  About  a  half  mile  southeast  of  Mountain  City  the 
upper  Norcross  beach  is  well  displayed  at  John  Borthwick's  house,  which  is 
built  on  its  crest,  1,167  feet  above  the  sea,  in  the  southwest  corner  of  section 
19.  Digging  for  wells  here  shows  that  the  gravel  and  sand  of  the  beach 
extend  only  to  a  depth  of  6  or  8  feet,  there  resting  on  the  Fort  Pierre  shale. 
From  the  crest  of  this  beach  ridge  its  slopes  fall  8  or  10  feet  within  a  few 
rods  on  the  east  and  about  4  feet  on  the  west.  It  is  bordered  on  the  west 
at  this  locality  by  a  surface  strewn  with  very  abundant  bowlders  up  to  5 
feet  or  rarely  more  in  diameter,  nearly  all  being  Archean  granites,  with 
perhaps  a  third  of  1  per  cent  of  magnesian  limestone.  Generally,  how- 
ever, the  surface  in  this  vicinity  has  few  or  no  bowlders;  and  a  shallow 
depth  of  ordinary  till  or  of  lacustrine  deposits  overlies  the  Cretaceous  shale. 
The  second  Norcross  beach,  also  forming  a  distinct  ridge,  lies  a  third  of  a 
mile  farther  east,  with  its  crest  about  1,150  feet  above  the  sea.  A  large 
excavation  for  sand  to  be  used  in  plastering  has  been  made  in  this  ridge  in 
the  south  edffe  of  this  section  19.  A  mile  farther  south  John  W.  Stodders's 
house  is  built  on  it  at  an  elevation  of  1,148  feet.  His  well,  12  feet  deep, 
passes  through  gravel  and  sand,  11  feet,  and  then  enters  the  sliale,  the  top 
of  which,  to  a  depth  of  6  to  12  inches,  is  a  hard,  calcareous  layer,  including 
nodules  and  veins  of  calc  spar.  Pieces  of  the  hard  surface  of  this  layer 
tlii-own  out  of  the  well  were  plainly  marked  with  glacial  striae,.  The  con- 
tinuation of  these  beaches  is  traceable  through  the  next  7  miles  northward 
across  the  Southwestern  Branch  of  the  Canadian  Pacific  Railway,  passing 
about  3  miles  east  of  Thornhill  to  Bradshaw's  Creek,  beyond  which  to  near 
Treherne  they  again  coincide  with  the  Pembina  Mountain  escarpment. 

About  IJ  miles  east  of  the  Little  Boyne  River,  near  Treherne,  the 
Manitoba  and  Southwestern  Railway  cuts  the  upper  Norcross  beach  ridge, 


394  THE  GLACIAL  LAKE  AGASSIZ. 

the  crest  of  which  is  1,195  feet  above  the  sea,  with  a  descent  of  about  5 
feet  on  the  west  and  10  feet  on  tlie  east.  A  half  mile  farther  east  it  cuts 
the  lower  Norcross  beach,  with  its  crest  at  1,167  feet,  from  which  there  is  a 
descent  of  10  feet  to  the  west  and  15  feet  to  the  east.  This  beach  has  been 
extensively  excavated  for  ballast,  a  spur  track  being  run  along  its  course  a 
quarter  of  a  mile  northwestward  from  the  railway.  The  excavation,  vary- 
ing along  this  distance  from  6  to  8  rods  in  width  and  from  5  to  15  feet  in 
depth,  shows  that  the  ridge  is  composed  of  interbedded  sand  and  gravel, 
the  layers  of  sand  constituting  about  half  of  the  entire  deposit.  The 
gravel  layers  differ  in  coarseness  from  those  that  contain  no  pebbles  more 
than  1  or  2  inches  in  diameter  to  others  containing  waterworn  masses  of 
shale  a  foot  across  and  Archean  cobbles  6  inches  in  diameter.  By  esti- 
mate, nearly  nine-tenths  of  the  gravel  is  the  hard  Fort  Pierre  shale  which 
makes  up  the  principal  mass  of  the  Pembina  Mountain,  the  Tiger  Hills, 
and  Riding  Mountain,  this  shale  gravel  being  often  almost  unmixed  with 
other  material;  about  a  twentieth  part  consists  of  two  classes  of  limestones, 
derived  in  nearly  equal  proportions  from  the  yellowish-gray  arenaceous 
limestone  of  Niobrara  age,  plentifully  fossiliferous,  which  outcrops  lieneath 
this  shale  on  the  Bo;yme  and  Assiniboine  rivers,  and  from  the  Paleozoic 
limestones  of  the  flat  country  about  Lakes  Manitoba  and  Winnipeg;  and 
the  remaining  twentieth  is  from  the  Archean  rocks  that  lie  east  and  north 
of  Lake  Winnipeg.  Continuing  northwesterly  and  northerly,  this  massive 
beach  i-idge  crosses  sections  8  and  17  and  the  eastern  edge  of  section  19, 
township  8,  i-ange  9,  beyond  which  it  is  lost  sight  of  on  the  undulating  and 
partly  wind-blown  surface  of  the  Assiniboine  delta. 

The  next  definite  observations  of  the  Norcross  shores  of  this  lake  are 
near  Neepawa,  where  the  Manitoba  and  Northwestern  Railway,  a  half  mile 
west  of  this  station,  crosses  small  beach  ridges  referable  to  the  upper  Nor- 
cross stage,  with  their  crests  1,223  to  1,225  feet  above  the  sea.  Close  to 
the  west  is  an  eroded  escarpment  of  till  15  feet  high,  rising  from  1,225 
to  1,240  feet.  On  the  other  side  of  the  station,  between  a  half  mile  and 
1  mile  east  from  it,  the  railway  crosses  a  surface  of  wind-blown  sand  with 
hollows  2  to  4  feet  deep,  the  crests  of  its  low  dunes  being  at  1,193  to  1,192 
feet.     These  occupy  the  level  belonging  to  the  lower  Norcross  beach.     The 


NOECEOSS  BEACHES  IN  MANITOBA.  395 

bed  of  the  railway  here,  formed  of  the  sand  of  the  Assiniboine  delta, 
further  worn  and  redeposited  by  the  lake  waves,  proves  somewhat  msecure 
because  of  its  liability  to  be  channeled  by  the  wind.  The  road  leading 
northward  from  Neepawa  to  Eden  and  Riding  Mountain  runs  on  the  crest 
of  the  upper  Norcross  beach  ridge  through  the  east  part  of  sections  21  and 
28,  township  15,  range  15,  3  to  5  miles  north  of  the.railway,  its  crest  there 
having  a  nearly  constant  height  of  1,223  feet,  with  a  descent  of  5  or  6  feet 
from  it  to  the  east  and  half  as  much  to  the  west.  Thence  this  beach  ridgre 
continues  north-northeasterly  to  the  east  part  of  section  23,  township  16, 
range  15,  where  it  has  an  elevation  of  1,225  to  1,230  feet,  with  width  of 
about  30  rods  and  descent  of  10  to  15  feet  on  its  east  side.  It  next  runs 
north  or  slightly  west  of  north  to  Thunder  Creek,  in  the  south  part  of  town- 
ship 17,  beyond  which  its  course,  with  that  of  the  lower  Norcross  shore,  is 
along  the  steep  ascent  of  Riding  Mountain.  In  the  journey  from  Eden 
post-office  (southwest  quarter  of  section  22,  township  16,  range  15)  to 
Orange  Ridge  post-office  (northwest  quarter  of  section  32,  township  16, 
range  14)  a  nearly  flat  surface  of  till  with  frequent  bowlders  is  crossed 
upon  the  width  of  3  miles  between  this  lieach  and  the  upper  Campbell 
beach,  descending  in  that  distance  from  1,200  to  1,100  feet,  approximately. 
Bowlders  are  especially  abundant  within  the  first  mile  from  the  upper  Nor- 
cross beach,  whence  the  erosion  of  the  lake  bed  supplied  its  gravel  and 
sand.  This  even  tract  of  till  would  seem  most  favorable  for  the  accumula- 
tion of  the  beaches  belonging  to  stages  of  Lake  Agassiz  between  its  upper 
Norcross  and  upper  Campbell  levels;  but  no  beach  ridge  nor  other  deposit 
of  gravel  and  sand,  nor  line  of  erosion  which  sometimes  takes  the  place  of 
these  to  mark  a  shore-line,  was  seen  in  the  intervening  distance.  It  seems 
probable  that  not  far  south  and  north  from  this  route  of  obseiwatiou  the 
lower  Norcross  and  the  two  Tintah  beaches  will  be  found. 

My  study  of  the  beaches  of  Lake  Agassiz  mapped  by  Mr.  J.  B.  TyrrelP 
on  the  eastern  flanks  of  Riding-  and  Duck  mountains  leads  me  to  correlate 
the  two  highest  gravel  ridges  near  the  Valley  River,  having  elevations  of 
1,280  and  1,260  feet  above  the  sea,  with  the  upper  and  lower  Norcross 
beaches  traced  by  me  in  North  Dakota  and  southwestern  Manitoba.     The 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Eeport,  new  series,  Vol.  Ill,  for  1887-88,  Part  E. 


396  THE  GLACIAL  LAKE  AGASSIZ. 

ascent  of  these  beaches  in  the  70  miles  northward  from  the  latitude  of 
Gladstone  and  Neepawa  to  the  Valley  River  is  about  75  feet,  or  very 
closely  1  foot  per  mile,  being  slightly  more  than  from  the  international 
boundary  to  Neepawa. 

On  Shanty  Creek,  20  miles  farther  north,  these  beaches,  according  to 
Mr.  Tyi-rell,  are  1,365  and  1,319  feet  above  the  sea,  showing  the  very 
remarkable  northward  ascents,  respectively,  of  85  and  59  feet,  or  about  4 
and  3  feet  per  mile. 

Along  the  next  25  miles  north  to  the  Pine  River,  where,  according  to 
my  correlation,  the  upper  Norcross  beach  has  a  height  of  1,440  feet,^  its 
ascent  continues  at  the  rate  of  3  feet  per  mile.  This  is  the  highest  altitude 
at  which  any  beach  of  Lake  Agassiz  has  been  recorded.  Its  latitude  is 
51°  52"  north,  being  200  miles  north  of  the  international  boundary.  It  is 
422  miles  north  of  Lake  Traverse  and  the  mouth  of  Lake  Agassiz,  in  which 
distance  this  shore  has  a  total  ascent  of  about  400  feet. 

The  significance  of  the  more  rapid  northward  rise  of  these  shore-lines 
and  others  below  them  in  the  district  of  Riding  and  Duck  mountains  than 
along  all  the  portion  of  the  lake  border  explored  by  me  farther  south  has 
been  pai-tly  discussed  in  Chapter  V,  on  the  history  of  this  lake,  and  will  be 
again  considered  in  Chapter  IX,  on  the  changes  in  the  levels  of  its  beaches. 

BEACHES  OF  THE  TINTAH   STAGES. 

EASTERN   TINTAH    SHORES    FROM    LAKE    TRAVERSE   TO    TINTAH    AND    NORTHWARD 

IN    MINNESOTA. 

(PLATES   XXIII-XXVI.) 

The  plateau,  3  to  4  miles  across,  which  formed  an  island  in  Lake  Agas- 
siz, situated  between  Wheaton  and  the  Mustinka  River,  on  the  southeast, 
and  the  Bois  des  Sioux  River  and  White  Rock  station,  on  the  northwest,- 
rising  to  an  altitude  of  1,040  to  1,055  feet,  is  encircled  by  the  Herman, 
Norcross,  and  Tintah  shore-lines.  This  high  tract  has  a  base  of  till,  but 
the  plain  forming  its  top  consists,  to  a  depth  of  10  to  20  feet  or  more,  of 

'  St.ated  to  be  1,460  feet  by  Mr.  Tvirell,  in  the  Bulletin  of  the  Geological  Society  of  America, 
Vol.  I,  1890,  p.  406;  but  later  published  by  him  as  1,440  feet  in  the  Am.  Geologist,  Vol.  VIII,  p.  23, 
July.  1891. 


THE  TINTAH  BEACHES  IN  MINNESOTA.  397 

delta  sand  and  gravel,  brought  by  the  glacial  representative  of  the  Shey- 
enne  River,  apparently  at  the  time  of  formation  of  the  Dovre  moraine,  when 
the  retiring  ice-sheet  began  to  uncover  the  edge  of  the  area  of  Lake  Agassiz 
(p.  150).  Previous  to  the  lower  Tiiitah  stage  of  the  lake,  the  River  Warren, 
outflowing  by  two  broad  channels,  one  south  and  the  other  west  of  this 
plateau,  had  eroded  the  upper  portion  of  the  valleys,  respectively  2  and  4 
miles  wide,  which  are  occupied  by  the  Mustinka  and  the  Bois  des  Sioux. 
At  the  time  of  the  lower  Tiiitah  beach  and  during  the  later  Campbell  and 
McCauleyville  stages  the  River  Warren  outflowed  wholly  west  of  this 
tract,  completing  the  erosion  of  the  valley  of  the  Bois  des  Sioux  from 
White  Rock  south  to  Lake  Traverse,  where  it  now  contains  a  great  marsh 
with  numerous  permanent  areas  of  water  1  to  3  miles  in  length. 

In  the  south  half  of  section  2,  township  128,  range  47,  at  a  distance  of 
about  1^  miles  east  of  White  Rock,  the  upper  Tintali  shore  bears  a  welL 
defined  beach  ridge  of  sand  and  gravel,  lying  on  a  surface  of  till.  This 
ridge  is  15  to  20  rods  wide,  rising  3  feet  above  the  surface  on  each  side, 
with  its  crest  about  1,015  feet  above  the  sea.  Thence  it  was  traced  nearly 
4  miles  in  a  curving  course  to  the  northeast  and  east,  passing  through 
sections  31  and  32,  Taylor.  At  the  center  of  section  31,  Mr.  Da\dd  War- 
riner's  farm  buildings  are  situated  on  its  top,  which  has  a  height  of  5  to  8 
feet  above  the  surface  of  till  at  the  south  and  north.  His  well  shows  that 
the  beach  gravel  and  sand  reach  to  a  depth  of  10  feet.  In  this  vicinity  the 
beach  is  somewhat  irregular  in  its  development  and  varies  from  10  to  30 
rods  in  width.  Other  irregular  sand  and  gravel  deposits  belonging  to  this 
shore-line  were  found  extending  from  south  to  north  in  sections  21  and  16, 
Taylor,  lying  on  a  tract  of  till  slightly  elevated  above  long  sloughs  on  the 
sovith  and  east. 

Two  very  small  beach  ridges,  from  1  to  3  feet  high,  consisting  of  sand 
and  gravel  on  a  nearly  flat  surface  of  till,  are  crossed  by  the  Evansville 
and  Tintah  line  of  the  Great  Northern  Railway,  about  1^  miles  and  1  mile 
east  of  Tintah.^  The  heights  of  their  crests  are  respectively  1,010  and 
1,007  feet  above  the  sea.     On  the  Minneapolis  and  Pacific  Railway,  2  miles 

'A  Dakota  name  meaning  prairie  (A.  W.  Williamson  in  Thirteenth  Annual  Report,  Geol.  and 
Nat.  Hist.  Survey  of  Minnesota,  for  1884,  p.  110). 


398  THE  GLACIAL  LAKE  AGASSIZ. 

fartlier  north,  these  inconspicuous  beach  ridges  pass  abovit  1  mile  and  a  half 
mile  east  of  Nash,  their  elevations  being  1,012  and  1,010  feet.  One  to 
2  miles  onward,  in  sections  25  and  26,  Chami^ion,  both  ridges  are  somewhat 
more  distinctly  developed  at  1,012  and  1,008  feet,  each  being  3  to  4  feet 
high  above  the  till  on  each  side. 

Thence  northward  between  the  Rabbit  and  Red  Rivers  the  level  of 
these  beaches  was  carefully  followed  with  leveling  across  a  very  smooth 
and  flat  expanse  of  till;  but  no  distinct  shore  marks,  either  of  ridged  beach 
deposits  or  of  any  noticeable  erosion,  were  found.  The  shore  passes  almost 
due  north,  lying  from  a  half  mile  to  1  mile  west  of  the  east  side  of  Brad- 
ford, and  crosses  the  Red  River  in  the  southeast  part  of  township  132, 
range  45,  between  2  and  3  miles  above  its  most  southern  bend. 

Within  a  half  mile  to  IJ  miles  north  of  the  Red  River  two  Tintah 
beach  ridges  are  well  developed,  consisting  of  gravel  and  sand  which  lie 
on  till.  The  eastern  and  higher  ridge  in  the  northwest  quarter  of  section 
26  and  southwest  quarter  of  section  23,  township  132,  range  45,  vai-ies  in 
width  from  10  to  25  rods;  its  crest  is  1,019  to  1,023  feet  above  the  sea, 
and  both  its  eastern  and  western  slopes  fall  3  to  7  feet.  Thi-ee-quarters  of  a 
mile  to  the  west  the  crest  of  the  lower  ridge,  which  is  of  similar  size,  has 
a  height  of  1,012  to  1,015  feet.  Thi-ough  the  next  2  miles  these  beaches 
are  not  distinctly  traceable,  and  the  surface  consists  of  slightly  undulating 
till.  In  the  east  edge  of  section  4,  this  township,  the  upper  shore-line  again 
bears  a  conspicuous  gravel  ridge,  with  crest  at  1,020  to  1,022  feet,  from 
which  within  10  rods  there  is  a  descent  of  5  feet  eastward  and  6  to  8  feet 
westward. 

In  the  northeast  corner  of  section  28,  Andi-ea,  the  upper  Tintah  beach, 
a  typical  gravel  and  sand  ridge,  has  an  elevation  of  1,017  to  1,018  feet 
above  the  sea.  Along  the  next  2  miles  northward,  in  sections  21  and  16,  its 
crest  holds  a  nearly  uniform  height  of  1,017  to  1,019  feet,  being  3  to  4 
feet  above  the  hollow  east  of  the  beach,  and  6  to  7  feet  above  the  adjoining 
surface  on  the  west.  Tlu-ough  the  west  half  of  section  9  and  the  southwest 
quarter  of  section  4  this  beach  is  not  distinctly  a  ridge,  but  is  represented 
by  a  somewhat  broad  tract  of  gravel  and  sand.  In  the  east  edge  of  sec- 
tion 6,  Andrea,  about  a  mile  west  of  the  foregoing,  the  lower  Tintah  beach 


THE  TINTAH  BEACHES  IN  MINNESOTA.  399 

forms  a  massive  gravel  and  saud  ridge,  with  crest  at  1,015  to  1,017  feet, 
rising  10  feet  above  the  adjoining  area  of  till  on  each  side;  and  it  continues 
north  with  the  same  conspicuous  development  through  tlie  east  edge  of 
section  31  and  the  southeast  quarter  of  section  30,  Akron. 

Across  the  next  3  miles  both  these  beaches  fail,  and  the  surface  in  their 
course  is  nearly  flat  till,  with  a  thin  covering  of  lacustrine  silt,  which  is 
apparently  due  to  the  action  of  the  lake  during  the  deposition  of  the 
englacial  till  from  the  melting  and  receding  ice-sheet. 

Again,  the  upper  Tintah  beach  has  a  very  massive  and  higher  devel- 
opment in  the  southwest  corner  of  section  8,  Akron,  and  extends  with  a 
width  of"  30  to  40  rods  and  an  elevation  of  1,024  to  1,029  feet  above  the 
sea  along  the  east  side  of  sections  7  and  6,  the  top  of  its  ridge  coincid- 
ing' nearly  with  the  south-to-north  section  line.  Its  maximum  width  and 
height  are  attained  at  the  quarter-section  stake  between  sections  7  and  8. 
On  the  east  the  descent  from  its  crest  is  3  to  6  feet,  and  on  the  west  10  to 
15  feet  within  20  rods.  This  gravel  and  sand  beach  passes  onward,  less 
massive,  but  having  a  distinctly  ridged  form,  through  the  western  tier  of 
sections  in  Tanberg.  In  the  east  edge  of  sections  31  and  30  its  elevation 
is  approximately  1,028  feet.  In  section  19  it  is  offset  a  quarter  of  a  mile 
to  the  west,  and  thence  runs  nearly  due  north  3  miles,  being  lost  near  the 
center  of  section  6  in  a  marshy  tract. 

The  lower  Tintah  beach  also  forms  a  conspicuous  gravel  ridge,  nearly 
parallel  with  the  foregoing,  at  a  distance  of  1  mile  to  a  half  mile  west, 
beginning  in  the  northeast  quarter  of  section  12,  township  134,  range  46, 
and  running  slightly  west  of  north,  with  an  elevation  of  1,015  to  1^017  feet, 
about  3  miles  to  the  east  part  of  section  25,  Manston.  There  it  is  offset  a 
quarter  of  a  mile  to  the  east,  and  thence  runs  due  north  along  the  west  line 
of  Tanberg,  having  a  height  of  1,016  to  1,018  feet,  to  the  marshes  in  which, 
like  the  upper  Tintah  beach,  it  is  lost  near  the  northwest  corner  of  this 
township. 

Both  the  Tintah  beaches  were  next  identified  in  the  vicinity  of  Barnes- 
ville.  On  the  northern  border  of  a  bowlder-strewn  higher  tract  of  till  the 
upper  Tintah  shore-line  is  marked  in  the  south  part  of  section  36,  Barnes- 
ville,  at  a  distance  of  about  a  quarter  of  a  mile  east  of  the  railway  line  to 


400  THE  GLACIAL  LAKE  AGASSIZ. 

Breckeuridge,  by  a  sand  and  gi-avel  deposit  several  feet  deep,  which  runs 
from  west  to  east.  Thence  this  beach,  having-  a  height  of  1,030  to  1,035 
feet  above  the  sea,  curves  to  the  northeast  and  north,  passing  through  the 
city  of  Barnesville  not  far  east  of  the  railway  station,  and  onward  a  little 
east  of  north  to  section  7,  Humboldt,  where  it  bends  northwestward.  The 
lower  Tintah  beach  in  Barnesville  is  a  shallow,  slightly  ridged  tract  of 
gravel  and  sand,  resting  on  the  general  slope  of  till,  above  which  it  rises  1 
to  2  feet  on  the  east,  while  its  western  side  falls  10  or  15  feet  within  20  or 
25  rods.  It  lies  close  west  of  the  street  which,  runs  north  from  the  railway 
station  for  a  third  of  a  mile  to  the  bridge  crossing  the  Willow  River  (also 
called  Whiskey  Creek),  beyond  which  the  street  itself  occupies  the  beach. 
Its  height  in  the  city  is  1,015  to  1,018  feet.  This  shore,  mostly  marked 
by  a  well-defined  gravel  ridge,  runs  north  the  next  2  miles,  lying  in  the 
west  edge  of  sections  19  and  18,  Humboldt,  and  then  turns  to  the  north- 
northwest,  passing  through  sections  12  and  1,  Barnesville. 

Thence  northward  the  Tintah  shore-lines  in  Minnesota  have  been  traced 
in  only  a  few  localities.  Through  Clay  and  Norman  counties,  however,  to 
the  Sand  Hill  River,  their  position  is  shown  approximately  on  PI.  XXV, 
in  accordance  with  the  general  westward  slope  of  the  east  border  of  this 
lacustrine  area. 

As  already  noted  in  the  description  of  the  Norcross  shore-Unes  (p.  387), 
two  beaches  observed  on  the  western  margin  of  the  Sand  Hill  delta  deposit, 
at  the  heights  of  1,060  and  1,070  to  1,073  feet,  seem  referable  to  the  upper 
Tintah  stages  of  the  glacial  lake;  and  the  continuations  of  these  beaches 
are  crossed  by  the  Fosstou  Railway  line  at  the  elevations  of  1,062  and  1,069 
feet  above  the  sea.  Tlu-ee-fourths  of  a  mile  to  1  mile  west  of  these,  and 
at  a  distance  of  nearly  2  miles  east  of  Beuoit,  this  railway  intersects  two 
less  conspicuous  beach  ridges,  with  crests  at  1,047  and  1,044  feet,  which 
are  believed  to  mark  the  lower  Tintah  stages 

These  shore-lines  are  inconspicuous  on  the  St.  Hilaire  railway  branch, 
but  3  to  5  miles  northward  several  beach  ridges  were  noted  by  Mr.  E.  C. 
Davis  in  leveling  for  a  proposed  canal  from  the  Red  Lake  River  at  Crooks- 
ton  to  its  southward  bend  at  the  mouth  of  the  Thief  River.  A  gravel  ridge 
probably  belonging  to  the  lower  Tintah  level  of  Lake  Agassiz  lies  about 
3  miles  east  of  the  Black  River  and  has  an  elevation  of  1,050  feet.     The 


TINTAH  BEACHES  NEAR  EOSEAU  LAKE.  401 

upper  Tintah  shore  was  not  recognized,  but  three  gravel  ridges,  succes- 
sively crossed  at  2  miles,  2.}  miles,  and  4^^  miles  northeast  from  the  1,050- 
foot  beach,  with  their  crests  respectively  at  1,086,  1,088,  and  1,092  feet, 
appear  to  be  lower  Norcross  beaches. 

Farther  to  the  north  the  Campbell  shore-lines  are  the  highest  that  have 
been  observed  by  me  on  the  east  side  of  Lake  Agassiz;  but  information  from 
others  gives  approximately  the  course  of  the  Tintah  shores  to  the  interna- 
tional boundary  and  the  south  and  west  sides  of  the  Lake  of  the  Woods. 

According  to  Mr.  Charles  Hallock,  the  road  from  Stephen  to  Roseau 
Lake  runs  on  a  gravel  ridge,  apparently  one  of  the  Tintah  beaches,  in  town- 
ships 159  and  160,  range  45,  passing  close  along  the  northwest  side  of  two 
lakes  Crossing  the  South  Fork  of  Two  Rivers  about  2  miles  northeast  of 
these  lakes,  the  road  is  described  as  continuing  for  the  next  15  miles  upon 
this  beach  ridge  or  another  closely  associated  with  it,  lying  5  to  8  miles 
southeast  of  the  Great  Roseau  Swamp  The  beach  forms  a  massive, 
smoothly  rounded  ridge  of  sand  and  gravel,  with  pebbles  and  cobbles  up 
to  4  inches  or  more  in  diameter.  Its  width  is  20  to  40  rods,  with  crest  5  to 
10  feet  above  the  adjoining  surface  of  till,  and  it  is  in  many  places  bordered 
on  the  side  that  was  away  from  the  lake  by  narrow  swampy  tracts.  A  trail 
which  leaves  this  road  before  reaching  Roseau  Lake  and  passes  east  to  the 
Lake  of  the  Woods  at  the  mouth  of  War  Road  River  is  said  to  lie  for 
considerable  portions  of  its  extent  on  a  beach  ridge.  This  also  doubtless 
belongs  to  one  of  the  Tintah  stages,  and  is,  indeed,  quite  likely  the  direct 
continuation  of  the  beach  occupied  by  the  Roseau  road. 

Dr.  George  M.  Dawson  has  kindly  supplied  a  manuscript  profile  of  the 
international  boundary  from  the  Lake  of  the  Woods  to  the  Red  River,  as 
surveyed  by  the  British  Boundary  Conunission,  which  shows  four  low  ridges, 
probably  Tintah  beaches.  They  are  crossed  successively  at  12  miles,  22 
miles,  24  miles,  and  32  miles  west  of  the  Lake  of  the  Woods,  their  crests 
being,  in  the  same  order,  1,088  feet,  1,081  feet,  again  1,081  feet,  and  1,070 
feet  above  the  sea.  The  first  and  second  of  these  ridges  are  respectively 
about  5  miles  east  and  5  miles  west  of  the  crossing  of  the  North  Branch  of 
the  Roseau  River,  and  the  fourth  is  3  miles  west  of  Pine  River.  The  ele- 
vation of  the  Lake  of  the  Woods,  varying  at  its  stages  of  low  and  high 
MON  XXV 26 


402  THE  GLACIAL  LAKE  AGASSIZ. 

water  from  1,057  to  1,063  feet  above  the  sea,  shows  that  this  large  lake  was 
first  separated  from  the  dimiuishmg  expanse  of  the  glacial  Lake  Agassiz 
between  the  times  of  formation  of  the  Tiutah  and  Campbell  beaches. 

WESTERN    TINTAH    SHORES    IN    NORTH    DAKOTA. 
(plates  xxvii-xxx.) 

In  the  northeast  corner  of  South  Dakota,  two  beach  ridges,  belonging 
to  the  upper  Tintah  shore  of  this  glacial  lake,  run  north-northwestward 
across  the  northeast  part  of  section  6,  township  128,  range  47.  The  east- 
em  ridge  is  20  to  30  rods  wide,  consisting  of  gravel  and  sand  on  the  west- 
wardly  ascending  surface  of  till.  It  has  a  height  of  1,014  to  1,018  feet 
above  the  sea,  with  a  descent  of  about  15  feet  on  the  east  and  of  3  to  6 
feet  on  the  west.  A  smaller  parallel  gravel  ridge,  rising  5  feet  from  its 
eastern  base  and  falling  1  to  3  feet  toward  the  west,  with  crest  at  1,015  to 
1,021  feet,  lies  a  quarter  of  a  mile  farther  west.  The  eastern  beach,  curving 
northwestward,  was  traced  several  miles  into  North  Dakota,  to  the  northeast 
quarter  of  section  22,  township  129,  range  48,  where  its  elevation  is  1,015 
to  1,018  feet.  Thence  it  is  probably  continuous  to  two  small  beach  ridges 
that  were  observed,  without  determination  of  their  height  (known,  however, 
to  be  approximately  1,015  feet),  in  or  near  the  north  edge  of  section  34, 
township  130,  range  49,  on  the  south  side  of  a  little  creek  which  there 
emerges  from  the  sand  area  of  the  Sheyenne  delta. 

The  Tintah  shore-lines  cross  the  eastern  portion  of  this  delta,  but  are 
seldom  ti-aceable,  even  on  its  smooth  areas,  and  still  less  among  its  frequent 
tracts  of  dunes.  The  altitudes  of  the  Northern  Pacific,  Fergus  Falls  and 
Black  HiUs  Railroad  show  that  they  cross  this  line  1  to  2  miles  east  of 
Barney.  Along  the  northern  border  of  the  delta  they  coincide  with  the 
escarpment  and  slope  descending  from  its  plateau,  which  pass  close  north 
of  Leonard  and  thence  extend  8  miles  westward  to  the  Maple  River.  On 
the  Fargo  and  Soiithwestern  Railroad  the  upper  Tintah  level  of  Lake 
Agassiz  eroded  an  escarpment  in  the  delta  sand  and  gravel  whose  top  has 
an  altitude  of  1,034  feet  above  the  sea;  and  the  lower  Tmtah  shore  bears 
three  beach  ridges,  5  to  7  feet  above  the  intervening  hollows,  with  their 
crests  at  1,017,  1,016,  and  1,014  feet. 


TINTAH  BEACHES  IN  NORTH  DAKOTA.  403 

Across  an  extent  of  nearly  60  miles  next  northward  we  have  only 
scanty  observations  of  the  Tintah  shores,  the  most  important  being  IJ 
miles  east  of  Clifford,  where  a  well-detined  gravel  ridge  upon  an  area  of 
till  was  seen  along  a  distance  of  2  miles  fi-om  south  to  north.  Its  crest  has 
an  elevation  of  1,040  to  1,045  feet  above  the  sea,  with  descent  of  a  few 
feet  on  its  west  side  and  of  15  to  25  feet  within  30  or  40  rods  eastward. 

From  the  South  Branch  of  the  Goose  River,  10  miles  north  of  Clifford, 
a  Tintah  shore-line,  marked  in  portions  of  its  course  by  an  eroded  slope 
and  in  other  portions  by  a  ridged  beach  deposit,  passes  to  the  north  and 
northeast  through  township  147,  range  53,  crossing  the  railway  line  from 
Portland  and  Mayville  to  Larimore  near  the  southwest  corner  of  sec- 
tion 2  and  the  North  Branch  of  Goose  River  near  the  center  of  this  section. 
Here  and  onward  to  the  north  through  tlie  eastern  tier  of  sections  in 
township  148,  range  53,  and  to  the  north-northwest  through  the  next  two 
townships  of  the  same  range,  and  onward  to  the  Devils  Lake  line  of  the 
Great  Northern  Railway  and  to  the  Turtle  River,  this  shore  lies  mostly  on 
the  eastern  slope  and  near  the  border  of  the  extensive  delta  of  sand  and 
fine  clayey  silt  brought  into  Lake  Agassiz  by  the  glacial  river  of  the  Elk 
Valley.  In  section  14,  Washington,  and  through  several  miles  northward, 
the  shore  bears  a  well-defined  beach  ridge,  which  in  the  southeast  quarter 
of  section  34,  Pleasant  View,  has  been  excavated  to  obtain  sand  for  plas- 
tering. In  portions  of  sections  8  and  5,  Pleasant  View,  and  in  section  31, 
Chester,  the  beach  deposit,  with  crest  at  1,050  to  1,055  feet  above  the  sea, 
changes  to  a  low,  eroded  escarpment  of  till  10  to  20  feet  high,  with  its  top 
5  to  15  feet  above  the  beach.  The  delta  here  extends  nearly  or  quite  to 
the  Tintah  shore,  which  divides  it  from  an  eroded  tract  of  till  on  the  east. 

North  of  the  Turtle  River,  which  is  crossed  by  this  shore-line  2  miles 
west  of  Arvilla,  it  continues  in  the  same  north-northwestward  course,  cross- 
ing an  area  of  till.  One  mile  east  of  Oit's  station  it  is  a  distinct  gravel 
and  sand  ridge,  and  about  three-quarters  of  a  mile  west  of  Inkster  it  has 
two  beach  ridges,  the  crest  of  the  western  one  being  1,070  to  1,072  feet 
above  the  sea,  and  that  of  the  lower  and  less  massive  eastern  ridge  1,060 
feet.  In  the  east  edge  of  section  28,  Eden,  the  Tintah  levels  of  Lake 
Agassiz  are  shown  by  erosion  upon  the  eastwardly  sinking  till  slope.     The 


404  THE  GLACIAL  LAKE  AGASSIZ. 

upper  limit  of  the  steelier  eroded  belt  is  at  1,062  to  1,070  feet,  being  about 
20  feet  above  its  base.  Beyond  this  township,  northward  to  the  Pem- 
bina delta,  the  courses  of  the  Tintah  shores,  though  not  exactly  traced,  are 
known  very  nearly  from  the  rate  of  eastward  descent  of  the  land  and  from 
the  mapped  course  of  the  next  succeeding  Campbell  beach.  At  one  locality 
a  Tintah  beach  ridge  was  noted,  near  the  middle  of  the  line  between  sec- 
tions 19  and  18,  Kensington,  about  2  miles  northwest  from  the  town  of  Park 
River;  but  the  next  two  miles  or  more  northward  have  a  rather  irregularly 
rolling  surface,  with  no  definite  beach  observable. 

The  Tintah  shores  are  only  a  short  distance  below  those  of  the  Nor- 
cross  stages  on  the  flanks  of  the  Pembina  delta  and  on  the  lower  part  of 
the  Pembina  Mountain  escarpment  for  several  miles  thence  northward. 

WESTERN    TINTAH    SHORES    IN    MANITOBA. 

(PLATES   XXX-XXXIII.) 

In  proceeding  northward  from  the  international  boundary,  the  Tintah 
beaches  were  first  observed  near  the  line  between  townships  1  and  2,  range 
5,  lying  on  a  terrace  which  forms  the  lower  part  of  the  Pembina  Mountain. 
On  the  boundary  this  terrace  is  about  three-fourths  of  a  mile  wide,  its 
eastern  margin  being  an  escarpment  that  rises  from  1,040  to  1,090  or  1,095 
feet;  and  from  its  verge  it  gradually  rises  25  to  35  feet  in  its  width,  so  that 
its  western  limit  at  the  base  of  the  main  escarpment  has  a  height  of  1,120 
to  1,125  feet.  Its  surface  is  till  with  plentiful  bowlders,  nearly  all  Archean, 
up  to  5  feet  m  diameter,  mostly  embedded  or  only  projecting  a  foot  or  less; 
but  the  slope  on  its  east  side  consists  of  weathering  and  pulverized  Cretace- 
ous shale,  which  is  thus  shown  to  form  the  principal  mass  of  the  terrace, 
beneath  a  thin  mantle  of  till.  In  the  distance  of  6  miles  northward  across 
township  1  this  terrace  widens  to  2  miles,  and  its  eastern  verge  sinks  to 
1,055  feet;  but  it  is  bordered  by  only  a  slight  escarpment,  about  15  feet 
high,  the  base  of  which  is  thus  at  the  same  level  as  on  the  international 
boundary.  In  its  width  of  2  miles  it  there  rises  about  90  feet  to  the  base 
of  the  mountain  escarpment,  at  1,140  to  1,150  feet.  A  quarter  to  a  third  of 
a  mile  east  of  this  escarpment  a  line  of  erosion  rises  from  1,110  to  1,125 
feet,  approximately,  marking  the  upper  Tintah  shore.      In  the  southeast 


TINTAH  BEACHES  IN  MANITOBA.  405 

quarter  of  section  5,  township  2,  this  shore  bears  scanty  deposits  of"  beach 
gravel  and  sand,  with  their  crest  at  1,110  to  1,115  feet.  The  lower  Tintah 
beach  lies  a  third  of  a  mile  farther  east,  and  is  a  distinct  ridge  of  gravel 
and  sand  with  its  crest  at  1,083  to  1,085  feet,  bordered  on  each  side  by  till, 
the  surface  of  whicli  is  5  feet  lower  on  the  east  and  3  feet  lower  on  the  west. 
Thomas  Kennedy's  well,  14  feet  deep,  in  the  northeast  quarter  of  section  5, 
township  2,  range  5,  found  the  till  only  4  feet  deep,  underlain  by  the  Fort 
Pierre  shale.  This  terrace  doubtless  owes  its  form,  like  the  far  more  prom- 
inent Pembina  Mountain,  to  preglacial  erosion  of  these  Cretaceous  beds. 
It  continues  along  the  foot  of  the  mountain,  with  a  width  of  1^  to  2  miles, 
at  least  to  the  South  Branch  of  Tobacco  Creek,  which  crosses  it  near  Miami 
post-office,  25  miles  north  of  the  international  boundary.  Throughout  its 
whole  extent  it  has  a  considerable  ascent  upon  its  width  from  east  to  west, 
as  in  the  localities  noted.  Much  of  its  surface  is  till  with  many  bowlders, 
but  some  portions  have  no  bowlders,  such  tracts  being  overspread  ^^'itll 
lacustrine  gravel  and  sand,  or  perhaps  occasionally  consisting  of  Cretaceous 
shale  next  below  the  soil,  with  no  drift  or  lacustrine  deposit. 

A  mile  west  of  Morden  the  escarpment  bordering  this  terrace  has  an 
ascent  of  about  40  feet,  with  its  top  approximately  1,070  feet  above  the 
sea.  Within  an  eighth  of  a  mile  to  the  west  is  the  lower  Tintah  beach,  a 
small  ridge  of  gravel  and  sand  which  has  been  excavated  for  use  in  plaster- 
ing, its  crest  being  at  1,085  feet,  nearly,  with  a  descent  of  5  or  6  feet  from 
it  to  the  east  and  2  or  3  feet  to  the  west.  It  extends  a  considerable  distance 
nearly  parallel  with  the  verge  of  the  terrace.  The  road  tlience  to  Thorn- 
hill  ascends  slowly  in  the  next  2  miles  across  a  somewhat  uneven  surface 
on  which  eight  or  ten  beach  ridges  are  discernible,  belonging  to  the  upper 
Tintah,  Norcross,  and  Herman  stages. 

The  most  remarkable  feature  of  this  tract  is  its  extraordinary  abun- 
dance of  bowlders,  nearly  all  Archeau,  usually  less  than  5  feet  in  diameter, 
but  in  many  places  ranging  in  size  to  10  feet  or  more.  Upon  an  area  that 
extends  at  least  1  to  2  miles  both  south  and  north  of  the  road  and  railway 
the  surface  is  as  thickly  strewn  with  bowlders  as  are  the  most  typical  ter- 
minal moraines  seen  by  me  in  Minnesota  and  South  and  North  Dakota. 
Many  of  these  rock  masses,  instead  of  being  embedded  in  the  drift,  as  is 


400  THE  GLACIAL  LAKE  AGASSIZ. 

generally  the  case  in  this  region,  project  2  to  3  or  4  feet  above  the  surface, 
or  lie  wholly  on  it  with  no  poi*tion  concealed.  Here  the  ice-sheet  probably 
terminated,  depositing  these  bowlders  in  the  west  margin  of  Lake  Agassiz, 
during  the  time  of  its  accumulation  of  the  tenninal  moraine  that  forms  the 
Avest  part  of  the  Tiger  Hills  and  the  Brandon  and  Arrow  hills. 

About  a  mile  south  and  west  of  Nelson,  the  lower  Tintah  beach  ridge, 
having-  an  elevation  of  1,085  feet,  apjjroximately,  lies  an  eighth  of  a  mile 
west  from  the  margin  of  the  terrace;  and  the  upper  Tintah  beach  probably 
extends  along  its  west  side,  close  to  the  base  of  the  Pembina  Mountain, 
where  the  elevation  is  about  1,100  to  1,120  feet.  The  width  of  the  terrace 
here  is  about  IJ  miles. 

A  half  mile  east  of  the  lower  Norcross  beach,  near  Treherne,  the 
upper  Tintah  shore  seems  to  be  indicated  where  it  crosses  the  railway  by 
a  line  of  erosion  in  the  Assiniboine  delta,  with  descent  approximately  from 
1,140  to  1,120  feet. 

On  the  profile  of  the  Manitoba  and  Northwestern  Railway  the  upper 
and  lower  Tintah  beaches  are  apparently  shown  about  3  miles  and  5J  miles 
east-northeast  of  Neepawa,  with  their  crests  respectively  at  1,158  feet  and 
in  two  ridges  at  1,116  and  1,111  feet  above  the  sea.  Witliiu  its  next  3 
miles  northward  the  upper  beach  is  represented  by  a  tract  of  low  dunes 
extending  through  the  east  edge  of  township  15,  range  15,  to  Snake  Creek. 
Thence  the  course  of  these  shore-lines,  as  shown  by  the  contour,  is  nearly 
due  north  to  the  foot  of  the  escarpment  of  Riding  Mountain,  in  township  1 7. 

Along  the  eastern  base  of  Duck  Mountain  the  Tintah  shores  of  Lake 
Agassiz  have  been  observed  by  Mr.  Tyrrell,  according  to  my  correlation  of 
the  beaches  shown  on  his  map  (see  p.  395),  as  follows:  The  upper  Tintah 
beach,  close  north  of  the  Valley  River,  at  an  elevation  of  1,220  feet  above 
the  sea;  both  the  upper  and  lower  Tintah  beaches  on  Shanty  Creek,  respec- 
tively, at  1,287  feet  and  1,235  feet;  and  the  upper  of  these  beaches,  extending 
several  miles  between  the  Pine  and  Duck  rivers,  at  1,365  feet.  In  propor- 
tion with  the  northward  ascent  of  the  upper  Tintah  beach  thus  indicated, 
its  height  on  the  Pine  River  would  be  about  1,335  feet,  and  on  the  Duck 
River,  a  dozen  miles  farther  north,  at  latitude  52°,  about  1,375  feet. 


THE  CAMPBELL  BEACHES.  407 

BEACHES    OF    THE    CAMPBELIj    STAGES. 

The  Campbell  shore-lines  have  in  general  somewhat  the  most  conspic- 
uous development  of  all  below  the  Herman  series.  They  belong  to  stages 
of  Lake  Agassiz  much  below  its  highest  level,  and  furnish  a  very  useful 
record  of  the  boundary  and  depth  of  this  body  of  water,  as  shown  on 
PI.  XXXIV,  near  the  time  when  it  ceased  to  outflow  to  the  south  at  Lake 
Traverse.  Considerable  portions  of  the  lower  and  principal  Campbell 
shore  are  marked  by  a  low,  eroded  escarpment  in  the  general  sheet  of  till; 
and  the  aggregate  length  of  such  terracing-  by  this  one  level  of  the  lake  is 
probably  eqiial  to  that  of  the  numerous  shorter  lines  of  escarpment  formed 
during  all  its  other  levels,  both  above  and  below.  Probably  the  land 
reposed  without  upward  movement  longer  at  this  stage  than  at  any  other 
in  the  history  of  the  lake,  unless  the  eai'liest  and  highest  stage  of  the  Her- 
man series  must  be  excepted.  It  is  also  to  be  remarked  that  no  other  shore 
of  Lake  Agassiz  bears  at  any  place  so  extensive  an  embankment  of  beach 
gravel  and  sand,  transported  a  long  distance  by  the  action  of  waves  and 
coastal  currents,  as  that  swept  southward  from  the  Pembina  delta  during 
the  Campbell  stages. 

Between  the  rate  of  northward  ascent  of  the  uppermost  Herman  beach 
and  that  of  the  Campbell  beach  there  is  a  remarkable  contrast.  Along  the 
300  miles  from  the  mouth  of  Lake  Agassiz  to  Gladstone  explored  by  me 
the  land  had  been  considerably  uplifted  after  the  formation  of  the  Herman 
beach;  but  its  level  in  all  this  extent  has  been  only  slightly  changed  since 
the  old  lake  shore  was  at  the  present  site  of  the  town  of  Campbell,  in  Min- 
nesota. Farther  to  the  north,  however,  on  the  east  side  of  Duck  Mountain, 
a  large  amount  of  differential  northward  uplifting  took  place  after  the 
Campbell  stages  of  the  lake.  The  rate  per  mile  of  northward  ascent  of 
the  Campbell  beaches  there  exceeds  that  of  the  first  and  highest  Herman 
beach  upon  all  the  country  south  of  Gladstone. 

Unusual  interest,  therefore,  appertains  to  the  Campbell  shores,  and  they 
have  been  more  fully  mapped,  especially  in  North  Dakota,  with  leveling  to 
ascertain  their  height  continuously,  than  any  other  of  the  successive  boun- 
daries of  this  glacial  lake,  whether  belonging  to  its  stages  of  southward  or 
of  northeastward  outflow,  excepting  only  the  Herman  beaches. 


408  THE  GLACIAL  LAKE  AGASSIZ. 

FROM    LAKE    TRAVERSE    AND    CAMPBELL    NORTH    TO    THE    TAMARACK    RIVER,    IN 

MINNESOTA. 

(PLATES   XXIII-XXVI.) 

For  a  distance  of  about  18  miles  north  from  the  mouth  of  Lake  Agassiz 
the  Campbell  shore-line  is  within  a  half  mile  to  1  mile  east  of  the  marsh 
with  lakelets  and  of  the  Bois  des  Sioux  River,  through  which  Lake  Trav- 
erse outflows.  Perhaps,  however,  it  would  be  better,  at  this  stage  of  the 
decrease  of  Lake  Agassiz  in  area  and  depth,  to  regard  its  mouth  and 
the  beginning  of  the  River  Warren  as  transferred  from  Lake  Traverse  12 
miles  north  to  the  vicinity  of  White  Rock. 

Parting  company  with  the  Bois  des  Sioux  5  or  6  miles  north  of  White 
Rock,  the  Campbell  shore  runs  northeastward  across  Campbell  Township, 
passing  less  than  a  mile  north  of  Tenney  station,  on  the  Minneapolis  and 
Pacific  Railway,  and  crossing  the  Breckenridge  line  of  the  Great  Northern 
.  Railway  at  Campbell.  Near  the  center  of  section  31,  Campbell,  it  is  recog- 
nized by  a  beach  ridge  which  has  been  excavated  for  masons'  sand.  On  the 
Minneapolis  and  Pacific  Railway  the  crests  of  its  scanty  gravel  and  sand 
deposits  are  980  to  983  feet  above  the  sea;  and  on  the  Aberdeen  Branch  of 
the  Great  Northern  Railway  the  top  of  the  beach  is  at  989  feet,  with 
adjoining  land  on  the  northwest  5  feet  lower.  The  vicinity  of  the  town  of 
Cam^ibell,  however,  has  no  definite  ridge.  A  half  mile  to  1  mile  north 
of  Campbell  the  beach  is  dimly  traceable,  with  crest  at  984  to  986  feet, 
rising  only  2  to  3  feet  above  the  general  surface;  and  it  has  the  same 
inconspicuous  development  in  its  course  thence  nearly  due  north  to  the 
Red  River. 

In  the  northeast  part  of  Richardson  this  shore  beai-s  a  well-defined 
ridge  of  gravel  and  sand,  which  runs  through  the  center  of  section  14  and 
the  east  part  of  sections  11  and  2.  It  has  been  excavated  in  the  southeast 
quarter  of  section  11,  showing  pebbles  up  to  IJ  inches  in  diameter.  The 
crest  of  the  beach  ranges  in  height  from  987  to  995  feet,  from  which  there 
is  commonly  a  descent  of  2  to  5  feet  on  the  east  and  twice  as  much  on  the 
west  to  the  general  siirface  of  till.  This  beach,  about  30  rods  Avide  and  5 
feet  high,  with  its  top  at  992  to  995  feet,  is  crossed  by  the  Northern  Pacific, 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.  XXXIV. 


MAP  OF  THK    SOl'THKHN    PORTION   OF  LMiK   AOASSIZ.  SlIOWIXC.  ITS   KXTKXT  IX  THK 

LOWFR   CAMPBELL   STAdK. 
Scale ,  about  42  miles  to  aiiiiidi. 


CAMPBELL  BEACHES  IN  MINNESOTA.  409 

Fergus  Falls  and  Black  Hills  Railroad  a  quarter  of  a  mile  west  of  Everdell 
station.  Thence  for  the  next  15  miles  its  course  is  a  few  degrees  west  of 
north  to  the  vicinity  of  Manston. 

Through  sections  15,  10,  and  3,  township  134,  range  46,  and  northward 
in  Manston,  the  Campbell  shore-line  is  mostly  marked  by  a  definite  gravel 
ridge,  the  land  on  each  side  being  till.  The  ridge  varies  in  elevation  from 
987  to  992  feet,  attaining  the  latter  height  1^  miles  southeast  of  the  village 
of  Manston,  where  it  rises  6  or  7  feet  from  its  east  base  and  has  a  descent  of 
about  10  feet  toward  the  west. 

In  Atherton  this  shore  is  intersected  three  times  by  the  railway  from 
Breckenridge  to  Barnesville.  A  beach  ridge,  for  the  greater  part  scantily 
and  irregularly  developed,  passes  northwestward  across  section  34  an-l  the 
railway.  Thence  curving  to  the  north  and  northeast,  it  lies  close  west  of 
the  railway  for  2  miles,  nearly  to  the  Deerhorn  Creek.  About  a  quarter 
of  a  mile  south  of  this  creek  it  again  crosses  the  railway,  from  which  a  spur 
track  turns  off  to  take  gravel  ballast  from  the  ridge,  its  excavation  being  6 
to  10  feet  deep.  For  the  next  2  miles  this  upper  Campbell  beach  runs 
nearly  parallel  with  the  railway  and  close  on  its  east  side  to  the  south  part 
of  section  10;  and  thence,  after  its  third  crossing  of  the  railway,  it  extends 
3  miles  nearly  due  north  to  a  cemetery  aboiit  1^  miles  west  of  Barnesville. 
The  elevation  of  the  beach  crest  in  sections  15,  10,  and  3,  Atherton,  and 
also  in  the  cemetery,  is  990  to  992  feet  above  the  sea,  with  a  descent  of  3 
or  4  feet  on  the  east  and  of  6  to  10  feet  on  the  west. 

A  second  beach  ridge,  of  smaller  size,  a  tenth  to  a  quarter  of  a  mile 
west  of  this,  with  its  crest  5  to  7  feet  lower,  about  985  feet,  begins  near 
Atherton  Station  and  is  continuous,  or  nearly  so,  through  section  15  and  the 
south  part  of  section  10.  The  foot  of  the  western  slope  of  the  lower  ridge, 
at  980  feet,  indicates  approximately  the  level  of  Lake  Agassiz  when  it  was 
formed.  A  slight  elevation  of  the  land,  probably  amounting  to  5  feet,  had 
apparently  taken  place  between  the  times  of  formation  of  these  two  beaches. 

Both  the  upper  and  the  lower  Campbell  beaches  are  also  well  exhibited 
2  to  3  miles  north  of  Barnesville,  near  the  railway  bridge  over  Siebers  Creek. 
In  the  northwest  corner  of  section  13,  Barnesville,  less  than  a  quarter  of  a 
mile  south  of  this  creek,  the  upper  beach,  forming  an  uTegular  belt  of 


410  THE  GLACIAL  LAKE  AGASSIZ, 

gravel  and  sand  from  992  to  980  feet  on  the  descending  slope  of  till,  is 
crossed  by  the  railway,  and  thence  runs  northward  as  a  more  definite  ridge, 
with  crest  at  992  to  995  feet,  through  the  west  half  of  section  12.  The  top 
of  the  lower  beach  ridge,  which  lies  an  eighth  of  a  mile  to  the  west,  run- 
ning nearl}-  along  the  west  line  of  this  section,  is  at  985  feet,  with  descent 
of  2  or  3  feet  eastward  and  about  10  feet  westward. 

Through  the  next  four  townships  to  the  north,  extending  24  miles,  the 
Campbell  shore-hnes  have  not  been  exactly  mapped,  but  their  position  is 
known  very  nearl}^  by  the  general  westward  descent  of  the  border  of  the 
lacustrine  area  toward  the  flat  Red  River  Valley  plain  which  forms  its  cen- 
tral part.  Near  the  middle  of  this  distance,  hoAvever,  on  the  Northern 
Pacific  Railroad,  two  beach  ridges,  belonging  to  the  Campbell  stages,  lie 
between  3  and  S^  miles  west  of  Muskoda.  The  railroad  profile  shows  that 
the  elevation  of  the  eastern  one  of  these  ridges  is  1,004  feet  above  the  sea, 
with  descent  of  4  feet  east  and  1 1  feet  west  in  its  width  of  30  rods,  and 
that  the  crest  of  the  second  ridge  is  at  1,000  feet,  7  feet  above  its  east  base, 
while  its  west  slope  falls  almost  20  feet,  the  whole  width  of  this  beach 
being  about  50  rods.  The  unusually  massive  development  of  the  Campbell 
beaches  here,  and  of  the  closely  associated  McCauleyville  beach,  is  due  to 
their  derivation  partly  from  the  delta  of  the  Buff'alo  River,  and  in  larger 
part  from  exceptional  erosion  in  the  slope  of  till  that  formed  the  lake  shore 
northward.  This  slope  is  strewn  with  many  bowlders,  the  remnants  from 
a  considerable  depth  of  till  worn  away  by  the  lake  waves. 

In  Hagen  the  Campbell  shore  is  mainly  traced  by  a  line  of  erosion 
forming  a  somewhat  steep  escarpment,  from  5  or  10  to  25  feet  in  height, 
near  the  foot  of  the  slope  of  till  which  thence  rises  gradually  toward  the 
east;  but  beach  gravel  and  sand  deposits  mark  its  course  where  it  crosses 
the  depression  occupied  by  the  South  Branch  of  the  Wild  Rice  River. 
Likewise  tlu-ough  Rockwell  this  lake  margin  is  an  eroded  till  escarpment. 

The  shore  again  bears  a  well-defined  gravel  ridge  in  Lake  Ida  Town- 
ship, passing  from  the  southeast  quarter  of  section  34  north-northeastward 
across  section  26  to  the  Wild  Rice  River,  and  thence  nearly  due  north 
through  the  west  edge  of  sections  13,  12,  and  1,  there  rising  6  to  8  feet 
from  its  eastern  base  and  descending  20  feet  toward  the  west.     The  height 


CAMPBELL  BEACHES  IN  MINNESOTA.  411 

above  the  sea  was  not  exactly  determined  here,  nor  along  the  next  12  miles 
of  this  shore  northward,  mostly  marked  by  a  low  escarpment  of  till,  in 
Green  Meadow  and  Spring  Creek  townships. 

Close  south  of  the  Sand  Hill  River,  in  section  34,  Liberty,  the  top  of 
this  Campbell  escarpment  is  1,010  feet  above  the  sea,  being  probably  10 
feet  higher  than  the  lake  level  when  it  was  made.  It  runs  in  a  neaidy 
due-north  course,  parallel  with  the  well-developed  McCauleyville  beaches 
which  lie  a  half  to  two-thirds  of  a  mile  farther  west.  Continuing  north- 
ward through  Liberty  and  Onstead  townships  and  the  southern  two-thirds 
of  Kretchmarville,  this  shore-line  is  almost  continuously  a  terrace  cut  in  the 
till,  having  a  descent  of  10  to  30  feet  within  as  many  rods.  Numerous 
residual  bowlders  are  strewn  upon  a  narrow  belt  below  the  terrace.  Ero- 
sion was  in  progress  along  the  greater  part  of  this  terrace  during  both  the 
upper  and  lower  Campbell  stages  of  the  lake;  but  a  beach  ridge  of  gravel 
and  sand,  which  was  accumulated  along  its  base  during  the  lower  stage, 
extends  through  section  5,  Onstead,  and  into  the  adjoining  sections. 

From  the  southeast  part  of  section  9,  Kretchmarville,  the  Campbell 
shore  takes  a  north-northeastward  course  for  the  next  10  miles  to  the  south- 
west corner  of  the  township  of  Red  Lake  Falls  and  to  the  Red  Lake  River 
Along  this  extent  it  bears  a  conspicuous  beach  deposit,  on  which  several 
farmhouses  are  built,  their  cellars  being  dug  to  the  depth  of  6  or  8  feet  in 
gravel  and  sand,  while  the  surface  on  each  side  of  the  shore-line  is  till.  For 
the  greater  part  of  this  distance  there  are  two  parallel  beach  ridges,  usually 
occupying  together  a  width  of  about  50  rods.  The  crest  of  the  eastern 
and  higher  beach  is  1,012  to  1,015  feet  above  the  sea,  and  that  of  the  lower 
beach  abovit  1,000  feet,  varying  from  this  only  1  or  2  feet.  Each  ridge  has 
a  descent  of  4  to  6  feet  toward  the  east,  and  their  western  bases  are  respec- 
tively at  995  and  985  feet,  approximately.  The  upper  and  lower  Campbell 
levels  of  Lake  Agassiz,  which  heaped  up  these  beaches  by  their  waves, 
were  very  nearly  at  1,000  and  990  feet. 

In  the  west  edge  of  section  30,  Red  Lake  Falls,  only  the  upper  beach 
ridge  is  present.  Its  width  is  about  30  rods,  and  its  elevation  varies  from 
1,013  to  1,020  feet,  with  descent  of  several  feet  eastward  and  15  to  20  feet 
to  its  western  base.     On  the  top  of  this  prominent  sand  and  gravel  ridge. 


412  THE  GLACIAL  LAKE  AGASSIZ. 

about  a  quarter  of  a  mile  south  from  the  Red  Lake  River  and  the  north- 
west corner  of  this  section,  he  five  dome-shaped  artificial  mounds,  of  grad- 
ually increasing  size  in  their  order  from  south  to  north.  The  southernmost 
is  about  30  feet  in  diameter  and  2  feet  high;  the  second  measures  50  feet 
across  and  is  3  feet  high;  the  third  is  slightly  larger,  with  a  height  of  4 
feet;  the  fourth  is  70  feet  in  diameter  and  rises  6  feet  above  the  beach;  and 
the  most  northern  has  a  diameter  of  80  feet  and  a  height  of  about  8  feet. 
These  mounds,  wliich  were  undoubtedly  used  for  bm-ial,  overlook  a  broad 
prospect,  especially  toward  the  west,  including  many  miles  of  the  well- 
wooded  river  valley. 

Tlie  St.  Hilaire  Branch  of  the  Great  Northern  Railway  crosses  the 
Campbell  beach  a  half  mile  east  of  Black  River,  the  crest  of  its  gravel 
ridge  being  1,019  feet  above  the  sea,  with  a  descent  of  6  feet  toward 
the  east  and  about  10  feet  westward.  Within  a  few  miles  farther  north  the 
line  of  the  survey  by  Mr.  Davis,  mentioned  on  page  400,  found  the  eleva- 
tion of  this  beach  1,022  feet,  from  which  its  slopes  fall  6  or  7  feet  on  each 
side.  Fai-ther  northward  its  elevation  has  not  been  determined,  but  its 
position  has  been  accurately  mapped.  In  townships  153,  Bray,  and  154, 
range  45,  it  iims  nearly  due  north  as  a  prominent  gi-avel  ridge,  passing 
close  west  of  the  centers  of  these  townships,  and  lying  from  2  miles  to  1 
mile  east  of  the  old  Pembina  trail,  which  follows  the  McCauleyville  beach. 
But  near  the  south  line  of  Viking  the  Campbell  beach  turns  slightly, 
thence  bearing  north-northwestward,  and  for  a  few  miles  in  the  central  and 
northwest  portions  of  Viking  the  trail  runs  on  its  top. 

Along  the  greater  part  of  its  explored  extent  north  of  the  Red  Lake 
River  this  shore  is  marked  by  a  single  large  gravel  ridge,  20  to  30  rods 
wide,  5  feet  or  more  above  the  adjoining  surface  of  till  on  the  east  and  10 
to  20  feet  above  its  western  edge;  but  in  the  northAvest  part  of  Viking  two 
Campbell  beaches,  a  quarter  to  a  half  mile  apart,  run  from  section  17  to 
section  6,  the  western  being  less  typically  ridged  and  mostly  10  to  15  feet 
lower  than  the  eastern.  On  the  top  of  the  western  beach,  near  the  middle 
of  the  west  half  of  section  6  and  a  quarter  of  a  mile  south  of  the  Snake 
River,  a  conspicuous  aboriginal  mound  was  noted,  having  a  diameter  of  50 
feet  and  a  height  of  6  feet.     Only  a  few  feet  south  from  its  edge  a  smaller 


CAMPBELL  BEACHES  IN  MINNESOTA.  413 

mound,  about  15  feet  in  diameter,  rises  1.]-  feet  above  the  beach.  •  No  other 
earthworks  were  seen  in  this  \acinity. 

Snake  River,  where  it  intersects  the  Campbell  and  McCauleyville 
beaches,  has  only  stagnant  pools  in  hollows  of  its  bed  during  dry  summers, 
while  the  Middle  and  Tamarack  rivers,  next  to  the  north,  seldom  or  never 
fail  to  carry  running  water,  although  reduced  nearly  to  the  size  of  brooks. 
Just  after  crossing  the  Snake  River  the  Pembina  trail  turns  westward  three- 
fourths  of  a  mile  to  the  McCauleyville  beach,  on  which  it  runs  nearly  all 
the  way  for  15  miles  northward.  The  Campbell  shore,  continuing  in  the 
line  of  its  western  beach  before  described,  passes  almost  due  north  along 
the  west  side  of  Marsh  Grove  Township,  and  thence  runs  a  little  to  the  west 
of  north,  bearing  a  fine  ridge  of  gravel  and  sand,  underlain  and  bordered 
on  each  side  by  till.  Its  distance  east  from  the  Pembina  trail  is  between  1 
and  2  miles,  to  the  Tamarack  River.  Beyond  this  stream  the  trail  turns  to 
the  northwest,  diverging  from  these  beaches,  which  continue  to  the  north 
and  north-northwest. 

Through  Marshall  County  the  Campbell  shore  lies  nearly  on  the  limits 
of  the  chiefly  prairie  country  on  the  west  and  of  the  wooded  region  on  the 
east.  The  beaches  are  mostly  grassed,  with  no  bushes  or  trees,  but  brush 
and  small  poplars  occupy  much  of  the  adjoining  land  on  the  west  and 
between  these  gravel  ridges,  and  almost  the  entire  area  on  the  east  bears 
a  small  growth  of  poplars,  where  they  have  not  been  lately  burned.  At 
a  distance  of  10  to  20  miles  eastward  a  forest  of  many  species  begins, 
comprising  the  common  poplar  or  aspen,  the  large-toothed  poplar,  the 
balsam  poplar,  cottonwood,  canoe  birch,  black  and  bur  oaks,  white  elm, 
white  and  black  ash,  red  and  sugar  maple,  basswood,  and  the  white,  red, 
and  jack  pines.  In  the  swamps,  and  frequently  on  higher  land,  tamarack, 
black  spruce,  and  balsam  fir  grow  in  abundance,  often  festooned  with 
moss.  Crossing  Kittson  County,  the  most  northwestern  in  Minnesota,  the 
Tintah  shore-lines  extend  here  and  there  into  heavily  timbered  tracts, 
while  the  Campbell  and  McCauleyville  beaches  continue  approximately 
along  the  somewhat  definite  boundary  dividing  the  woods  and  the  prairie. 


414  THE  GLACIAL  LAKE  AGASSIZ. 

CAMPBELL    SHORES    IN    NOKTH   DAKOTA 

(PLATES  XXVII-XXX.) 

Ou  the  west  side  of  Lake  Agassiz  one  of  the  Campbell  shore-lines 
begins  to  be  marked  by  a  beach  ridge  in  the  northwest  corner  of  section  5, 
township  128,  range  47,  Sonth  Dakota,  where  it  lies  about  15  rods  east  of 
L.  H.  Eldred's  house,  running  in  a  north-northwesterly  com-se  and  imme- 
diately passing  into  North  Dakota.  The  crest  of  this  gravel  ridge  is  988 
to  990  feet  above  the  sea,  with  slopes  that  fall  12  feet  to  the  east  and  3  to 
6  feet  to  the  west,  the  surface  on  each  side  being  till. 

The  Minneapolis  and  Pacific  Railway  and  the  Aberdeen  Branch  of  the 
Great  Noi-thern  Railway  cross  three  Campbell  beaches  west  of  the  Bois  des 
Sioux.  Wider  spaces  separate  the  shore-lines  here  than  elsewhere,  because 
the  land  is  very  nearly  level  and  the  lake  had  only  a  slight  depth  to  a  dis- 
tance of  several  miles  offshore.  When  the  district  was  uplifted  or  the  level 
of  the  water  fell  away  even  4  or  5  feet,  the  emerging  belt  varied  from  1 
to  3  miles  in  breadth.  The  most  eastern  of  these  beaches,  lying  Avitliin  a 
half  mile  east  of  Fairmouut,  forms  small,  irregular  ridges,  with  crests  at 

979  to  984  feet.  The  next,  passing  by  De  Villo  station,  has  an  elevation 
of  987  feet;  and  the  third,  which  is  the  continuation  of  the  ridge  at  Mr. 
Eldred's,  runs  northwestward  nearly  thi-ough  the  center  of  De  Villo  Town- 
ship, rising  5  feet  above  the  general  level,  with  its  crest  at  993  feet.  But 
probably  the  earliest  Campbell  stage  of  Lake  Agassiz  here  is  represented 
by  a  line  of  dunes  only  3  to  5  feet  in  height,  with  crests  at  995  to  997  feet, 
crossed  by  these  railways  about  2  miles  west  of  Oswald  and  Sonora.  The 
lake  levels  thus  indicated  range  from  992  feet,  very  nearly,  downward  to 

980  feet,  or  perhaps  2  or  3  feet  lower. 

Continuing  northwestward,  these  shores  converge,  on  account  of  the 
increasing  rate  of  westward  ascent  of  the  surface,  as  they  approach  the  Shey- 
enne  delta.  They  cross  the  Northern  Pacific,  Fergus  Falls  and  Black  Hills 
Raih'oad  on  the  very  gentle  southeastward  slope  of  the  delta  about  2  miles 
west  of  Mooreton,  but  are  not  definitely  traceable  there.  Eight  miles  far- 
ther north  the  Campbell  and  upper  McCauleyville  shores  begin  to  be 
marked  by  the  escarpment  or  steep  slope,  descending  eastward  20  to  50 
feet  within  about  a  mile,  which  forms  the  eastern  border  of  the  principal 


CAMPBELL  BEACHES  IN  NORTH  DAKOTA.         415 

plateau-like  mass  of  the  Sheyenne  delta,  having  been  sculptured  by  wave 
erosion  during  these  stages  of  the  glacial  lake.  The  same  shore-lines  con- 
tinue near  together  along  this  frontal  slope  through  a  distance  of  30  miles 
to  the  north  and  northwest,  passing  about  3  miles  west  of  Barrett,  1  to  2 
miles  west  of  Colfax,  a  similar  distance  southwest  of  Walcott,  about  3  miles 
southwest  of  Kindred,  and  1  to  1^  miles  north  of  Leonard.  In  many 
places,  however,  the  eroded  surface  as  it  was  shaped  by  the  lake  waves  has 
been  much  changed  since  by  the  winds,  which  have  heaped  up  its  sand  in 
dunes  10  to  30  feet  high. 

Beyond  the  northern  limit  of  the  Sheyenne  delta,  near  Leonard,  the 
border  of  the  lacustrine  area  rises  somewhat  steeply  from  the  Red  River 
Valley  plain,  and  the  lower  and  best-defined  Campbell  shore-lines  are 
mostly  united  or  lie  close  together,  whether  marked  by  beaches  or  by  an 
eroded  escarpment.  This  very  finely  developed  margin  of  the  old  glacial 
lake  has  been  mapped,  with  determination  of  its  height  by  leveling,  through 
all  the  distance  from  Leonard  to  the  international  boundary,  about  175 
miles. 

The  Fargo  and  Southwestern  Railroad  crosses  the  Campbell  shore 
close  below  the  Tintali  beaches  and  slightly  more  than  a  mile  northeast  of 
Leonard,  but  it  is  not  distinctly  marked  there,  lying  near  the  foot  of  the 
northeastwardly  declining  slope  of  the  Sheyenne  delta.  Its  course  is  thence 
west-northwest  about  8  miles,  crossing  the  Maple  River,  to  the  southeast 
part  of  section  29,  Walburg,  where  it  turns  to  the  north  and  holds  mainly 
a  north-northeast  course  through  the  next  25  miles  to  Wheatland  and 
Arthur.  About  a  quarter  of  a  mile  south  of  the  Maj^le  River  the  Camp- 
bell shore  is  marked  by  an  exceptionally  massive  beach  ridge  which  passes 
through  a  cemetery  in  the  north  part  of  section  3,  Watson,  its  crest  in  the 
cemetery  and  close  westward  behig  1,008  to  1,013  feet  above  the  sea  and 
some  75  feet  above  the  river.  This  ridge  consists  of  sand  and  fine  gravel, 
largely  derived  from  Cretaceous  shales,  with  no  pebbles  exceeding  2  inches 
in  diameter.  North  of  the  narrow  valley  cut  by  this  river  the  beach  ridge 
continues  with  an  elevation  of  1,006  to  1,009  feet  for  nearly  2  miles  to  its 
northward  bend,  beyond  which  the  shore  along  its  next  2  or  3  miles,  having 
left  the  tliinned  margin  of  the  delta  sand  brought  into  Lake  Agassiz  by  the 


416  THE  GLACIAL  LAKE  AGASSIZ. 

Sheyenne,  is  traced  as  a  low,  eroded  escarpment  of  till,  10  to  15  feet  in 
height,  with  base  at  995  feet. 

Four  to  6  miles  north  of  its  bend  the  Campbell  shore  is  compound 
and  irregularly  developed,  bearing  three  beach  ridges  of  gravel  and  sand, 
which  rise  5  to  10  feet  above  the  adjoining  surface  of  till  and  range  from 
986  to  1,000  feet  above  the  sea.  The  uppermost  forms  a  northwardly 
projecting  spit  in  the  southwest  quarter  of  section  4,  Walburg,  on  which 
Mr.  Luther  Wyckoff 's  well  found  sand  and  gravel  to  the  depth  of  10  feet 
and  till  beneath.  Along  its  course  of  6  miles  onward  to  Wheatland  some 
portions  of  this  shore  are  marked  by  beach  gravel,  with  crest  at  992  to  995 
feet;  but  commonly  there  is  no  beach  deposit,  its  place  being  occupied  by 
a  somewhat  steep  descent  toward  the  east,  falling  from  990  or  995  feet  to 
about  975  feet,  eroded  in  the  general  sheet  of  till.  Below  this  a  tract  a 
half  mile  or  more  in  width  is  fine  lacustrine  silt,  descending  eastward  with 
less  slope. 

In  the  east  part  of  Wheatland  village  the  Northern  Pacific  Raih-oad 
intersects  the  Campbell  beach  a  quarter  of  a  mile  from  the  station.  A 
massive  gi-avel  and  sand  ridge  here  occupies  a  width  of  about  60  rods, 
including  its  slopes,  and  rises  15  feet  above  the  nearly  level  expanse  thence 
eastward.  Its  crest,  at  994  feet,  is  10  feet  above  the  hollow,  40  rods  wide, 
on  its  west  side.  This  ridge  appears  to  have  been  formed  during  the  lower 
and  more  important  of  the  Campbell  stages  of  the  glacial  lake,  when  its 
level  was  about  990  to  985  feet.  The  accompanying  upper  shore-line, 
which  should  be  looked  for  10  to  15  feet  higher,  crosses  section  15  between 
2  and  3  miles  north  of  Wheatland,  where  Mr.  Joseph  Fuller's  house  is  built 
on  the  top  of  its  beach  ridge,  about  1,012  feet  above  the  sea.  His  well 
was  dug  15  feet  in  sand  and  gravel,  then  passing  into  till. 

North-northeastward  from  Wheatland  the  crest  of  the  lower  and  prin- 
cipal beach  holds  a  nearly  constant  elevation,  varying  in  the  first  3  miles, 
to  Swan  Creek,  from  993  to  996  feet,  with  descent  of  12  to  15  feet  in  20 
rods  east,  and  usually  3  to  5  feet  in  10  rods  west.  About  two-thirds  of  its 
gravel,  which  has  pebbles  and  cobbles  up  to  4  inches  in  diameter,  are  lime- 
stone; three-tenths,  by  estimate,  are  granite  and  other  crystalline  rocks; 
while  about  a  thirtieth  part  is  Cretaceous  shale.     Looking  east  from  this 


CAMPBELL  BEACHES  IN  ]SrOETH  DAKOTA.  417 

beach,  one  sees  a  very  flat  country,  originally  a  monotonous  prairie,  which 
is  in  view  to  a  distance  of  about  10  miles,  and  is  hidden  beyond  only  by 
the  curvatui'e  of  the  earth's  surface.  In  the  summer  nearly  all  this  expanse 
is  occupied  by  vast  fields  of  wheat  and  oats,  with  frequent  groups  of  sub- 
stantial farm  btiildings,  some  of  them  surrounded  by  trees.  The  thriving 
towns  of  Everest,  Casselton,  and  Amenia  are  seen  in  their  order  from  south 
to  north;  and  at  these  and  many  smaller  stations  of  both  the  Northern 
Pacific  and  Great  Northern  Railways,  also  on  some  of  the  large  farms, 
elevators  tower  above  the  flat  lands,  waiting  to  be  filled  with  their  grain. 
It  is  a  most  beautiful  prospect,  completely  characteristic  of  the  Red  River 
Valley. 

Through  the  next  5  miles  to  the  Rush  River  the  same  features  of  the 
beach  ridge  continue,  with  elevation  varying  from  990  to  996  feet,  except 
that  occasionally  the  gravel  and  sand  deposit  is  replaced  by  an  escarpment 
of  till,  with  crest  at  the  same  height  as  that  of  the  beach,  and  having  a 
steep  descent  of  10  to  15  feet  from  west  to  east.  For  nearly  4  miles  onward 
after  crossing  this  river  (a  puny  stream,  which  is  reduced  to  a  series  of 
stagnant  pools  during  summer  droughts)  the  Campbell  shore  is  a  till 
escarpment,  as  just  described.  Thence  tkrough  the  next  3  miles,  to  the 
town  of  Arthur,  it  is  again  a  massive  gravel  and  sand  ridge,  with  elevation 
of  994  to  998  feet.  Along  the  middle  part  of  this  distance,  in  section  32, 
Ai-thur,  the  descent  from  its  crest  westward,  away  from  the  lake  area,  is 
3  to  5  feet,  and  its  eastern  slope  falls.  10  to  15  feet  to  a  slough  or  moist 
tract,  wholly  mowing  laud,  beyond  which,  at  a  distance  of  an  eighth  to  a 
quarter  of  a  mile  from  this  beach,  there  is  a  lower  beach  ridge,  probably 
representing  the  highest  of  the  McCauleyville  stages,  with  crest  at  about 
985  feet. 

At  Arthur  the  Campbell  beach  curves  to  a  north  and  almost  uoitli- 
northwestward  course.  It  passes  about  an  eighth  of  a  mile  east  of  the  rail- 
way station,  where  its  elevation  is  994  to  997  feet  above  the  sea,  with  slopes 
descending  3  or  4  feet  to  the  west  and  about  10  feet  eastward.  Thence 
through  3  miles  north  the  top  of  this  gravel  ridge  varies  from  996  to 
1,002  feet.  For  the  next  20  miles  north-northwest,  crossing  the  South 
and  North  branches  of  the  Elm  River  (very  small  streams,  wholly  dry  or 
MON  XXV— — 27 


418  THE  GLACIAL  LAKE  AGASSIZ. 

chains  of  pools  in  summer),  the  Campbell  shore  is  almost  continuously  an 
escai-pment  of  till,  as  shown  by  fig.  7  on  page  26,  with  its  crest  and  the 
level  of  the  surface  westward  at  995  to  1,005  feet,  from  which  a  somewhat 
steep  slope  falls  10  to  20  feet  eastward.  It  passes  about  three-fourths  of 
a  mile  west  of  Hunter  and  2  miles  west  of  Greenfield.  Along  all  this 
distance  the  nearly  parallel  McCauleyville  shore,  20  to  30  feet  below  the 
top  of  the  Campbell  escarpment,  lies  about  a  mile,  or  in  part  only  a  half 
mile,  farther  east. 

From  a  mile  east  of  Roseville  the  Campbell  shore  runs  nearly  due  north 
4  miles  to  the  west  edge  of  the  town  of  Portland,  where  it  is  an  escarpment 
12  to  15  feet  high,  with  its  crest  and  base  respectively  about  1,000  feet 
and  985  feet  above  the  sea.  The  escaiiDment  is  eroded  in  the  southern 
extremity  of  the  sand  and  silt  delta  which  reaches  from  McCanna  to  Port- 
land, deposited  by  a  river  flowing  into  Lake  Agassiz  from  the  Elk  Valley 
while  lobes  of  the  melting  and  retreating  ice-sheet  lay  on  each  side.  For 
its  next  8  miles  this  shore-line  passes  northeastward  to  Morgan  Township, 
in  which  it  curves  to  the  north  and  north-northwest;  and  thence  it  holds 
the  latter  course,  with  only  deviations  of  a  few  degrees,  through  a  distance 
of  75  miles  north  to  the  Pembina  delta.  Between  Portland  and  Arvilla  it 
is  mostly  marked  by  a  well-defined  beach  ridge  of  gravel  and  sand,  lying 
on  till,  at  a  distance  of  2  to  3  miles  east  from  the  margin  of  the  delta,  which 
coincides  nearly  with  the  Tintah  shore-lines. 

The  Great  Northern  Railway  crosses  this  I'idge  three-fourths  of  a  mile 
east  of  Ai'villa,  where  it  occupies  a  width  of  about  60  rods.  Its  crest  has 
an  elevation  of  1,014  feet,  from  which  there  is  a  descent  of  23  feet  to  the 
east  and  9  feet  to  the  west.  Close  south  of  the  Turtle  River,  nearly  2  miles 
farther  north,  its  top  is  at  1,011  to  1,013  feet;  and  within  the  next  mile 
nortli  of  this  stream  its  elevation  is  1,007  to  1,010  feet.  In  the  vicinity  of 
Ai-villa  and  through  nearly  15  miles  onward,  passing  thi-ough  townships  152, 
Hegton,  and  153,  range  54,  both  the  Campbell  and  McCauleyville  shores 
bear  conspicuous  beach  ridges,  which  are  nearly  parallel  at  a  distance  of 
about  a  half  mile  apart. 

In  section  5,  township  153,  range  54,  and  for  6  miles  thence  northward 
in  Strabane  and  Inkster,  passing  a  third  of  a  mile  east  of  Inkster  station. 


CAMPBELL  SHORES  IN  NOETH  DAKOTA.  419 

the  Campbell  shore  is  a  low  escarpment  in  the  general  surface  of  till,  with 
crest  at  1,018  to  1,026  feet,  from  which  there  is  a  somewhat  steep  descent 
of  15  to  25  feet.  A  few  miles  farther  north,  however,  this  is  changed  to  a 
massive  beach  ridge  of  gravel  and  sand,  which  lies  about  a  half  mile  west 
of  Conway  station. 

Beyond  Conway,  along  a  distance  of  about  35  miles  of  very  direct 
north-northwest  course,  this  shore-line,  passing  tln-ough  the  west  edge  of 
the  town  of  Park  River  and  close  by  the  east  side  of  the  village  of  Moun- 
tain, is  almost  uninterruptedly  an  eroded  escarpment  of  till,  with  eastward 
descent  of  20  to  30  feet,  or  rarely  40  feet,  within  an  eighth  of  a  mile,  or 
often  a  less  distance.  At  Park  River  the  Campbell  escarpment  falls  rather 
abruptly  from  1,035  feet  to  1,015  feet  above  the  sea;  and  thence  a  gentle 
slope  of  till  sinks  about  15  feet  lower  in  a  half  mile  east  to  the  McCauley- 
ville  beach  and  railway  line.     In  the  northwest  comer  of  Dundee,  10  miles 

VV, 


•     o  .       f"_-    — 


FiQ.  17.— Profile  of  the  Campbell  escarpment  in  section  6,  Dundee.    Scale,  100  feet  to  an  inch. 

north  of  Park  River,  the  escarpment  falls  from  1,045  to  1,015  feet,  being 
steep  for  the  upper  half,  which  consists  of  till;  then  it  descends  more 
slowly  a  few  feet,  also  in  till,  with  frequent  bowlders;  and  its  lower  third 
is  a  somewhat  steep  slope  of  beach  sand  and  coarse  gravel  (fig.  17). 

From  its  foot  a  smoothed  surface  of  till  sinks  gradually  eastward, 
havinff  an  estimated  descent  of  100  feet  within  3  miles.  In  section  2, 
Gardar,  the  crest  of  the  escarpment,  at  1,045  feet,  bears  a  slight  ridge  of 
beach  gravel  and  sand,  2  to  3  feet  high  above  the  surface  of  till  on  the 
west;  but  the  face  of  the  escarpment,  here  falling  25  feet  within  30  rods  to 
the  east,  is  till  inclosing  plentiful  bowlders  of  granite  and  gneiss.  A  few 
miles  farther  north,  at  a  distance  of  about  1  mile  south  of  Mountain  village, 
the  steep  slope  falls  from  1,040  to  1,000  feet,  and  is  covered  with  a  beach 
deposit  of  gravel  and  sand  from  1,030  to  1,020  feet,  while  its  higher  portion 
and  a  broader  belt  forming  its  foot,  like  the  lower  land  extending  eastward, 


420  THE  GLACIAL  LAKE  AGASSIZ. 

are  till  (fig.  18).  At  Mountain  this  shore  descends  30  feet,  from  1,045  to 
1,015  feet,  within  a  distance  of  about  25  rods.  It  is  wholly  till,  with 
no  associated  beach  formation,  as  also  are  the  more  gentle  slopes  on 
both  sides,  sinking  toward  the  east  and  rising  westward.  During  all  the 
Campbell  stages  of  Lake  Agassiz  erosion  was  in  progress  iipon  this  long 
escarpment;  but  in  some  localities  the  action  of  the  waves  in  cutting  away 
and  removing  the  till  was  temporarily  changed,  alternating  with  accumula- 
tion of  shore  deposits  of  wave-brought  gravel  and  sand. 

Erosion  of  the  base  of  the  "first  Pembina  Mountain" — that  is,  the  front 
of  the  Pembina  delta,  along  a  distance  of  6  miles  to  the  southeast  from 
Walhalla — supplied  an  extraordinarily  massive  Campbell  beach  or  embank- 
ment, varying  from  a  quarter  of  a  mile  to  nearly  1  mile  in  width,  which 
extends  8  or  9  miles  in  a  curving  course,  convex  to  the  southeast,  through 
sections  5,  8,  17,  20,  29,  and  30,  township  161,  range  55,  and  the  south  half 


'W. 


Fig.  18.— Profile  of  the  Campbell  escarpment  1  mile  south  of  Mountain.    Scale,  100  feet  to  an  inch. 

of  section  25,  the  southeast  quarter  of  section  26,  and  the  west  half  of  sec- 
tion 35,  township  161,  range  56.  This  broad  belt  consists  of  gravel  and 
sand,  15  to  40  feet  or  more  in  depth,  which  were  cai'ried  southward  by  the 
shore  currents  of  Lake  Agassiz  in  its  Campbell  stages,  the  greater  portion 
being  transported  6  to  12  or  15  miles.  A  section  crossing  this  deposit  is 
shown  in  fig.  19.  The  crest  or  somewhat  plateau-like  top  of  the  embank- 
ment in  its  course  of  6  miles  south  of  the  Tongue  River  has  an  elevation 
of  1,020  to  1,030  feet  above  the  sea.  In  its  narrower  part,  north  of  this 
river,  its  crest  ranges  from  1,028  to  1,033  feet  along  the  first  mile  from 
the  river;  1,030  to  1,035  feet  along  the  next  mile;  and  1,(J35  to  1,045  feet, 
averaging  1,040  feet,  in  its  third  and  most  northern  mile,  passing  through 
the  southwest  edge  of  section  29,  township  162,  range  55,  where  it  becomes 
an  ordinary  beach  ridge  only  20  to  30  rods  wide,  with  descent  of  15  feet 
to  the  east  and  5  feet  to  the  west.     The  process  of  accumulation  of  the 


CAMPBELL  EMBANKMENT  AND  BEAOHES.  421 

extensive  embankment  was  by  transportation  of  its  material  along-  the  shore 
that  is  marked  by  this  beach  ridge,  and  by  building-  it  thence  out  into  the 
lake  in  this  long  hook  bent  to  the  west,  which  grew  gradually  in  length 
and  in  height  until  it  rose  to  the  lake  level,  its  growth  afterward  being  by 
additions  to  its  width.  From  its  eastern  verge  a  slope  of  the  same  gravel 
and  sand  falls  30  to  40  feet  in  a  third  or  half  of  a  mile,  to  a  south-to-north 
belt  of  dunes  and  sand  ridges,  10  to  15  feet  high,  which  appears  to  repre- 
sent the  McCauleyville  beaches.  West  of  this  embankment  a  basin  15  to 
40  feet  below  it,  mostly  consisting  of  fertile  wheat  land,  well  drained  by  the 
Tongue  River,  extends  6  miles  from  south  to  north,  with  a  maximum  width 
of  about  3  miles,  lying  between  the  embankment  and  the  southeastern  bor- 
der of  the  Pembina  delta,  which  was  the  lake  shore  during  the  Norcross 
and  Tintah  stages.     The  prevailing  course  of  the  coastal  currents  of  Lake 


97S. 


S^Bi^/v>rAi£/i/T  o^Saa/o  &  Fine  G/9AveL~ 


Fia.  19.— Section  across  the  Campbell  embankment  in  sections  20  and  21,  township  101,  range  55.     Horizontal  scale, 
one-third  of  a  mile  to  an  inch;  vertical  scale,  100  feet  to  an  inch. 

Agassiz,  and  of  the  transportation  of  its  beach  materid  here  and  elsewhere, 
on  both  its  western  and  eastern  sides,  was  from  north  to  south,  as  now  on 
Lake  Michigan,  due  then  and  now  to  the  prevailing  directions  of  the  winds, 
and  especially  of  gales  in  severe  storms,  when  the  broader  and  higher 
portions  of  the  beaches  were  chiefly  amassed. 

At  Walhalla  and  northwestward  the  Campbell  shore-lines  nin  alono- 
the  base  of  the  escarjiment  of  the  Pembina  delta,  where  its  steep  descent 
is  succeeded  by  a  more  gentle  slope.  Rev.  John  Scott's  house,  a  half  mile 
west  of  Walhalla,  and  the  houses  of  H.  A.  Mayo  and  John  Harvey,  respec- 
tively about  a  half  mile  and  2  miles  farther  northwest,  are  on  the  principal 
lower  Campbell  shore,  which  in  part  is  a  well-developed  beach  ridge,  with 
crest  1,030  to  1,035  feet  above  the  sea,  but  mostly  is  a  terrace  eroded  in 
the  delta  deposit,  falling  from  1,040  to  1,020  feet,  approximately.     In  the 


422  THE  GLACIAL  LAKE  AGASSIZ. 

northeast  part  of  section  14,  townshij)  163,  range  57,  about  3  miles  north- 
west of  Walhalla,  the  upper  Campljell  shores  form  such  a  teiTace,  which 
falls  from  1,075  to  1,035  feet;  while  a  more  moderate  slope  of  sand  and  fine 
gravel  below,  to  1,025  feet  at  the  road  running  northwest  from  Walhalla, 
jjrobably  represents  the  lower  Campbell  stage. 

Three  miles  farther  northwest  and  about  1  mile  south  of  the  interna- 
tional boundary  a  terrace  of  gravel  and  sand  in  the  west  part  of  section 
34,  township  164,  range  57,  marks  the  Campbell  levels  of  the  lake.  The 
front  of  the  terrace  rises  steeply  from  1,015  to  1,035  feet  above  the  sea, 
and  its  top  has  a  further  gentle  ascent  of  10  or  15  feet  in  its  width  of  about 
50  rods  to  where  it  abuts  on  the  base  of  the  lowest  escarpment  of  the  Pem- 
bina Mountain,  which  rises  from  1,050  to  1,100  feet.  From  the  top  of  this 
escarpment  a  terrace  or  plateau  of  till  and  iinderlpng  Cretaceous  shale 
extends  across  a  width  of  three-fourths  of  a  mile  west  to  the  principal 
Pembina  escarpment.  The  upper  Campbell  level  probably  passed  along 
the  top  of  the  sand  and  gravel  ten-ace,  near  the  elevation  of  1,045  feet;  the 
second  level  of  the  series  was  near  the  verge  of  this  terrace,  approximately 
1,035  feet;  and  the  third  and  lowest  stage  coincided  with  the  lowest  tliird 
of  its  steep  front. 

CAMPBELL    SHORES    IN   WESTEEN   MANITOBA. 

(PLATES   XXX-XXXIII.) 

Along  the  course  of  the  Cretaceous  terrace,  thinly  covered  with  till, 
which  borders  the  hase  of  the  Pembina  Mountain  for  at  least  25  miles 
northward  from  the  international  boundary,  as  described  in  connection  with 
the  Tintah  beaches,  the  upper  Campbell  shore-Hne,  there  having  an  eleva- 
tion of  1,045  to  1,050  feet,  coincides  generally  with  the  low  escarpment 
which  forms  the  east  margin  of  this  terrace.  A  portion  of  the  sculpturing 
of  this  escarpment  was  doubtless  done  by  the  waves  of  the  lake;  but  the 
main  outlines  of  the  terrace  as  a  bench  intermediate  between  the  expanse  of 
the  Red  River  Valley  and  the  high  Pembina  escarpment  seem  clearly  attrib- 
utable to  subaerial  erosion  before  the  Ice  age.  The  first  locality  where  I 
observed  a  distinct  beach  ridge  of  gravel  and  sand  referable  to  this  stage 
is  in  section  3,  township  4,  range  6,  a  half  mile  west  of  Nelson,  and  thence 


CAMPBELL  BEACHES  IN  MANITOBA.  423 

tlii'oug'h  a  distance  of  a  mile  or  more  north-northwestward.  It  lies  close 
east  of  the  teiTace  escai'pment,  and  has  an  estimated  elevation  at  its  crest 
of  1,055  feet.  In  township  7,  range  8,  this  shore  is  marked  by  a  conspicu- 
ous beach  ridge,  passing  through  sections  22,  27,  and  the  east  edge  of  33, 
lying  an  eighth  to  a  half  of  a  mile  west  of  the  Boyne  River,  with  its  crest 
about  1,055  to  1,060  feet  above  the  sea.  The  descent  from  the  crest  is  10 
to  15  feet  on  the  east  and  5  to  8  feet  on  the  west.  The  lake  at  this  stage, 
or  at  a  slightly  higher  level,  also  cut  an  escarpment  15  to  20  feet  high, 
with  its  top  at  1,075  feet,  appi'oximately,  which  passes  northwestward  across 
sections  28  and  29  of  this  township  and  northward  through  the  east  part 
of  sections  6  and  7,  township  8,  crossing  the  railway  about  7  miles  east  of 
Treherne. 

The  lower  Campbell  beach,  in  its  course  northward  from  the  interna- 
tional boundary,  lies  close  east  of  the  terrace  face  which  was  the  upper 
Campbell  shore.  In  sections  2  and  11,  township  1,  range  5,  the  elevation 
of  its  crest  is  1,036  to  1,040  feet.  On  the  west  a  nearly  level  surface 
extends  an  eighth  of  a  mile  to  the  terrace.  On  the  east  a  slope  of  beach 
gravel  and  sand  sinks  to  1,028  feet  in  about  25  rods;  and  a  similarly 
descending  surface  of  till  continues  to  1,015  feet  in  the  next  25  rods, 
beyond  which  there  is  a  much  slower  descent  eastward.  The  road  on  the 
line  between  townships  1  and  2,  range  5,  crosses  this  shore  about  three- 
eighths  of  a  mile  west  of  the  northeast  corner  of  section  34,  township  1, 
where  it  is  marked  by  a  typical  beach  ridge,  with  its  crest  at  1,034  feet, 
from  which  there  is  a  descent  of  10  feet  in  10  rods  to  the  east  and  3  or  4 
feet  in  10  rods  to  the  west.  This  ridge  was  seen  to  hold  nearly  the  same 
outline  and  height  through  a  distance  of  1  mile  or  more  to  the  south  and  a 
half  mile  north  to  a  small  creek.  About  a  half  mile  west  of  Morden,  where 
it  has  been  considerably  excavated  for  plastering  sand,  it  has  a  nearly  flat 
top  10  to  20  rods  wide,  with  ascent  on  this  width  from  1,030  to  1,040  feet, 
approximately,  resting  on  the  base  of  the  terrace  escarpment.  Five  to  6 
miles  farther  north  the  road  from  Nelson  to  Miami  runs  along  the  top  of 
this  beach  through  the  north  half  of  section  3  and  the  southwest  quarter 
of  section  10,  township  4,  range  6.  It  is  there  a  broad,  low  ridge  of  sand 
and  gravel,  20  to  30  rods  wide,  the  elevation  of  its  crest  being  about  1,035 


424  THE  GLACIAL  LAKE  AGASSIZ. 

feet,  or  10  feet  above  Nelson.     Continuing  northward,  it  crosses  the  north- 
east quarter  of  section  6,  township  5,  rang-e  6,  a  mile  west  of  Miami. 

The  course  of  these  shore-lines  was  not  traced  across  the  Assiniboine 
delta,  but  their  elevation  shows  that  they  lie  on  its  eastward  slope,  where 
they  are  intersected  by  numerous  ravines,  and  are  doubtless  obscured  in 
many  places  among-  its  dunes.  On  the  Canadian  Pacific  Railway  profile 
three  massive  beach  ridges,  the  two  higher  referable  to  the  upper  Campl^ell 
stage  and  the  third  to  the  lower  Campbell  stage  of  the  lake,  are  shown  3 
miles  to  2J  miles  west  of  Austin,  their  crests  being,  respectively,  1,087, 
1,081,  and  1,066  feet  above  the  sea.  These  beaches  are  each  about  30  rods 
wide,  with  descents  of  10  to  20  feet  from  their  crests  to  their  east  bases  and 
half  as  much  to  the  west. 

On  the  Manitoba  and  Northwestern  Railway  the  upper  Campbell  beach 
is  a  very  massive  rounded  ridge,  30  to  50  rods  wide,  along  whose  eastern 
slope  the  railway  runs  about  3  miles,  from  the  south  side  of  section  6, 
township  15,  range  13,  north-northwest  to  Arden.  Before  the  railway  was 
built,  the  old  trail  from  Winnipeg  to  the  Saskatchewan  River  passed  along 
the  top  of  this  ridge  the  same  distance  and  to  a  point  about  a  mile  north  of 
Arden,  there  leaving-  it  and  turning  to  the  west.  This  portion  of  the  trail 
was  a  good  dry  road  tlu-oughout  the  year,  being  thus  remarkably  contrasted 
with  the  deep  mud  along  most  of  its  extent  during  rainy  seasons.  Because 
of  this  character  of  the  road  and  the  beauty  of  the  smooth  beach,  which  is 
prairie,  without  tree  or  bush,  but  is  bordered  on  each  side  by  groves,  this 
avenue-like  tract  received  its  widely  known  name,  the  Beautiful  Plain.  It 
is  not  flat,  however,  as  the  name  seems  to  imply,  for  the  crest  of  the  beach 
ridge,  at  Arden,  1,090  feet  above  the  sea,  and  not  varying  more  than  a  few 
feet  above  or  below  this  elcA'ation  in  its  course  through  several  miles  south 
and  north,  is  15  to  25  feet  above  the  nearly  straight  margin  of  the  woods 
an  eighth  to  a  quarter  of  a  mile  east,  and  7  to  10  feet  above  the  more  irreg- 
ular margin  of  bushes  and  woods  on  the  west,  commonly  10  to  30  rods 
distant.  The  bai-rier  of  this  beach  ridge  was  sufficient  to  turn  the  White 
Mud  River  southward  3  miles  along  its  west  side.  Iii  a  section  cut  .6  feet 
deep  close  north  of  Arden,  for  the  passage  of  the  railway  and  in  excavation 
of  ballast,  the  material  of  this  beach  is  mainly  fine  gravel,  with  pebbles 


BEAUTIFUL  PLAIN  AND  ORANGE  RIDGE.  425 

only  a  quarter  to  a  tliird  of  an  inch  in  diameter,  but  also  includes  layers  of 
sand  and  coarser  gravel,  with  pebbles  up  to  2  inches  in  diameter,  of  which 
about  three-fourths  are  from  the  Paleozoic  formations  of  magnesian  lime- 
stone that  occupy  the  country  eastward  to  Lake  Winnipeg  and  northward 
to  the  Saskatchewan. 

From  Arden  this  beach  extends  north-northwest  through  the  northeast 
part  of  township  15  and  nearly  through  the  center  of  township  16,  range 
14.  In  the  north  half  of  township  16  it  has  in  several  places  a  naiTow, 
terrace-like  secondary  beach  on  its  eastern  slope  5  to  10  feet  below  the 
crest  of  the  main  beach;  and  it  is  closely  bordered  on  the  west  by  a  low 
escarpment  of  till  which  rises  5  to  10  feet  above  the  beach  ridge  and  forms 
the  margin  of  a  flat  or  slightly  uneven  expanse  of  till  that  ascends  slowly 
westward.  A  post-office  situated  close  west  of  this  beach  and  escarpment, 
in  section  32,  township  16,  is  named  Orange  Ridge,  in  allusion  to  the  orange- 
red  lilies  (Liliimi  pliiladelphicimi  L.)  which  grow  in  abundance  on  the  sandy 
and  gravelly  soil  of  the  beach.  The  elevation  of  the  Orange  Ridge  or 
Beautiful  Plain  beach  on  the  north  line  of  the  northeast  quarter  of  section 
32,  township  16,  is  approximately  1,080  feet  above  the  sea;  and  of  the 
escarpment  on  the  west,  which  was  eroded  dviriug  the  early  part  of  this 
upper  Campbell  stage,  1,090  feet. 

The  lower  Campbell  beach  is  crossed  by  the  railway  near  the  south- 
east corner  of  section  6,  township  15,  range  13,  where  the  elevation  of  its 
crest  is  1,061  feet,  with  a  descent  of  8  feet  in  about  15  rods  to  the  east  and 
5  feet  in  a  few  rods  to  the  west.  Through  the  next  15  miles  northward  it 
lies  a  half  to  two-thirds  of  a  mile  east  of  the  Beautiful  Plain  and  Orange 
Ridge.  East  of  the  latter,  on  the  line  between  townships  16  and  17,  range 
14,  the  elevation  of  its  crest  is  about  1,070  feet,  with  descent  of  15  feet  to 
the  east  and  10  feet  to  the  west. 

The  northward  continuations  of  the  Campbell  beaches  pass  through 
sections  5  and  8,  township  17,  range  14,  to  Thunder  Creek,  and  thence  a 
few  degrees  west  of  north  to  the  Big  Grass  River,  in  section  31  of  this 
township.  Thence  they  traverse  sections  6,  7,  and  18,  in  township  18, 
range  14,  and  the  northeast  part  of  township  18,  range  15,  where  a  swamp 


426  THE  GLACIAL  LAKE  AGASSIZ. 

on  the  west  about  2  miles  wide  separates  them  from  the  base  of  Ridiug 
Mountain. 

Mr.  TyiTell's  observations  and  map  of  the  beaches  of  Lake  Agassiz 
adjacent  to  the  northern  part  of  Riding  Mountain  and  on  the  eastern  and 
northern  sides  of  Duck  Mountain,  as  correlated  with  my  mapping  from 
Lake  Traverse  to  the  southern  end  of  Riding  Mountain,  show  the  principal 
Campbell  shore,  there  probably  the  upper  one,  to  be  marked  by  a  promi- 
nent gravel  ridge,  which  Mr.  Tyrrell  has  traced  through  distances  of  many 
miles.^  The  elevation  of  this  beach  ridge  where  it  crosses  the  Ochre  River, 
on  latitude  50°  56',  is  1,115  feet  above  the  sea.  On  the  Valley  River, 
about  30  miles  farther  northwest,  its  height  is  1,135  feet.  Twenty  miles 
thence  northward,  on  Shanty  Creek,  this  shore  has  two  beach  ridges, 
respectively  1,180  and  1,190  feet  above  the  sea.  The  lower  one  of  these 
beaches  has  been  followed  continuously  15  miles  to  the  north,  attain- 
ing there  an  elevation  of  1,225  feet.  Nearly  20  miles  farther  north,  the 
elevation  of  the  Campbell  beach  at  its  most  northern  observed  locality, 
on  latitude  52°,  is  1,290  feet,  perhaps  coiTesponding  to  its  upper  ridge  on 
Shanty  Creek. 

This  well-defined,  massive  gravel  ridge,  double  in  portions  of  its  course, 
is  doubtless  the  contini;ation  of  the  similar  beach  which  is  called  the  Beau- 
tiful Plain  and  Orange  Ridge,  ha^dng  at  Arden  an  elevation  of  1,090  feet 
above  the  sea.  For  the  distance  of  about  70  miles  north  from  Arden  to 
the  Ochre  and  Valley  rivers  its  ascent  continues  somewhat  as  froni  the 
international  boundary  to  Arden,  averaging  two-thirds  of  a  foot  per  mile. 
But  northward  from  Valley  River  to  Duck  River,  in  a  distance  of  about 
55  miles,  between  latitudes  51°  13'  and  52°,  this  beach  rises  146  feet,  or 
more  than  2^  feet  per  mile.  After  the  Campbell  stages  of  Lake  Agassiz, 
the  southern  part  of  the  lacustrine  area  was  only  slighth'  uplifted;  but  the 
region  of  Duck  Mountain  subsequently  experienced  a  greater  differential 
uplift,  increasing  in  amount  from  south  to  north,  than  that  of  the  earliest 
Herman  beach  farther  south,  where  nearly  all  of  its  inclination  had  taken 
place  before  the  Campbell  beaches  were  formed. 

'Pages  395  and  406,  this  chapter.  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new 
series,  Vol.  Ill,  for  1887-88,  Part  E ;  16  pages,  with  map.  Bulletin,  G.  S.  A.,  Vol.  I,  1890,  pp.  395-410. 
Am.  Geologist,  Vol.  VIII,  pp.  19-28,  July,  1891. 


THE  M'CAULEYYILLE  BEACHES.  427 

BEACHES  OF  THE  M'CAULBYVILLE  STAGES. 

The  channel  of  the  River  Warren,  outflowing  from  Lake  Agassiz,  had 
been  eroded  below  the  level  of  Lakes  Traverse  and  Big  Stone  when  the 
McCauleyville  beaches  began  to  be  accumulated.  Portions  of  the  bottom 
of  the  river-course  are  now  the  beds  of  these  lakes,  whose  maximum  depths 
are  reported  to  be  respectively  about  15  and  30  feet.  In  the  vicinity  of 
White  Rock  the  bottom  of  the  River  Warren,  eroded  in  till,  is  965  to  970 
feet  above  the  sea.  Along  the  broad  tract  of  marsh,  Avith  lakelets,  between 
White  Rock  and  Lake  Traverse,  the  depth  of  the  alluvial  swampy  deposit 
probably  ranges  from  10  to  15  feet,  reaching  down  to  the  level  of  the 
deepest  part  of  the  bed  of  Lake  Traverse,  approximately  955  feet  above 
the  sea.  This  or  a  slightly  greater  depth  of  the  channel  continued  between 
Lakes  Traverse  and  Big-  Stone,  where  alluvium  has  since  been  brought  in 
by  the  head  stream  of  the  Minnesota  River  to  tlie  depth  of  25  feet  or  more. 
The  bed  of  Big  Stone  Lake  sinks  to  about  935  feet  in  its  deepest  part,  and 
the  alluvium  of  the  Whetstone  River,  which  is  spread  along  the  Minnesota 
Valley  below  this  lake,  has  probably  a  corresponding  thickness  of  at  least 
30  feet. 

The  southern  portions  of  the  McCauleyville  shore-lines  of  Lake  Agassiz 
coincide  nearly  witli  the  levels  of  high  and  low  water  in  Lake  Traverse, 
which  are  approximately  976  and  970  feet  above  the  sea.  The  highest 
yearly  stage  of  the  glacial  lake  attended  the  more  rapid  melting  of  the  ice- 
sheet  in  summer,  while  its  Avinter  stages  doubtless  fluctuated  so  low  at 
times  as  to  reduce  the  depth  of  the  River  Warren  to  only  a  few  feet.  No 
appreciable  epeirogenic  movement  of  the  south  part  of  the  lacustrine  area 
appears  to  have  taken  place  during  the  time  of  formation  of  the  McCauley- 
ville beaches;  but  northward,  in  Manitoba,  the  earth's  crust  was  uplifted 
15  to  50  feet  within  this  time,  as  shown  by  its  upper  and  lower  shore-lines. 

Along  nearly  all  of  their  course  the  Campbell  and  McCauleyville 
shores  lie  nearly  parallel,  and  are  only  a  few  miles  or  mainly  less  than  1 
mile  apart,  permitting  both  to  be  mapped,  with  determination  of  their 
heights,  from  a  single  line  of  survey.  The  latter  are  10  to  20  or  30  feet 
below  the  former  in  their  southern  portion,  but  the  vertical  range  of  the 
two  series  increases  to  70  feet  in  southwestern  Manitoba,  while  the  highest 


428  THE  GLACIAL  LAKE  AGASSIZ. 

McCauleyville  lieacli  appears  to  lie  90  feet  below  the  highest  Campbell 
beach  at  the  northern  end  of  Duck  Mountain. 

The  McCaulej'^nlle  shores  are  seldom  marked  by  an  eroded  escarpment, 
like  that  which  characterizes  the  principal  Camjibell  shore  through  consid- 
erable distances.  Instead,  they  are  traced  by  beach  deposits,  which  are 
generally  well  defined  and  often  form  a  conspicuous  ridge,  vying  in  size 
with  au}'  other  beach  of  this  lake. 

EASTERN    m'cAULEYVILLE    SHORES    IN    MINNESOTA. 

(PLATES   XXIII-XXVI.) 

Through  a  distance  of  47  miles,  from  Lake  Traverse  north  to  the 
southern  edge  of  Mitchell,  a  few  miles  east  of  McCauleyville,  the  border 
of  Lake  Agassiz  at  its  lowest  level  of  southward  outflow  is  mapped  on  Pis. 
XXIII  and  XXIV,  the  line  being  drawn  on  the  second  of  these  plates  in 
accordance  with  the  elevations  determined  at  each  quarter-section  corner 
on  east-to-west  section  lines  by  the  Red  River  Valley  Drainage  Commission 
of  Minnesota  in  1886.  It  is  not  exactly  horizontal,  however,  but  has  a 
descent  from  the  known  level  of  the  lake  at  White  Rock,  about  970  feet 
above  the  sea,  to  the  level  indicated  by  the  beaches  between  j\IcCauleyville 
and  Barnesville,  which  is  approximately  960  feet.  Thus  there  appears  to 
have  been  a  slight  differential  northward  depression  of  this  area,  or  else  an 
increase  of  the  height  of  the  land  at  Lake  Traverse  as  compared  with  the 
country  northward,  since  Lake  Agassiz  ceased  to  outflow  to  the  south. 
These  changes  in  relative  elevations  were  opposite  to  those  which  were 
intermittently  in  progress  tlu'oughout  all  the  explored  portion  of  this  glacial 
lake  during  its  whole  history,  giving  to  the  shores  their  present  northward 
ascent.  But  the  discordant  movement  reached  no  farther  north,  for  beyond 
Barnesville  these  shores  on  both  sides  of  the  lake  rise  continuously,  though 
very  slowly,  from  1  inch  to  3  or  4  inches  per  mile,  to  the  international 
boundar}^. 

In  the  southwest  part  of  Mitchell  a  broad,  curved  embankment,  which 
may  be  called  a  hook,  extends  from  the  south  part,  of  section  21,  2  miles 
westward,  and  then  about  au  equal  distance  southward,  forming  a  plateau- 
like tract  a  quarter  of  a  mile  to  nearly  1  mile  wide.    The  narrowed  southern 


M'GAULEYVILLE  BEACHES  IN  MINNESOTA, 


429 


end  of  the  hook  lies  about  3  miles  east-northeast  of  McCauleyville.  It 
consists  of  gravel  and  sand  that  were  borne  from  northeast  to  southwest 
by  the  currents  and  waves  of  Lake  Agassiz  and  were  accumulated  in  this 
broad  deposit  as  a  curved  cape  of  its  shore,  which,  on  accQunt  of  the  prom- 
inence of  this  earliest  portion  observed  by  me,  has  been  named  tor  the 
neighboring  pretty  village  of  McCauleyville,  on  the  Red  River,  opposite  to 
Fort  Abercrombie.  The  elevation  of  its  top  is  960  to  970  feet  above  the 
sea,  being  5  to  10  feet  or  more  above  the  general  surface  of  till  on  the  east, 
while  westward  a  flat  plain  of  stratified  clay  and  tine  silt,  25  to  35  feet 
below  this  beach,  extends  3  miles  to  the  Red  River. 

Following  the  McCauleyville  shore  northeastward  8  miles  from  the  base 
of  this  hook  to  the  Deerhorn  Creek,  which  it  crosses  about  li  miles  south- 
west of  Atherton  station,  it  is  found  to  be  marked  chiefly  by  considerable 


1000 


Fig.  20. — Profile  across  beaches  at  and  near  Barneavillo,  Minn.     Horizontal  scale,  2J  miles  to  an  inch. 

erosion  of  the  till,  but  not  by  a  well-defined  escarpment.  At  only  two 
localities,  in  the  southwest  corner  of  section  11,  Mitchell,  and  again  in  the 
southwest  part  of  section  29,  Atherton,  short  and  inconspicuous  beach  ridges 
occur,  their  crests  being  in  each  place  965  feet  above  the  sea. 

Beyond  the  Deerhorn  Creek  the  course  of  this  shore  is  nearly  due 
north  for  the  next  10  miles,  lying  mostly  about  1  mile  west  of  the  Camp- 
bell beach.  It  runs  nearly  through  the  middle  of  section  4,  Atherton,  where 
a  small  beach  deposit  has  been  dug  for  masons'  sand;  and  in  Barnesville  it 
passes  2  miles  west  of  the  town.  Fig.  20  shows  a  profile  crossing  the  east- 
ern border  of  Lake  Agassiz  from  west  to  east  tlu-ough  Barnesville.  In  the 
southwest  part  of  section  2,  Barnesville,  it  forms  a  rather  broad  gravel  and 
sand  ridge,  rising  to  966  feet  above  the  sea,  with  springy  and  boggy  ground 
about  10  feet  lower  on  each  side. 


430  THE  GLACIAL  LAKE  AGASSIZ. 

One  to  4  miles  farther  uorth,  iu  sections  34,  27,  22,  21,  and  16,  Elkton, 
two  McCauleyville  beach  ridges  are  distinctly  developed,  extending  north- 
northwesterly  close  alongside  of  the  railway  that  runs  from  Barnesville  to 
Glyndon.  The  .upper  beach  has  an  elevation  at  its  crest  of  970  to  976 
feet  above  the  sea.  It  lies  about  an  eighth  of  a  mile  east  of  the  railway 
and  was  seen  to  be  continuous  at  least  3  miles,  attaining  its  most  massive 
development  and  maximum  height  near  Downer  station,  where  its  gravel, 
8  to  10  feet  in  depth,  has  been  largely  excavated  for  railway  ballast.  The 
lower  beach  is  smaller,  and  in  part  consists  of  a  belt  of  sand  and  gravel, 
lying  on  the  westwardly  descending  slope  of  till,  without  forming  a  definite 
ridge,  while  other  parts  are  ridged  up  1  to  2  feet  above  the  east  margin  of 
the  belt.  Its  gravel  contains  pebbles  and  cobbles  up  to  3  inches  in  diameter, 
and  the  depth  of  this  deposit  ranges  from  3  to  5  feet.  The  elevation  of  its 
top  is  964  to  966  feet,  and  its  western  base  at  960  feet  marks  approximately 
the  lake  level  when  this  second  beach  was  formed,  probably  8  or  10  feet 
lower  than  at  the  time  of  the  higher  beach. 

About  a  mile  north  of  Downer  these  shore-lines  turn  to  a  nearly  due- 
north  course,  leaving  this  line  of  the  Great  Northern  Railway.  On  the 
Northern  Pacific  Railroad  they  are  united  in  a  beach  ridge  that  is  crossed 
5  miles  east  of  Glyndon,  having  a  width  of  about  20  rods,  with  descent  of 
3  feet  to  the  east  and  10  feet  to  the  west  from  its  crest,  which  is  983  feet 
above  the  sea.  Thence  tln-ough  a  distance  of  about  20  miles  to  the  north 
the  McCauleyville  shore  is  not  exactly  traced,  but  is  known  to  he  close 
west  of  the  higher  shore-lines,  because  the  border  of  the  lacustrine  area 
rises  steeply  eastward. 

In  Rockwell  and  Lake  Ida  townships  a  well-marked  McCauleyville 
beach  ridge  of  gravel  and  sand,  with  till  on  each  side,  was  traced  several 
miles,  lying  about  a  half  mile  west  of  the  Campbell  escarpment  and  beach. 
Where  it  is  crossed  by  the  road  on  the  north  line  of  the  northwest  quarter 
of  section  26,  Lake  Ida,  its  width  is  about  30  rods,  and  its  east  and  west 
slopes  fall  respectively  about  5  and  15  feet,  its  crest  being  10  to  15  feet 
lower  than  that  of  the  similarly  massive  Campbell  ridge,  which  is  a  half 
mile  distant  to  the  east.  The  elevations  of  these  ridges  were  not  ascertained 
by  leveling,  but  are  probably  about  985  and  1,000  feet  above  the  sea. 


M'CAULEYVILLE  BEACHES  IN  MINNESOTA.  431 

My  next  observations  of  the  McCauleyville  beach  are  10  to  15  miles 
farther  north,  iu  the  townshij^s  of  Spring  Creek  and  Liberty.  A  large 
gravel  and  sand  ridge,  situated  about  two-thirds  of  a  mile  west  of  the 
Campbell  escarpment,  runs  from  south  to  north  along  the  east  edges  of 
sections  9  and  4,  Spring  Creek,  and  sections  33  and  28,  Liberty,  to  the 
Sand  Hill  River.  Mr.  Jacob  Stambaugh's  house  is  built  on  the  top  of  this 
beach,  in  the  northeast  corner  of  section  33 ;  and  two  aboriginal  mounds, 
each  about  3  feet  high,  were  noted  on  the  same  ridge,  one  close  north  and 
the  other  a  third  of  a  mile  south  of  this  house,  but  no  other  Indian  mounds 
are  known  in  the  vicinity. 

The  following  notes  of  elevations  describe  a  section  (fig.  21)  drawn 
from  east  to  west,  at  Mr.  Stambaugh's,  across  the  Campbell  and  McCauley- 
ville shore-lines.  From  the  crest  of  the  Campbell  escai-pment  of  till,  1,010 
feet  above  the  sea,  there  is  a  descent  westward  to  a  hollow  of  till  a  third 


c 

Zcimp6e/I  Escarpment                     El. 

AfPCsu/eyv/Z/e  Besc/res 

s^l^B 

lOOO 

V*'          -,— ~— *--^^  •:^-5ESr->^                                                     — 

r-oi~:-f  .^"i^Tlr.  -•  i^  »  ^-_-  r'-  -^o  ^T^.sl-L^T'Ai-' 

.950 

Fig.  21 Section  of  the  Campbell  and  McCauleyville  beaches  in  sections  33  and  34,  Liberty,  Minn.    Horizontal  scale 

one-fourth  mile  to  an  inch. 

of  a  mile  wide,  extending  from  south  to  north,  at  980  to  975  feet;  and 
west  of  this  the  McCauleyville  beach  ridge  rises  to  990  feet,  holding  tliis 
elevation,  within  1  or  2  feet  of  variation  above  or  below  it,  for  a  dis- 
tance of  at  least  2  miles.  Next  westward  the  beach  falls  about  15  feet 
within  20  rods,  and  bears  on  its  western  border  a  secondary  beach  ridge, 
which  in  its  most  definite  portions  rises  4  or  5  feet  from  the  east  and  falls 
about  10  feet  on  the  west.  The  western  base  of  this  lower  beach  ridge  is 
970  feet  above  the  sea,  which  represents  very  nearly  the  latest  McCauley- 
ville stage  of  Lake  Agassiz,  probably  10  to  12  feet  below  its  earlier  stage, 
when  the  higher  principal  beach  was  accumulated. 

For  nearly  25  miles  between  the  Sand  Hill  and  Red  Lake  rivers  the 
McCauleyville  shore  has  not  been  traced  on  the  ground,  but  it  is  mapped 
approximately  on  PI.  XXVI,  and  is  so  shown  by  fig.  22,  in  accordance 
with  the  known  westward  descent  of  the  surface.     It  lies  mostly  about  a 


432  THE  GLACIAL  LAKE  AGASSIZ, 

half  mile  west  of  the  Campbell  shore,  but  iu  the  viciuity  of  the  Red  Lake 
River  and  for  10  miles  northward  their  distance  apart  is  2  to  3  miles. 

The  Duluth  and  Manitoba  Railroad  crosses  two  McCauleyville  beach 
ridges,  and  runs  a  considerable  distance  on  the  eastern  one,  between  three- 
fourths  of  a  mile  and  2  miles  west  of  the  Black  River.  Then-  crests  are 
about  995  feet  and  990  feet  above  the  sea.  A  quarter  to  a  half  of  a  mile 
farther  north  the  St.  Hilaire  Branch  of  the  Great  Northern  Railway  crosses 
these  gravel  ridges,  Ives  station  being  on  the  course  of  the  western  ridge, 
into  which  the  railway  cuts  to  the  depth  of  a  few  feet.  The  crest  of  this 
beach,  which  was  followed  by  the  old  Pembina  trail,  is  at  990  feet;  and 
that  of  the  eastern  beach,  a  third  of  a  mile  distant,  is  at  997  feet.  Within 
a  mile  or  two  farther  north  the  profile  of  leveling  by  Mr.  E.  C.  Davis 


■1100 

loeo 

1900 

Fio.  22.— Profile  across  beaches  on  the  north  line  of  Onstead  and  Godfrey,  Minn.,  west  of  Maple  Lake.    Horizontal 
scale,  2^  miles  to  an  inch. 

(p.  400)  shows  the  McCauleyville  beach  at  996  feet.  In  this  vicinity  and 
along  the  next  15  miles  northward  this  beach  is  a  conspicuous  gravel 
and  sand  ridge,  mostly  20  to  30  rods  wide,  with  slopes  descending  5 
feet  or  more  to  the  east  and  10  or  15  feet  to  the  west.  Throughout  tliis 
distance  it  afforded  an  excellent  roadway  for  the  Pembina  trail,  on  which 
during  many  years,  until  about  1870,  long  processions  of  Red  River 
carts,  drawn  by  oxen,  traveled  from  St.  Paul  and  St.  Cloud  to  Fort  GaiTy 
(now  "Winnipeg),  carrying  provisions  and  supplies  for  the  Hudsons  Bay 
Company,  and  returned  laden  with  buffalo  skins  and  furs. 

Near  the  north  hue  of  section  20,  Numedal,  the  McCauleyville  beach 
ceases  for  the  next  few  miles  as  a  distinct  ridge,  and  the  Pembina  trail 
thence  passes  to  the  Campbell  beaches,  on  which  it  rims  through  Viking, 


EASTERN  M'CAULETVILLE  SHOEES.  433 

the  next  township  on  the  north.  From  the  ford  of  the  Snake  River  in  the 
northwest  corner  of  Viking  the  trail  deviates  tlu-ee-fourths  of  a  mile  to 
the.  west,  again  taking  its  way  along  the  crest  of  the  McCauleyville  ridge, 
which  is  finely  developed  through  the  next  18  miles,  to  the  north  part  of 
Nelson  Park  Township.  The  farther  course  of  this  beach,  however,  was 
not  followed,  as  it  extends  into  the  borders  of  a  more  wooded  or  bushy  and 
swampy  country. 

The  beach  is  intersected  by  the  Middle  and  Tamarack  rivers,  respec- 
tively, in  the  southern  and  northern  edges  of  township  157,  range  46, 
Wright.  Tlu'ough  the  south  half  of  Nelson  Park,  lying  next  north,  the 
conspicuous  beach  ridge,  rising  5  to  10  or  15  feet  above  the  originally 
unchanneled  surface  on  the  east,  was  a  sufficient  barrier  to  turn  the  Tama- 
rack River  from  its  normal  westward  course  to  one  a  little  east  of  south 
for  3  miles  before  it  cut  through  the  ridge.  At  the  center  of  the  township 
of  Nelson  Park,  where  this  river  first  comes  to  the  beach  from  the  east,  the 
Pembina  trail  departs  from  it  to  the  northwest.  In  its  extent  of  25  miles 
thence  to  Hallock,  descending  about  200  feet,  this  trail  crosses  several  shore- 
lines of  Lake  Agassiz  which  elsewhere  in  certain  portions  of  their  course 
are  very  clearly  defined;  but  no  distinct  beach  ridge  or  eroded  escarpment 
was  seen  on  the  trail  or  on  either  side,  although  the  surface  is  mostly  a 
gentle  and  regular  slope  of  till,  affording  apparently  very  favorable  condi- 
tions for  the  formation  of  shore  marks. 

Beyond  Nelson  Park  the  general  com'se  of  the  McCauleyville  shore 
across  Kittson  County  is  to  the  north  and  north-northwest.  It  appears  to 
be  represented  on  the  north  line  of  Minnesota,  according  to  the  profile  of 
the  British  Boundary  Commission  (p.  401),  by  a  massive  beach  ridge  with 
crest  1,016  feet  above  the  sea  and  20  feet  above  the  land  on  each  side, 
lying  20  miles  east  of  the  Red  River.  Within  a  short  distance  farther 
north,  in  Manitoba,  this  shore  probably  turns  east-southeastward  for  a 
dozen  miles  or  more,  to  cross  the  Roseau  River  near  Pointe  d'Orme  (Elm 
Point),  on  the  international  boundary.  Thence  it  passes  northward  and 
northeastward  tlu-ough  the  wooded  region  of  southeastern  Manitoba  to  the 
vicinity  of  Rennie  station,  on  the  Canadian  Pacific  Railway,  and  to  the 
Winnipeg  River,  which  it  crosses  not  far  above  the  mouth  of  the  English 
River. 

MON  XXV 28 


434  THE  GLACIAL  LAKE  AGASSIZ. 

WESTERN   m'cAULEYVILLE    SHORES    IN    NORTH    DAKOTA. 

(PLATES  XXVII-XXX.) 

My  most  southern  observations  of  the  McCauleyville  shore-hnes  in 
North  Dakota  are  on  the  latitude  of  Wahpeton  and  northward,  along  the 
eastern  border  of  the  Sheyenne  delta.  Two  levels  of  Lake  Agassiz  are 
indicated  by  the  beaches  and  escarpments  of  these  shores,  the  upper  being 
now  about  970  feet  and  the  lower  about  960  feet  above  the  sea.  A  beach 
ridge  formed  by  the  lake  at  the  upper  level  is  crossed  by  the  Northern 
Pacific,  Fergus  Falls  and  Black  Hills  Railroad,  about  a  third  of  a  mile 
west  of  Mooreton.  Its  width  is  about  30  rods,  and  the  elevation  of  its  crest 
is  974  feet,  with  descents  of  8  feet  to  the  east  and  3  feet  to  the  west.  This 
shore  continues  north  and  northwest  more  than  30  miles  along  the  base  of 
the  frontal  steep  slope  of  the  Sheyenne  delta,  the  erosion  of  which  was 
completed  by  the  lake  waves  during  this  stage.  With  the  Campbell  shores, 
which  also  run  along  this  border  of  the  delta  plateau,  it  passes  1  to  2  miles 
west  and  southwest  of  Barrett,  Colfax,  Walcott,  and  Kindi-ed,  and  about  1 J 
miles  north  of  Leonard. 

Sand  and  fine  silt  of  the  Sheyenne  delta,  however,  extend  to  a  distance 
of  several  miles  east  of  this  plateau,  partly  as  spread  originally  in  the  deep 
central  portion  of  the  lake  during  the  Herman  stages,  Avlien  the  delta  was 
formed,  and  partly  as  redeposited  from  the  erosion  of  the  delta  front  during 
the  later  and  lower  stages.  On  this  nearly  flat  tract  of  silt,  at  a  distance 
of  IJ  to  2  miles  from  the  plateau  front,  the  lower  McCauleyville  shore  is 
marked  by  a  beach  ridge,  which  through  most  of  its  observed  extent  of 
about  15  miles  has  become  a  narrow  belt  of  dunes,  occupying  a  width 
of  20  to  50  rods  and  rising  5  to  15  feet  above  the  general  level.  This 
belt,  running  from  south  to  north,  is  crossed  by  the  railway  2  J  miles  south 
of  Colfax,  Thence  it  gradually  curves  northwestward,  passing  about  a 
half  mile  east  of  Colfax  and  Walcott,  and  is  again  crossed  by  the  railway 
3  miles  northwest  of  Walcott.  The  land  on  each  side  of  the  beach  and  its 
dunes  has  an  elevation  of  955  to  960  feet,  which  represents  approximately 
the  former  water  surface. 

As  on  the  opposite  portion  of  the  east  side  of  the  lake,  this  latest  shore- 
line, formed  during  the  time  of  southward  outflow,  now  lies  about  10  feet 


M'CAULEYVILLE  SHORES  IN  NORTH  DAKOTA. 


435 


lower  here  than  the  present  height  of  the  Bois  des  Sionx  Valley  at  White 
Rock,  which  then  was  the  mouth  of  Lake  Agassiz.  The  northward  depres- 
sion of  the  intervening  area  or  its  southward  uplift,  inharmonious  with  the 
epeirogenic  movements  of  all  other  explored  parts  of  the  lake  basin,  was 


30<» 


/OO0-—.<^..^ 


Fig.  23. — Profile  acruaa  beachea  at  and  uear  Wheatland,  N.  Dak.    Horizontal  scaly,  2J  milya  to  au  inch. 


about  3  inches  per  mile  along  its  extent  of  40  miles,  taking  place  after  the 
flow  of  the  River  Warren  ceased. 

Northward  from  the  Sheyenne  delta,  the  McCauleyville  shore  tlii'ough 
the  next  30  miles  lies  within  a  mile,  or  mostly  a  half  mile  or  less,  to  the 
east  of  the  Campbell  shore,  both  passing  close  east  of  Wheatland  and 
Artluu'.  Fig.  23  presents  a  profile  crossing  the  western  beaches  of  Lake 
Agassiz  on  the  Northern  Pacific  Railroad  in  the  vicinity  of  Wheatland  and 
westward.  About  2  miles  south  of  Arthur  these  two  shore-lines,  each  there 
marked  by  a  beach  ridge,  are  only  an  eighth  to  a  quarter  of  a  mile  apart. 


f 


■  •..-■  -,ci-.-»j;. 


900 


^.■1  ILL ;.-  •.•■■----■.V-;  ■-.-.:,■  ci-'  ••  ??^^^=^rr3^ 


Tig.  24.— Profile  across  beaches  at  Hunter,  N.  Dak.,  and  westward.    Horizontal  scale,  2^  miles  to  an  inch. 

The  crest  of  the  lower  ridge,  which  probably  belongs  to  the  upper  McCau- 
leyville stage,  is  983  to  987  feet  above  the  sea.  Eight  miles  north  of  this 
locality,  the  McCauleyville  shore  at  Hunter  is  a  low,  eroded  escarpment  of 
till,  which  falls  from   980  to  965  feet,  passing  in  a  north-northwesterly 


436  THE  GLACIAL  LAKE  AGASSIZ. 

course  a  quarter  of  a  mile  east  of  the  railway  station  and  about  1  mile  east 
of  the  similarly  eroded  Campbell  shore.  Fig.  24  shows  the  westward 
ascent  of  the  border  of  the  lacustrine  area  in  the  vicinity  of  Hunter. 
Thence  these  shore-lines  extend  15  miles  north-northwest  and  6  miles  north 
to  Mayville  and  Portland,  holding  a  distance  of  about  1  mile  to  1^  miles 
apart. 

The  upper  McCauleyville  shore,  approximately  980  feet  above  the  sea, 
passes  about  a  mile  west  and  northwest  of  Mayville,  but  is  not  definitely 
marked  on  the  almost  level  surface  of  lacustrine  silt.  For  12  or  15  miles 
in  this  part  of  its  course,  from  6  miles  south  to  an  equal  distance  northeast 
of  Mayville,  the  lower  McCauleyville  shore,  on  account  of  the  very  slow 
descent  of  the  land,  lies  probably  2  or  3  miles  farther  east,  but  it  too  is 
only  dimly  traceable. 


/co<y 

9ee' 

FiQ.  25. — Profile  across  beacUea  iu  the  vicinity  of  Arvilla  aud  Lariuiore.  N.  Dak.    Horizontal  scale,  2J  miles  to  an  inch. 

Continuing  northward  to  the  vicinity  of  Arvilla,  the  upper  and  lower 
shore-lines  converge,  and  on  the  Great  Northei'n  Railway,  as  shown  on  fig. 
25,  they  together  form  a  massive  beach  ridge,  about  50  rods  wide,  with  its 
crest  991  feet  above  the  sea,  from  which  its  slopes  descend  18  feet  to  the 
east  and  8  feet  to  the  west.  This  ridge  lies  a  mile  east  of  Arvilla,  being 
about  a  third  of  a  mile  east  of  the  still  more  conspicuous  Campbell  beach. 

Beyond  Aiwilla  the  upper  and  principal  McCauleyville  shore  is  almost 
continuously  marked  by  a  fine  beach  ridge  of  gravel  and  sand,  5  to  10  feet 
above  the  adjoining  surface  of  till  on  the  west  and  east,  thi-ough  an  extent 
of  more  than  30  miles  to  Park  River.  In  section  14,  Hegton,  4  to  5  miles 
north  of  Arvilla,  the  crest  of  this  ridge  is  995  feet  above  the  sea,  and  other 
determinations  of  its  height  in  sections  27  and  16  of  the  next  township  on 


M'CAULEYVILLB  SHORES  IF  NORTH  DAKOTA. 


437 


the  north  were  990  to  995  feet.  In  the  southwest  part  of  Strabane,  passing 
about  a  mile  east  of  Inkster  (fig.  26),  its  elevation  is  mostly  995  to  998 
feet,  rising  5  to  8  feet  above  the  depression,  a  sixth  of  a  mile  wide,  in  the 
surface  of  till  on  its  west  or  landward  side,  while  its  lakeward  slope  falls 
10  to  15  feet. 


I 


IZOO 


I 

The  ffia/ge'an /s/and  of     lo 
A^orainic  Ti'/I        5 


■s. 

f 


so<^ 


Fig.  2C Protile  across  beaches  at  Inkster,  N.  Dak.,  and  (westward.    Horizontal  scale,  24  miles  to  an  inch. 

One  and  a  half  miles  north  of  Inkster  the  upper  McCauleyville  beach 
is  crossed  by  the  Langdon  Branch  of  the  Great  Northern  Railway  close 
south  of  its  bridge  over  the  Forest  River.  Its  crest  here  is  996  feet  above 
the  sea,  with  descents  of  8  feet  eastward  and  5  feet  westward.  Thence  it 
runs  close  along  the  west  side  of  the  railway  for  a  distance  of  about  8 
miles,  passing  an  eighth  of  a  mile  west  of  Conway  station.     Onward  for 


I 

t: 


1 
S    x; 


W. 


"r/ieA4e>unfaj/7s;'/s/an</^     g 
ofAlot-ainic  T///         vj     8 


I 


soo 

Fig.  27 — Profile  across  be.iclies  at  Park  River,  N.  Pak.,  and  westward.     Horizontal  scale,  2i  miles  to  an  inch. 

the  next  8  miles  to  Park  River  (fig.  27),  the  railway  is  built  on  the  top  of  the 
beach  ridge,  which  has  an  elevation  of  996  to  998  feet.  Thence  along 
the  distance  of  about  25  miles  to  the  Pembina  delta,  this  shore,  probably 
marked  throughout  by  a  deposit  of  gravel  and  sand,  lies  about  a  half  mile 
east  of  the  Campbell  escarpment. 


438  THE  GLACIAL  LAKE  AGASSIZ. 

A  belt  of  low  dunes  in  sections  28,  21,  and  16,  township  161,  range 
65,  running  along  the  eastern  base  of  the  great  Campbell  embankment 
that  was  built  out  to  the  soxith  from  the  front  of  the  Pembina  delta,  prob- 
ably records  the  McCauleyville  stages,' approximately  at  1,000  to  980  feet. 
North  of  the  Tongue  River  the  McCauleyville  shores  lie  a  third  to  a  half 
of  a  mile  east  of  the  Campbell  embankment  and  beach  ridge  along  a  dis- 
tance of  5  miles.  Thence  through  the  next  6  miles,  extending  northwest 
to  the  Pembina  River  and  Walhalla,  they  run  along  the  base  of  the  "first 
Pembina  Mountain,"  which  is  the  very  steep  ascent,  100  to  175  feet  high, 
of  the  eroded  east  border  of  the  Pembina  delta  plateau. 

The  road  from  Olga  to  Walhalla,  coming  down  from  this  plateau  about 
a  mile  southeast  of  the  Pembina  River,  crosses  at  its  foot  a  teiTace  of  sand 
and  gravel,  30  to  50  rods  wide,  having  an  elevation  of  1,000  to  1,004  feet 
above  the  sea,  which  was  formed  during  the  upjjer  McCaulej^ville  stage. 
The  highest  part  of  the  terrace  is  where  it  rests  against  the  "mountain," 
and  its  surface  descends  a  few  feet  to  its  northeastei'u  verge.  There  is 
next  a  somewhat  rapid  slope  to  985  feet  at  the  bottom  of  a  depression 
about  15  rods  wide,  beyond  which  the  road  passes  over  the  beautifully 
developed  lower  McCauleyville  beach.  This  ridge  is  20  to  30  rods  wide, 
with  smoothly  rounded  top  at  990  to  993  feet,  very  level  along  a  visible 
distance  of  a  third  of  a  mile  or  more  of  its  course  from  southeast  to  north- 
west, but  hidden  farther  away  by  trees  and  bushes  scattered  here  and  there 
on  its  otherwise  prairie  surface.  Its  lake  ward  northeastern  slope  falls 
about  20  feet  within  25  rods,  and  from  its  base  a  slower  descent  continues 
eastward. 

All  the  land  of  this  vicinity,  including  the  plateau  and  front  of  the 
delta,  the  terrace  and  beach  ridge,  the  intervening  hollow,  and  the  flat 
country  on  the  east,  consists  of  gravel,  sand,  and  fine  silt,  belonging  to  the 
delta  as  it  was  originally  deposited,  or  as  it  has  been  worked  over  by 
the  lake  waves  during  later  stages.  Indeed,  proceeding  eastward  30  miles 
to  the  Red  River  at  Pembina,  St.  Vincent,  and  Emerson,  one  crosses  only 
the  fine  silt  which  was  of  like  origin  with  the  delta,  but  was  carried  farther 
into  the  lake,  or  the  similar  alluvial  beds  that  have  been  laid  down  from 
floods  of  the  Pembina,  Tongue,  and  Red  rivers  since  Lake  Agassiz  was 
di-ained  away. 


WESTERN  M'OAULEYVILLE  SHORES. 


439 


Between  Walhalla  and  the  international  boundary  the  McCauleyville 
shore-lines  lie  on  the  western  margin  of  the  flat  expanse  that  stretches  from 
the  Red  River  to  the  Pembina  Mountain,  being  a  quarter  of  a  mile  to  1 
mile  east  of  the  first  conspicuous  westward  ascent,  as  shown  in  fig.  28.  In 
section  2,  township  163,  range  57,  about  2  miles  south  of  the  boundary, 
they  forin  a  tract  of  sand  and  fine  gravel,  40  to  50  rods  wide,  drier  than  the 
adjoining  surface  on  the  west  and  east,  passing  by  Elm  Point,  the  eastern 
limit  of  the  groves,  at  that  place  consisting  mostly  of  large  white  elms, 
which  extend  outward  from  the  wooded  Pembina  escarpment  along  springy 
water  courses  scarcely  depressed  below  the  general  surface.  The  elevation 
of  this  gravelly  tract  is  997  to  1,002  feet.  It  is  not  a  distinct  ridge  or  even 
swell,  and  is  recognizable  chiefly  by  the  contrast  of  its  comparative  dryness, 


Pembina  Mounfain 
'merrt 


SocA- 

Fig.  28. — Section  ou  the  international  boundary,  south  of  rangea  G  and  5,  Manitoba.     Horizontal  ac.ole,  2^  miles  to  an  inch. 

which  has  caused  it  to  be  selected  as  the  site  of  farmhouses.  The  adjoin- 
ing moist  and  springy  land  on  the  east  descends  15  or  20  feet  in  the  first 
third  of  a  mile ;  but  thence  the  surface  sinks  very  slowly  to  the  axial  lowest 
part  of  the  lake  basin  on  this  latitude,  at  the  Red  River,  its  gradients  in 
this  distance  being  gradually  diminished  from  15  feet  to  only  2  or  3  feet 
per  mile. 


WESTERN    M  CAULEYVILLE    SHORES    IN    MANITOBA. 

(PLATES    XXX-XXXIIl.) 

In  the  southwest  quarter  of  section  12,  townsliip  1,  range  5,  the  upper 
McCauleyville  shore  is  indicated  by  very  scanty  deposits  of  fine  gravel, 
1,006  to  1,007  feet  above  the  sea,  from  which  there  is  a  descent  of  3  or  4 
feet  in  20  rods  east.     Tlii-ough  the  east  half  of  section  23,  the  middle  of 


440  THE  GLACIAL  LAKE  AGASSIZ. 

section  26,  and  the  west  half  of  section  35  of  this  township,  two  McCau- 
leyville  beaches  are  developed  as  small  parallel  ridges  of  gravel  and  sand. 
The  upper  one  has  an  elevation  of  1,000  to  1,002  feet  at  its  crest,  from 
which  there  is  a  descent  of  1  to  2  feet  within  2  or  3  rods  to  the  west  and  5 
to  8  feet  in  10  or  12  rods  to  the  east.  Thence  a  nearly  level  surface  of  till 
with  frequent  bowlders  occupies  a  width  of  10  or  12  rods,  and  is  succeeded 
on  the  east  by  the  second  ridge,  the  western  slope  of  which  rises  2  or  3  feet 
to  its  crest.  This  is  about  5  feet  lower  than  the  upper  beach,  and  has  a 
similar  descent  of  5  feet  or  more  on  its  east  side. 

Fig.  29  presents  a  section  crossing  the  McCauley%'ille  and  higher 
beaches  on  the  latitude  of  Mountain  City,  where  the  Pembina  Mountain 
ascends  less  steeply  than  throughout  the  greater  part  of  its  extent. 

w. 

i5oot~C'^rnl>ina  Mounf-a.in 


Fig.  29. — Section  across  ranges  6  and  5,  Mauitoba,  9  to  10  miles  north  of  the  international  boundary.    Horizontal  scale, 
2J  miles  to  an  inch. 

About  a  quarter  of  a  mile  east  of  Nelson  the  upper  McCauleyville 
shore  is  a  line  of  erosion  with  a  descent  of  5  to  10  feet  within  a  short 
distance  from  west  to  east.  Four  miles  thence  to  the  north-northwest  it  is 
a  well-defined  beach  ridge  running  close  to  the  bridge  over  Boyds  Creek, 
near  the  northeast  corner  of  section  21,  township  4,  range  6;  and  it  con- 
tinues, but  is  less  conspicuous,  through  the  next  3  miles  northward  to  the 
church  in  the  northeast  corner  of  section  5,  township?  5,  range  6,  a  quarter 
of  a  mile  east  of  Miami  post-office.  Its  crest  at  Boyds  Creek  is  8  to 
10  feet,  and  at  Miami  5  feet,  above  the  more  massive  second  or  middle 
McCauleyville  beach,  which  lies  a  quarter  to  a  half  of  a  mile  farther  east, 
passing  north-northwesterly  through  the  west  edge  of  section  27,  and  the 
east  half  of  section  33,  township  4,  in  which  latter  it  is  offset  nearly  a 


M'CAULEYVILLE  SHOEES  IN  MANITOBA. 


441 


quarter  of  a  mile  to  the  east,  and  tlirough  the  middle  of  section  4  and  the 
west  half  of  section  9,  township  5. 

Three  McCauleyville  beach  ridges  are  crossed  by  the  Manitoba  and 
Northwestern  Railway  on  the  north  side  of  sections  32  and  33,  township 
14,  range  13,  about  4,  4^,  and  5  miles  southeast  of  Arden,  the  elevations 
of  their  crests  being  respectively  1,039,  1,029,  and  1,016  feet  above  the 
sea.  Each  of  these  rises  about  5  feet  above  the  surface  on  the  east.  They 
continue  as  prominent  gravel  ridges  north-northwestward  through  the  west 
half  of  township  15  and  the  southwest  part  of  township  Ifi,  range  13,  and 
through  the  northeast  part  of  township  16,  the  east  half  of  township  17, 
and  the  west  half  of  township  18,  range  14,  to  the  vicinity  of  PhilHps's 
ranch.  The  relationship  of  the  Campbell,  McCauleyville,  and  lower  beaches 
near  Arden  and  eastward  is  shown  in  fig.  30. 


5-8 


FlH.  30.— Section  on  the  south  side  of  townships  15,  ranges  13  and  12,  Manitoba,  between  Arden  and  Clailstone.     Hori 
zontal  scale,  2^  miles  to  an  inch. 

In  township  15,  range  13,  next  east  of  Arden,  the  most  western  and 
upper  one  of  the  McCauleyville  beaches  is  called  Lowdons  Ridge,  from 
Thomas  Lowdon,  whose  house,  the  first  built  on  it,  is  in  the  middle  of  the 
east  edge  of  section  30.  The  middle  beach  appears  to  be  twofold  in  sec- 
tions 20  and  29,  Joshua  Ritchie's  house  being  built  on  one  of  its  ridges  and 
the  Rose  schoolhouse,  a  quarter  of  a  mile  farther  east,  on  the  other.  About 
three-quarters  of  a  mile  east  of  the  Rose  Ridge  is  the  lower  McCauleyville 
beach,  on  which  the  trail  to  Lake  Dauphin  runs  northward  through  town- 
ships 15  and  16.  Lewis  McGhie's  house  is  built  on  the  eastern  slope  of 
this  beach,  in  the  northeast  quarter  of  section  28,  township  15.  Lowdon's, 
Ritchie's,  and  McGhie's  wells,  and  others  in  this  township  on  these  beach 
ridges,  pass  thi-ough  gravel  and  sand  5  to  15  feet  and  through  till  below  to 


442  THE  GLACIAL  LAKE  AGASSIZ. 

total  depths  of  30  to  40  feet,  obtaining  water  in  gravelly  seams,  from  which 
it  usually  rises  10  to  20  feet  within  a  few  hours,  to  its  permanent  level. 

East  and  north  of  Duck  Mountain  beaches  of  the  McCauleyville  stages 
are  shown  as  follows  by  Mr.  Tyrrell's  map,  according  to  my  correlation  with 
these  shores  southward  in  Manitoba  and  North  Dakota: 

On  the  Vermilion  River,  which  flows  from  the  northeastern  flank  of 
Riding  Mountain  to  Lake  Dauphin,  the  beach  ridges  of  two  of  these  stages 
are  mapped,  the  elevation  of  the  lower  one  being  noted  as  1,068  feet  above 
the  sea.  Twelve  miles  to  the  northwest  their  elevations  are  1,084  and 
1,075  feet,  at  the  north  side  of  the  Valley  River,  which  flows  from  the  gap 
between  the  Riding  and  Duck  mountains.  Both  these  beaches  are  probably 
represented  by  the  upper  shore-line  farther  south. 

The  higher  beach  was  followed  by  Mr.  Tyi-rell  20  miles  thence  north 
to  the  Shanty  Creek,  but  without  further  notation  of  its  height.  About  20 
miles  farther  north,  near  the  south  side  of  Pine  River,  it  is  found  at  1,175 
feet.  Fifteen  miles  onward,  at  latitude  52°,  close  south  of  Duck  River, 
the  upper  McCauleyville  beach  is  1,201  feet  above  the  sea,  having  thus  an 
ascent  of  117  feet  in  its  course  of  55  miles  from  the  Valley  River.  Three 
miles  beyond  the  Duck  River  where  it  turns  sharply  westward,  adjacent  to 
the  base  of  the  northeastern  angle  of  Duck  Mountain,  its  height  is  1,198 
feet.  After  a  course  of  a  few  miles  to  the  west  the  beach  ridge  of  tliis 
shore,  or  the  foot  of  its  eroded  escarpment,  was  followed  along  the  next  15 
miles  west-southwesterly,  at  the  base  of  the  steep  mountain  slope,  by  the 
original  location  survey  for  the  Canadian  Pacific  Railway. 

Cur^-ing  thence  again  to  the  north,  this  upper  McCauleyville  shore- 
line, where  it  crosses  the  Swan  River,  about  30  miles  west  of  its  crossing 
of  the  Duck  River,  is  marked  by  a  prominent  gravel  ridge  or  embankment 
known  as  the  "Square  Plain,"  1,160  feet  above  the  sea.  It  is  thus  shown 
that  the  former  lake  level  has  now  an  ascent  here  of  a  little  more  than  a 
foot  per  mile  from  west  to  east,  or  about  half  of  its  rate  of  ascent  from 
south  to  north  in  this  district.  The  direction  of  the  differential  uplift,  as  in 
the  southern  part  of  the  lake  area,  was  from  south-soiithwest  to  north- 
northeast,  toward  the  region  on  which  the  ice-sheet  had  been  thickest  and 
where  it  lingered  latest  as  the  barrier  of  Lake  Agassiz. 


CHAPTEE  VIIL 

BEACHES  FORMED  WHEN   LAKE  AGASSIZ  OUTFLOWED 

NORTHEASTWARD. 

Fourteen  shore-lines  of  Lake  Agassiz  have  been  traced,  with  determi- 
nation of  their  heights,  through  portions  of  their  extent,  which  he  Ijelow 
the  McCauleyville  beaches  and  were  formed  after  the  lake  ceased  to  outflow 
southward.  The  River  Warren,  no  longer  receiving  the  drainage  from  the 
melting  ice-sheet  and  from  the  rainfall  of  the  vast  basin  of  Lake  Agassiz, 
was  suddenly  reduced,  when  the  lake  obtained  a  lower  northeastern  outlet, 
to  the  much  smaller  Minnesota  River;  and  the  alluvium  of  this  stream 
formed  a  watershed  between  Lakes  Traverse  and  Big  Stone,  partially  filling 
the  former  channel  of  outflow  from  the  glacial  lake.  Chapter  V  has  already 
considered  the  courses  of  the  successive  new  avenues  of  outflow  to  the 
northeast,  probably  at  first  flowing  back  southward  along  the  border  of 
the  retreating  ice-sheet,  and  thus  passing  through  the  great  Laurentian 
lakes  to  the  Mississippi,  and  later  to  the  Hudson.  Tliough  the  courses  of 
the  northeastward  outlets  remain  unexplored,  the  beaches  marking  the 
stages  of  Lake  Agassiz  while  tributary  to  them  are  found  to  be  separated 
only  by  vertical  intervals  varying-  from  10  or  15  to  45  feet  through  all  the 
time  of  its  reduction  from  the  level  of  Lake  Traverse  and  the  McCauley- 
ville beaches  to  Lake  Winnipeg.  On  the  latitude  of  the  south  end  of  Lake 
Winnipeg  the  fall  of  the  surface  of  the  glacial  lake  during  this  time  was 
about  280  feet.  Lake  Winnipeg  having  stood  at  first  above  its  present 
height  and  having  been  since  lowered  20  feet  by  the  erosion  of  the  Nelson 
River. 

The  tlu-ee  highest  shore-lines  on  the  area  from  which  the  lake  receded 
during  its  northeastward  drainage  are  named  the  Blanchard  beaches,  and 
the  next  five  in  descending  order  the  Hillsboro,  the  two  Emerado,  and  the 
two  Ojata  beaches,  from  towns  on  or  near  their  course  in  North  Dakota. 

443 


444  .  THE  GLACIAL  LAKE  AGASSIZ. 

The  remaining  six,  enumerated  in  the  same  order,  are  designated,  from 
places  of  tlieir  typical  development  in  Manitoba,  as  the  Gladstone,  Burnside, 
Ossowa,  Stonewall,  and  two  Niverville  beaches.  Like  the  shores  marking 
the  higher  stages  of  the  lake  while  flowing  southward,  these  beaches  are 
found  to  have  a  northward  ascent,  due  to  the  differential  uplifting  of  the 
earth's  crust.  The  gradual  decrease  of  their  ascent  from  a  considerable 
amount  along  the  earlier  and  higher  shore-lines  to  very  little  along  the 
latest  and  lowest  shows  that  the  northward  uplifting  was  in  progress  while 
the  ice  barrier  was  receding.  It  had  been  nearly  completed  before  the 
glacial  recession  uncovered  the  area  traversed  by  the  Nelson,  changing 
Lake  Agassiz  to  Lake  Winnipeg. 

Beyond  the  limit  of  my  survey,  which  was  extended  into  Manitoba  to 
Gladstone  and  Orange  Ridge  and  to  the  south  ends  of  Lakes  Manitoba  and 
Winnipeg,  very  interesting  observations  of  the  beaches  east  and  northeast 
of  Riding  and  Duck  mountains  are  supplied  by  Mr.  J.  B.  Tyrrell  in  his 
exploration  of  that  district  for  the  Canadian  Geological  Surve}^^  It  is  there 
found  that  the  earlier  shore-lines  of  the  series  formed  duiinff  the  northeast- 
ern  outflow  were  uplifted  about  a  foot  per  mile  from  south  to  north  for  150 
miles  northward  from  the  latitude  of  Gladstone,  and  that  this  rate  dimin- 
ishes in  the  successively  lower  beaches.  According  to  my  correlation  of 
Mr.  Tyrrell's  observations  with  my  own  in  southern  Manitoba  and  south- 
ward, the  last  shore-line  known  to  have  been  formed  by  Lake  Agassiz  is 
about  60  feet  above  the  south  end  of  Lake  Winnipeg  and  80  feet  above  its 
north  end,  having  thus  a  northward  ascent  of  only  20  feet  in  a  distance  of 
about  275  miles  from  south-southeast  to  north-noi-thwest.  Here,  too,  as  in 
the  earlier  uplifting  of  the  large  region  on  the  sovith,  the  upward  movement 
of  the  earth's  crust  was  interrupted  by  stages  of  repose  or  of  only  very 
slow  progress,  affording  time  for  the  accumulation  of  beach  gravel  and 
sand;  and  these  recognized  shore  marks  are  most  numerous  northward, 
where  the  extent  of  the  uplift  was  greatest.  The  Emerado  beach  thus 
seems  to  be  represented  in  Mr.  Tyrrell's  observations  by  two  beaches  on 

'Geol.  and  Nat.  Hist.  Survey  of  Cauada,  Annual  Report,  new  series,  Vol.  Ill,  for  1887-88,  Part  E, 
16  pages,  with  map.  Bulletin,  G.  S.  A.,  Vol.  I,  1890,  pp.  395-410.  Am.  Geologist,  Vol.  VIII,  pp.  19-28, 
July,  1891. 


BEACHES  WITH  NORTHEASTWARD  OUTFLOW.       445 

Kettle  Hill,  near  the  south  side  of  Swan  Lake,  separated  by  a  vertical 
interval  of  20  feet;  and  the  Niverville  beach  is  subdivided  into  three  at  the 
Grand  Rapids  of  the  Saskatchewan.  Instead  of  the  eleven  or  twelve  shore- 
lines observed  by  me  in  the  United  States  and  in  southern  Manitoba, 
belonging  to  the  time  of  northeastward  outflow,  Mr.  Tyrrell  therefore  has 
at  least  fourteen  upon  the  country  150  to  200  miles  farther  north. 

From  the  following  detailed  descriptions  of  the  beach  deposits  of  these 
lower  shores  it  will  be  seen  that  their  magnitude  and  the  distinctness  of 
their  development  are  very  similar  to  those  of  the  earlier  and  higher  shores 
foimed  during  the  stages  of  southern  outflow.  It  should  be  noted,  how- 
ever, tliat  on  account  of  the  favorable  surtace  of  the  lake  bed  in  North 
Dakota,  consisting  in  large  part  of  gently  sloping  till,  they  are  more  gener- 
ally traceable  there  than  on  the  Minnesota  side  of  the  Red  River  Valley, 
where  some  extensive  tracts,  having  mostly  a  surface  of  silt  with  smaller 
areas  of  till,  were  traversed  and  cursorily  examined  without  detecting  dis- 
tinct shore-lines.  If  they  should  be  more  thoroughly  searched  for  on  these 
tracts,  with  leveling  along  their  known  height,  as  shown  by  their  nearest 
beaches  observed  elsewhere,  doubtless  some  evidences  of  shore  erosion  or 
deposition  would  be  found  almost  continuous,  though  their  character  and 
significance  might  not  be  otherwise  recognizable  with  certainty;  but  it  has 
been  impracticable  to  give  the  time  for  field  work  that  would  be  required  to 
survey  and  map  in  this  manner  the  exact  course  of  these  shores  through 
their  whole  extent.  It  is  believed  that  the  portions  which  have  been 
mapped  with  leveling,  shown  mostly  on  Pis.  XXIII  to  XXXIII,  inserted 
in  Chapter  VI,  are  sufficient  to  show  reliably  the  successive  stages  in  the 
concurrent  uplifting  of  the  land  and  subsidence  of  the  lake. 

BEACHES  OF  THE  BLANCHARD  STAGES. 

Three  successive  levels  of  Lake  Agassiz,  or  pauses  in  the  crustal  uplift 
while  the  lake  shore  passed  near  Blanchard,  N.  Dak.,  seem  to  be  indicated 
by  sand  and  gravel  deposits  which  are  crossed  by  the  Duluth  and  Manitoba 
Railroad  5  to  7  miles  southeast  of  Euclid,  Minn.,  and  by  the  Manitoba  and 
Northwestern  Railway  near  Midway  station,  Manitoba.  The  lowest  of 
these,  however,  has  most  definitely  the  form  of  a  beach  ridge,  and  the 


446  THE  GLACIAL  LAKE  AGASSIZ. 

stage  of  the  lake  to  which  it  belongs,  mapped  on  PL  XXXV,  is  the  only 
one  of  the  three  which  is  generally  marked  plainly  by  a  shore-line  in 
Minnesota  and  North  Dakota. 

With  the  description  of  the  Blanchard  beaches  in  Minnesota,  closely 
associated  portions  of  the  next  lower  or  Hillsboro  beach  are  also  described 
near  Glyndon  and  frora  5  to  15  miles  north  of  Crookston. 

The  principal  and  lowest  Blanchard  shore,  having  a  height  of  about 
925  feet,  crosses  the  Red  River  close  to  Wolverton  station,  on  the  Great 
Northern  Railway,  almost  exactly  halfway  between  Wahpeton  and  Moor- 
head.  Passing  northward  into  Clay  County,  this  shore  is  marked  by  a  belt 
of  gravel  and  sand  thinly  spread  upon  a  broad,  gently  rising  swell  of  till 
which  is  known  as  Pleasant  Ridge,  traceable  in  a  nearly  due-north  course 
about  15  miles  through  the  west  parts  of  Alliance,  Elmwood,  and  Glyndon 
townships.  The  South  Branch  of  the  Buffalo  River  flows  nearly  parallel 
with  it,  at  a  distance  of  a  half  mile  to  1  mile  farther  east.  Shore  currents, 
carrying  southward  much  of  the  gravel  and  sand  derived  from  the  shallow 
wave  erosion  of  the  till  along  the  northern  part  of  the  ridge,  deposited  it 
in  a  rounded  and  partly  almost  flat  tract  a  half  mile  to  tlu-ee-fourths  of 
a  mile  wide  in  the  northwest  part  of  Alliance,  having  a  height  of  925  to 
935  feet  above  the  sea.  Through  Elmwood  and  Glyndon  the  beach  depos- 
its are  narrow  and  scanty,  lying  on  the  western  slope  of  Pleasant  Ridge 
and  along  its  crest.  At  Sabin  they  are  bounded  on  the  west  by  a  typical 
beach  slope,  with  its  top  at  930  feet,  from  which  there  is  a  descent  of  about 
10  feet  westward  within  40  or  50  rods.  In  Glyndon  the  crest  of  the  ridge 
is  in  part  a  sand  and  gravel  beach,  extending  north  tln-ough  the  centers  of 
sections  32,  29,  20,  and  17,  declining  slowly  in  height  from  927  feet  at  the 
south  to  922  feet  at  the  north.  Where  the  continuation  of  this  line  crosses 
the  Northern  Pacific  Railroad  the  surface  was  a  few  feet  below  the  Blanch- 
ard level  of  Lake  Agassiz,  and  no  beach  was  accumulated. 

A  few  miles  south  of  this  railroad  a  scanty  lower  beach  deposit  was 
noted  in  sections  30  and  19,  Glyndon,  tln-ee-fourths  of  a  mile  west  of  the 
preceding,  with  its  crest  at  919  to  921  feet.  This  represents  the  Hillsboro 
stage  of  the  lake,  and,  indeed,  the  formation  of  the  main  beach  in  tliis 
township,  as  just  described,  seems  referable  to  the  time  of  recession  of  the 
lake  betyy^een  the  lower  Blanchard  and  Hillsboro  stages. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL. XXXV. 


.tUnuS  BiCN  SCON 

MAi' OF  THK    S0UTHF:RN   POHTION   OF  LAKK  AGASSIZ,  SHOWING  ITS  EXTKN'I'  IN  THE 

LOWEH   ULANCHARD  STAGK. 

Scide, about  42  iiiilrs  lo  aiiiiicli. 


V 


BLANCHAED  BEACHES  IN  MINNESOTA.  447 

From  Glyudou  to  the  vicinity  of  Crookston  the  Blanchard  shore  is 
mapped  approximately  in  accordance  with  the  known  elevations  and  slope 
of  the  land,  but  its  beaches  have  not  been  examined. 

About  5  miles  northeast  of  Crookston,  in  the  southern  edge  of  section 
3  and  of  the  southwest  quarter  of  section  2  in  this  township,  a  portion  of 
the  Hillsboro  shore-line  extending  a  mile  from  east  to  west  bears  a  well- 
defined,  rather  wide  beach  ridge,  which  rises  5  to  15  feet  above  the  adjoining 
surface  of  till,  with  crest  mostly  936  to  940  feet  above  the  sea.  S.  M. 
McKee's  house  is  built  on  an  exceptionally  high  part  of  this  beach,  at  the 
elevation  of  944  feet,  the  thickness  of  its  sand  and  gravel  there  being  20  feet. 

One  and  a  half  miles  northeast  from  this  beach  deposit  the  lowest 
Blanchard  shore  in  Parnell,  the  next  township  northward,  bears  a  scarcely 
higher  beach  ridge  of  gravel  and  sand,  which  rises  5  to  10  feet  above  the 
adjacent  till  and  extends  northwestward  across  section  35,  having  an 
elevation  at  its  crest  of  935  to  940  feet.  Thence  the  Blanchard  shore  runs 
due  north  or  a  few  degrees  west  of  north  through  Parnell  and  the  next  two 
townships.  It  is  marked  along  the  greater  part  of  this  distance  of  18  miles 
by  a  definite  beach  ridge  which  varies  in  height  from  938  to  946  feet.  A 
half  mile  to  a  quarter  of  a  mile  west  from  this  beach  a  lower  and  smaller 
gravel  and  sand  ridge  on  the  northward  continuation  of  the  Hillsboro  shore, 
with  crest  at  930  to  932  feet,  was  observed  along  a  distance  of  abovit  4 
miles,  passing  nearly  through  the  center  of  section  4,  Parnell,  and  sections 
33,  28,  and  21,  Belgium. 

The  profile  of  the  Duluth  and  Manitoba  Railroad  on  the  south  line  of 
sections  35  and  34,  Belgium,  shows  beach  ridges  of  three  Blanchard  stages, 
with  then-  crests  at  962  feet,  954  feet,  and  946  feet,  in  their  order  from  east 
to  west.  Again,  about  8  miles  farther  north  two  or  three  small  beach 
ridges  of  gravel  and  sand,  lying  on  the  surface  of  till  and  separated  by 
successive  intervals  of  about  a  mile,  were  noted  between  the  lower  Blanch- 
ard and  McCauleyville  beaches.  The  Blanchard  shore-lines  on  the  east 
side  of  Lake  Agassiz  have  not  been  traced  farther  northward,  but  they  are 
known  to  lie  close  west  of  the  McCauleyville  shore  in  its  north-northwest- 
ward course  across  Marshall  and  Kittson  counties,  Miim.,  to  the  international 
boundary. 


448  THE  GLACIAL  LAKE  AGASSIZ. 

lu  Nortli  Dakota  the  lowest  Blancliard  shore  runs  northwestward  from 
the  Red  River  for  its  first  35  miles,  passing  close  west  of  Davenport  and 
close  east  of  Everest  and  Casselton,  but  it  is  not  easily  traceable  across  this 
area  of  lacustrine  silt  associated  with  the  Sheyenne  delta.  Next  it  extends 
north  about  40  miles,  running-  a  few  miles  east  of  Amenia,  Arthur,  and 
Hunter,  and  about  1^  miles  east  of  Greenfield  and  Blanchard.  The  height 
of  this  shore  in  the  distance  of  75  miles  from  the  Red  River  to  Blanchard, 
ascends  from  925  to  935  feet,  approximately,  above  the  sea-level.  It  crosses 
the  Goose  River  about  8  miles  north  of  Blanchard,  and  thence  runs  several 
miles  northeastward,  beyond  which  it  curves  to  the  north,  passing  about 
3  miles  west  of  Cummings  and  1  mile  west  of  Buxton,  where  it  is  marked 
by  a  prominent  beach  ridge,  with  crest  at  945  feet,  very  nearly.  This 
o-ravel  and  sand  ridffe  runs  thence  at  least  15  miles  northwestward.  Near 
the  southwest  corner  of  section  7,  Michigan,  about  11  miles  northwest  from 
Buxton,  its  crest  has  an  elevation  of  942  to  945  feet.  It  there  lies  nearly  4 
miles  east  of  the  principal  McCanleyville  beach,  but  within  a  few  miles 
farther  northwest  the  distance  between  them  is  diminished  to  less  than  2 
miles.  Thence  they  continue  close  together  and  nearly  parallel  through 
their  whole  extent  of  about  80  miles  northward  in  North  Dakota;  but  this 
part  of  the  Blanchard  shore  has  not  been  followed  with  leveling. 

The  shores  formed  during  the  middle  and  upper  Blanchard  stages  of 
Lake  Agassiz  have  not  been  traced  in  North  Dakota.  Their  elevations 
determined  in  Minnesota  and  Manitoba,  however,  indicate  that  Greenfield 
and  Blanchard  are  situated  on  the  middle  shore  or  very  near  it.  A  single 
observation  of  the  upper  shore,  which  passes  about  2  miles  west  of  Blanch- 
ard, was  obtained  7  miles  farther  north.  It  there  is  marked  by  a  low 
escarpment  of  till,  which  descends  3  or  4  feet  from  west  to  east,  between 
965  and  960  feet,  along  a  south-to-north  fine  that  is  crossed  by  the  railway 
about  a  mile  north  of  Murray  station. 

On  the  international  boundary  the  Blanchard  shore-lines  enter  Mani- 
toba in  the  west  part  of  township  1,  range  4,  passing  near  Kronsfeld,  in 
section  7  of  this  township,  and  extending  north-northwest  within  about  a 
mile  east  of  Morden;  but  they  are  not  marked  along  this  distance  by  distinct 
beach  deposits  or  lines  of  erosion.     The  lowest  of  these  shore-hnes  crosses 


WESTERN  BLANCHAED  BEACHES.  449 

the  Canadian  Pacific  Railway  a  mile  west  of  McGregor,  where  it  forms  a 
slight  swell  on  the  gentle  eastward  slope  of  the  Assiniboine  delta.  On  the 
Manitoba  and  Northwestern  Railway  tlu'ee  Blanchard  beaches  appear  to  be 
identifiable,  being  crossed  successively  2  miles  and  three-fourths  of  a  mile 
west  and  1  mile  east  of  Midway.  The  upper  two  are  nearly  flat  tracts 
of  fine  gravel  and  sand,  an  eighth  to  a  quarter  of  a  mile  wide,  at  994  and 
979  feet  above  the  sea,  each  being  bordered  on  the  west  by  a  depression  of 
about  2  feet  and  on  the  east  by  a  gentle  slope  descending  4  or  5  feet.  The 
third  and  lowest  is  a  beach  ridge  of  the  usual  form,  about  30  rods  wide, 
with  a  descent  of  5  feet  both  to  the  east  and  west  from  its  crest,  which  is 
at  969  feet.  After  crossing  the  McCauleyville  beaches  on  the  way  from 
Arden  to  Gladstone  the  surface  is  wholly  silt  and  sand,  with  fine  gravel, 
very  flat,  excepting  these  slight  ridges  and  others  at  lower  levels.  In  their 
continuation  northward,  portions  of  the  Blanchard  beaches  are  noted  on  the 
plats  of  the  Dominion  Land  Surveys  through  townships  15  to  20,  range  13. 
The  highest  of  the  Blanchard  shores  is  probably  represented  on  Mr. 
Tyrrell's  map  of  the  Riding  and  Duck  mountains  by  two  observations  of 
beach  ridges,  namely,  on  the  Ochre  River,  about  8  miles  south  of  Lake 
Dauphin,  at  1,025  feet  above  the  sea;  and  on  latitude  52°,  close  south  of 
the  Duck  River,  at  1,151  feet.  A  few  miles  north  of  the  Duck  River  the 
second  Blanchard  beach,  according  to  my  correlation,  is  shown  at  the  height 
of'  1,135  feet;  and  the  third  and  lowest  beach  formed  during  these  stages 
appears  to  be  represented  on  the  north  side  of  Swan  River,  nearly  25  miles 
farther  west,  by  a  beach  approximately  at  1,070  feet,  being  100  feet  liigher 
than  near  Midway,  on  the  latitude  of  Gladstone,  about  160  miles  distant  to 
the  south-southeast. 

THE    HILIiSBORO    BEACH. 

My  only  observations  of  the  shore-line  in  Minnesota  which  seems  ref- 
erable to  the  Hillsboro  stage  of  Lake  Agassiz,  excepting  as  already  noted 
with  the  descriptions  of  the  Blanchard  beaches,  were  in  Alma  and  Wanger 
townships,  Marshall  County. 

A  somewhat  broad  beach  ridge,  915  to  923  feet  above  the  sea,  consist- 
ing of  gravel  and  sand  on  an  area  of  till,  extends  from  a  cemetery  in  the 
MON  XXV 29 


450  THE  GLACIAL  LAKE  AGASSIZ. 

northeast  comer  of  section  26,  Alma,  northward  through  the  east  edge  of 
sections  23  and  14  to  the  Middle  River.  This  deposit,  however,  is  about 
15  feet  lower  than  would  seem  accordant  with  the  Hillsboro  beach  5  to  15 
miles  north  of  Crookston  and  on  the  opposite  side  of  the  lake  in  North 
Dakota,  while  yet  it  is  distinct  from  the  next  lower  Emerado  beach,  which 
was  observed  at  its  normal  elevation  a  mile  distant  to  the  west.  The  low 
position  of  the  Hillsboro  beach  here  may  be  due  to  its  subdivision  in 
advancing  from  south  to  north,  this  beach  being  referable  to  a  secondary 
Hillsboro  stage;  otherwise  it  would  imply  a  noteworthy  and  very  excep- 
tional irregularity  in  the  crastal  uplift. 

Probably  the  same  Hillsboro  shore  continues  north  through  the  dis- 
tance of  6  miles  to  another  beach  ridge  noted  on  the  Tamarack  River,  in  or 
near  the  west  edge  of  sections  13  and  12,  Wanger.  A  search  with  leveling 
to  the  south  and  north  from  these  localities  would  quite  surely  prove  this 
shore  to  be  traceable  through  long  distances  on  the  east  side  of  the  lake. 

The  elevation  of  the  Hillsboro  shore  where  it  crosses  the  Red  River, 
near  Holy  Cross  and  Hickson  stations,  about  15  miles  south  of  Moorhead 
and  Fargo,  is  approximately  915  feet.  Thence  its  course  in  North  Dakota 
is  first  northwestward  about  20  miles,  passing  by  Horace,  to  Durbin,  on 
the  Maple  River.  It  here  lies  on  an  area  of  fine  silt,  and  is  not  distinctly 
marked  either  by  a  beach  ridge  or  by  erosion. 

Along  the  northwest  and  north  side  of  the  Maple  River,  at  an  average 
distance  from  it  decreasing  from  2  miles  to  1  mile,  a  prolonged  beach  of 
sand  and  fine  silt  (mapped  on  PI.  XXVIH)  was  formed  by  erosion  from  the 
margin  of  the  Sheyenne  delta  and  from  the  adjoining  lake  bed,  and  by 
transportation  toward  the  northeast  and  east,  being  thus  built  out  into  the 
lake  as  a  spit,  during  the  Blanchard  and  Hillsboro  stages.  This  spit,  which 
is  sometimes  called  the  Maple  Ridge  from  its  ijarallehsm  with  the  Maple 
River,  is  crossed  by  the  Great  Northern  Railway  2  miles  northwest  of  Dur- 
bin. It  is  there  a  wave-like,  massive  swell  about  50  rods  wide,  rising  10 
feet  above  the  flat  expanse  on  each  side,  with  its  top  930  feet  above  the 
sea,  showing  that  this  portion  was  formed  during  the  time  of  the  Blanchard 
beach.  Six  miles  to  the  northeast,  where  it  is  crossed  by  the  Northern 
Pacific  Railroad  at  Greene,  it  has  a  width  of  60  rods,  with  its  crest  at  919 


THE  HILLSBORO  BEACH.  451 

feet,  from  which  its  eastern  slope  descends  10  feet  and  its  western  slope 
about  5  feet.  This  part  of  the  Maple  Ridge  was  accumulated  by  Lake 
Agassiz  at  the  stage  of  the  Hillsboro  beach,  rising  then  only  2  or  3  feet 
above  the  level  of  the  lake.  Following  the  ridge  onward  9  miles  farther  to 
the  northeast  and  east,  it  is  found  to  become  broader  and  less  definite,  and 
its  height  sinks  slowly  about  20  feet  to  900  or  895  feet  in  the  south  edge  of 
section  13,  Raymond,  about  a  quarter  of  a  mile  north  of  the  Maple  River, 
where  it  ceases  to  be  traceable  even  as  a  slight  swell  above  the  general 
level  of  the  surrounding  expanse  of  lacustrine  and  alluvial  silt.  Shore 
currents  appear  to  have  come  together  from  both  the  north  and  south  along 
this  curved  spit  while  the  Bianchard  and  Hillsboro  beaches  were  being 
accumulated  and  during  the  fall  of  the  lake  surface  below  each  of  these 
stages. 

From  the  vicinity  of  Greene  the  Hillsboro  shore-line  rans  northward 
50  miles,  passing  about  3  miles  west  of  Grandin  and  Kelso,  IJ  miles  west 
of  Hillsboro,  about  three-fourths  of  a  mile  east  of  Cummings,  and  1  mile 
west  of  Buxton.  Opposite  to  Grandin  and  Kelso  it  is  marked  by  a  typical 
gravel  and  sand  ridge,  with  slopes  descending  10  feet  on  the  east  and  5  or 
6  feet  on  the  west  to  the  adjoining  surface  of  till.  Mr.  R.  T.  Kingman's 
house,  west  of  Hillsboro  and  close  south  of  the  Goose  River,  is  built  on 
the  crest  of  the  Hillsboro  beach  ridge  of  gravel  and  sand,  at  an  elevation  of 
about  920  feet  above  the  sea.  The  slopes  of  this  beach  fall  about  15  feet 
toward  the  east  and  5  feet  westward.  Within  a  quarter  of  a  mile  farther 
west,  an  escarpment  of  till  rises  10  feet,  from  915  to  926  feet,  a23proxi- 
mately,  having  been  cut  by  the  waves  of  the  lake  when  it  stood  a  few  feet 
above  its  later  level  by  which  the  beach  ridge  was  deposited.  One  and  a 
half  miles  south  of  Mr.  Kingman's  the  Hillsboro  shore  has  no  beach  deposit, 
being  indicated  only  by  an  escarpment  of  till  which  rises  6  to  10  feet  within 
a  distance  of  15  to  20  rods  from  east  to  west. 

A  slightly  higher  shore-line,  marked  by  an  escarpment  6  to  8  feet  high, 
eroded  in  fine  silt,  was  observed  a  mile  west  of  each  of  these  localities,  being 
thus  traced  about  2  miles  southward  from  the  Goose  River. 

Three  pauses  in  the  crustal  uplift  are  thus  shown  near  Hillsboro  by 
the  former  levels  of  Lake  Agassiz,  approximately  at  925  or  928  feet,  920 


452  THE  GLACIAL  LAKE  AGASSIZ. 

feet,  aud  915  feet,  represented  successively  by  the  western  escarpment  of 
silt,  tlie  eastern  escarpment  of  till,  and  the  shore  deposit  of  sand  and  gravel 
at  Mr.  Kingman's  house.  Elsewhere  these  stages  seem  to  be  united,  unless 
the  lower  one  was  also  observed,  as  before  noted,  in  Marshall  County,  Minn. 

Where  it  is  crossed  by  the  Great  Northern  Railway,  2  miles  south  of 
Cummings,  the  Hillsboro  shore  is  an  eroded  escarpment  of  till,  ascending 
somewhat  steeply  8  or  10  feet,  with  no  considerable  beach  deposits.  Con- 
tinuing thence  on  the  east  side  of  the  railway  for  12  miles  northward  by 
Cummings  and  Buxton,  it  is  marked  through  nearly  the  entire  distance  by  a 
conspicuous  beach  ridge  of  gravel  and  sand,  bordered  on  each  side  by  till. 
The  crest  of  this  beach  is  925  to  930  feet  above  the  sea,  with  an  average 
descent  of  10  feet  to  the  east  and  5  feet  to  the  west.  At  its  next  intersec- 
tion by  the  railway,  1^  miles  south  of  Reynolds,  the  gravel  and  sand  of  the 
beach  have  been  extensively  excavated  for  railway  ballast.  The  ridge 
there  is  about  30  rods  wide;  the  elevation  of  its  crest  is  928  feet,  and  its 
slopes  to  the  northeast  and  northwest  fall  respectively  about  8  and  6  feet. 

Through  its  further  course  of  about  100  miles  in  North  Dakota  this 
shore-line  runs  to  the  northwest  and  north-northwest,  excepting  that  it 
deviates  to  a  north-northeastward  course  for  15  miles,  between  the  North 
Branch  of  Park  River  and  Tongue  River,  turning  thus  aside  to  pass  by  the 
Pembina  delta.  In  section  27,  Michigan,  about  3  miles  northwest  of  Rey- 
nolds, the  crest  of  its  beach  ridge  is  926  feet  above  the  sea,  having  a  descent 
of  6  feet  eastward  aud  3  feet  westward.  In  section  16  of  this  township  the 
beach  is  a  broad,  flattened  ridge  of  sand  and  fine  gravel,  about  40  rods 
wide,  with  top  at  923  to  926  feet.  It  slowly  rises  10  feet  above  the  flat 
surface  of  till  on  the  east,  and  descends  3  to  5  feet  westward  to  a  depression 
which  is  partly  a  grassy  slough  mown  for  hay.  Through  its  next  mile 
northwestward  the  shore  is  an  escarpment  of  till,  rising  a  few  feet,  with  its 
crest  at  923  feet. 

No  exact  determination  of  the  height  of  the  Hillsboro  shore  was  obtained 
along  its  next  25  miles  to  the  southeast  part  of  section  25,  township  153, 
range  54,  about  2  miles  west  of  Beans  station,  on  the  Duluth  and  Manitoba 
Railroad,  where  the  crest  of  its  gravel  and  sand  ridge  is  very  nearly  930 
feet  above  the  sea.     Again,  about  20  miles  farther  north  the  beach  ridge 


THE  HILLSBOEO  BEACH.  453 

of  this  shore  has  the  same  height,  or  930  to  935  feet,  in  sections  25,  24,  and 
13,  Rushford.  Thence  through  an  extent  of  about  50  miles  to  the  inter- 
national boundary,  although  the  course  of  the  Hillsboro  shore  is  mapped 
approximately  on  PI.  XXX,  its  height  is  known  by  leveling  in  only  one 
place,  near  the  center  of  section  15,  Walhalla,  about  2  J  miles  northeast  of 
Walhalla  village,  where  the  top  of  the  beach  is  940  feet  above  the  sea, 
rising  15  feet  above  its  base  20  rods  distant  to  the  east  and  bordered  by  a 
depression  of  2  to  5  feet  on  the  west. 

The  Hillsboro  beach  enters  Manitoba  near  the  middle  of  the  south  side 
of  range  4  and  passes  north-northwestward.  It  is  not  conspicuous  on  the 
international  boundary,  but  near  the  west  line  of  section  21,  township  1, 
range  4,  about  a  mile  east  of  Blumenfeld,  it  is  a  noticeable  ridge,  with  a 
descent  of  3  to  5  feet  on  the  east,  its  crest  being  about  940  feet  above  the 
sea.  Its  sand  has  there  been  excavated  for  use  in  plastering.  Northward 
it  passes  about  a  half  mile  east  of  Oesterwick,  1 J  miles  east  of  Morden,  and 
nearly  4  miles  east  of  Miami,  where  Henry  York's  house  is  built  on  its 
crest,  at  an  elevation  of  about  950  feet.  Thence  its  slopes  descend*15  feet 
in  a  short  distance  to  the  east  and  5  feet  or  more  to  tlie  west,  the  beach 
being  much  larger  than  along  most  of  its  course.  Mr.  York's  cellar  and 
well  are  in  sand  and  fine  gravel,  but  the  lower  land  adjoining  on  each  side 
is  till.  Twelve  miles  farther  north  this  beach  passes  near  Mr.  Field's  house, 
in  the  southeast  quarter  of  section  4,  township  7,  range  6,  about  three- 
fourths  of  a  mile  west  of  Almasippi  post-office.  The  road  from  Carman  to 
Treherne  there  ascends  a  few  feet,  and  in  its  next  third  of  a  mile  northwest- 
ward crosses  a  tract  of  sand  with  hollows  3  to  5  feet  below  its  highest 
portions,  showing  that  it  was  formerly  wind-blown.  This  beach  deposit  is 
derived  from  the  erosion  of  the  eastern  margin  of  the  Assiniboine  delta, 
within  a  few  miles  to  the  north.  On  the  road  from  Arden  to  Gladstone 
this  beach  was  not  noticed,  but  it  seems  to  be  traceable  on  the  township 
plats  northward  nearly  through  the  middle  of  townships  15,  16,  and  17, 
and  through  the  west  part  of  townships  18,  19,  and  20,  in  range  12. 

On  the  Swan  River  and  its  tributaries,  north  of  Duck  Mountain,  the 
Hillsboro  beach,  according  to  my  correlation  of  Mr.  Tyrrell's  observations, 
has  been  traced  fragmentarily  along  a  distance  of  20  miles  from  east  to 


454  THE  GLACIAL  LAKE  AGASSIZ. 

west,  having  an  elevation  of  about  1,030  feet  above  the  sea;  and  it  was 
again  noted  at  the  height  of  1,070  feet  some  30  miles  farther  northeast.  On 
Kettle  Hill,  close  south  of  Swan  Lake. 

BEACHES    or    THE    EMERADO    STAGES. 

The  Emerado  shore-line,  approximately  885  feet  above  the  sea,  crosses 
the  Red  River  between  Kragnes,  Minn.,  and  Harwood,  N.  Dak.,  a  few  miles 
north  of  Moorhead  and  Fargo;  but  its  course  has  not  been  traced  for  the 
first  50  miles  thence  northward  to  the  vicinity  of  Crookston,  Minn.,  and 
Reynolds,  N.  Dak.  Tln-otigh  both  of  these  States  it  appears  as  a  single 
shore-line,  and  is  perhaps  the  one  most  clearly  traceable  of  all  that  belong 
to  the  time  of  northeastward  outflow.  The  crustal  uplifting  of  this  part 
of  the  lake  basin  had  become  very  slow  at  the  time  of  formation  of  the 
Emerado  beach,  but  in  Manitoba  a  somewhat  rapid  uplift  was  in  progress, 
increasing  in  amount  from  south  to  north,  and  two  beaches  there,  separated 
by  a  vertical  interval  of  10  to  20  feet,  seem  to  represent  the  single  beach 
farther  south. 

In  the  west  part  of  sections  17,  8,  and  5,  Ci'ookston,  a  beach  ridge  of 
the  Emerado  stage  was  traced  2  miles  in  a  nearly  due-north  course.  Har- 
vey Cook's  house,  in  the  south  edge  of  section  8,  is  built  on  its  top,  which 
ranges  in  height  from  898  to  902  feet  above  the  sea,  having  a  descent  of 
10  or  12  feet  on  the  west  and  half  as  much  on  the  east.  About  a  mile 
northwest  from  the  north  end  of  this  beach  irregular  and  short  gravel  and 
sand  ridges,  accumulated  on  an  area  of  till,  mark  this  shore  on  the  Great 
Northern  Railway,  and  extend  thence  close  along  its  east  side  2  miles  north- 
ward to  Shirley,  the  elevations  of  their  crests  being  905  to  910  feet. 
Portions  of  these  deposits  have  been  excavated  for  railway  ballast. 

From  1  to  2  miles  north  of  Shirley  the  Emerado  beach  is  a  typical 
and  continuous  gravel  ridge,  with  crest  at  910  feet,  approximately,  rising 
about  5  feet  above  the  adjoining  surface  of  till.  Here  and  through  the 
next  3  miles  northward  the  shore  lies  an  eighth  to  a  half  of  a  mile  east  of 
the  railway.  It  continues  in  a  nearly  due-north  course  through  the  west 
edge  of  Belgium  and  of  township  153,  range  46,  passing  li  miles  east  of 


THE  BMERADO  BEACHES.  455 

Euclid  and  4  miles  east  of  Angus.  In  the  southeast  part  of  Angus  Town- 
ship and  tlie  southwest  part  of  township  153,  range  46,  its  beach  deposits 
of  gravel  are  somewhat  irregularly  accumulated  in  three  belts  lying  on  an 
area  of  till  and  separated  by  intervals  of  about  1  mile  and  a  half  mile  in 
order  from  east  to  west.  The  crests  of  these  short  gravel  ridges  vary  in 
elevation  from  900  to  905  feet,  their  higher  portions  being  usually  3  to  5 
feet  above  the  surface  on  their  east  side  and  6  to  8  feet  above  the  land 
next  west. 

Twelve  miles  north  of  Angus  a  short  beach  ridge  of  gravel  and  sand, 
having  nearly  the  same  height  with  the  foregoing,  was  noted  on  the  east 
edge  of  section  1 5,  McCrea,  close  south  of  a  creek  tributary  to  the  Snake 
River.  Again,  4  to  5  miles  farther  north,  a  broad,  irregular  sand  lieach, 
with  crest  at  905  feet,  being  3  to  5  feet  above  the  general  level,  runs  along 
the  east  line  of  section  22,  Alma.  It  reaches  a  mile  or  more  south  from  the 
Middle  River,  and  is  a  mile  west  of  the  Hillsboro  beach.  Its  surface  has 
been  somewhat  changed  into  small  ridges  and  hollows  by  wind  action  at 
some  former  time,  but  it  is  now  wholly  covered  by  grass.  Thence  the 
Emerado  shore  runs  nearly  due  north  throug-h  Wander  and  Auffsbura-, 
townships  157  and  158,  range  47,  as  shown  by  their  contour;  but  it  has  not 
been  traced  there  nor  in  its  farther  course,  which  is  slightly  west  of  north 
through  Kittson  County  to  the  international  boundary. 

In  North  Dakota  the  Emerado  shore-line  runs  nearly  along  the  Great 
Northern  Railway  by  Harwood,  Argusville,  Gardner,  and  Grandin,  and 
within  1  to  1|  miles  east  of  Kelso,  Alton,  and  Hillsboro;  but  most  of  its 
course  is  not  distinctly  traceable  on  the  flat  surface  of  fine  silt  which  is 
crossed  in  this  distance  of  30  miles.  Through  the  next  tlu-ee  townships 
north  of  Hillsboro,  passing  Cummings  and  Buxton,  it  lies  IJ  to  2  miles 
east  of  the  railway,  but  approaches  within  about  1  mile  at  Reynolds.  The 
Emerado  shore  here  traverses  a  large  area  of  till,  which  reaches  eastward 
across  the  Red  River  Valley.  On  this  more  favorable  surface  it  is  doubt- 
less clearly  marked,  like  the  next  higher  Hillsboro  shore,  by  a  well-defined 
beach  ridge,  or  in  part  by  a  low,  eroded  escarpment. 

The  railway  intersects  this  beach  ridge  1.^  miles  north  of  Reynolds, 
its  crest  being  about  900  feet  above  the  sea,  with  descent  of  3  or  4  feet 


456  THE  GLACIAL  LAKE  AGASSIZ. 

to  the  southwest  and  8  or  10  feet  to  the  northeast.  Thence  the  Emerado 
shore  runs  north-northwesterly  70  miles  tlu-ough  Grand  Forks  and  Walsh 
counties.  In  sections  20  and  17,  Allendale,  9  to  10  miles  northwest  of 
Reynolds,  it  bears  an  excellent  gravel  ridge,  which  rises  10  feet  from  its 
northeast  base  and  3  to  5  feet  above  the  surface  on  the  southwest,  the  land 
on  both  sides  being  till.     The  elevation  of  its  crest  is  898  to  902  feet. 

At  Emerado,  on  the  Devils  Lake  line  of  the  Great  Northern  Railway, 
this  beach  is  crossed  less  than  a  quarter  of  a  mile  east  of  the  station.  Its 
crest  is  894  feet  above  the  sea,  being  10  feet  above  the  adjacent  surface  of 
till  on  the  east ;  but  within  the  next  mile,  both  to  the  southeast  and  north- 
west, its  height  is  mostly  895  to  900  feet.  Two  to  3  miles  northwest,  in 
section  26,  Mekinock,  the  crest  of  the  beach  lies  at  897  to  900  feet,  with  a 
descent  of  5  to  8  feet  eastward  and  half  as  much  toward  the  west. 

In  sections  33,  32,  and  29,  Gilby,  the  Emerado  beach  ridge  is  mag- 
nificently developed,  passing  close  west  of  Beans  station,  on  the  Duluth 
and  Manitoba  Railroad.  The  top  of  the  beach  has  an  elevation  of  898  to 
902  feet,  with  descents  of  about  10  feet  in  15  or  20  rods  east  and  3  to  5 
feet  within  10  rods  west  to  very  flat  expanses  of  till  on  each  side.  Again, 
in  sections  19  and  18,  Gilby,  it  has  the  same  character  and  elevation;  but 
in  the  northwest  part  of  section  7  and  on  the  west  line  of  this  township, 
also  thence  northward  3  miles  into  section  25,  Strabane,  there  is  no  beach 
deposit,  its  place  being  taken  by  an  escarpment  of  till,  6  to  8  feet  high, 
with  its  top  at  900  to  902  feet.  Northward  from  the  northwest  part  of  this 
section  25,  Strabane,  the  Emerado  shore  is  again  marked  by  the  usital 
ridged  deposit  of  gravel  and  sand,  with  its  crest  very  level,  varying  not 
more  than  a  foot  above  or  below  901  feet  in  its  extent  of  about  3  miles  to 
the  Forest  River. 

Entering  Walsh  County,  the  crest  of  this  beach  ridge  in  sections  35 
and  34,  Ops,  is  still  901  feet  above  the  sea,  with  descent  thence  of  6  or 
7  feet  in  6  rods  northeastward  and  4  feet  in  the  same  distance  to  the 
southwest.  Through  sections  27,  22,  16,  9,  and  4,  Ops,  it  also  holds  very 
constantly  the  same  character  and  height,  900  to  902  feet,  being  a  typical 
ridge  of  sand  and  gravel,  lying  on  till.     In  the  east  half  of  section  29, 


THE  EMBEADO  BEACHES.  457 

Prairie  Center,  its  elevation  is  903  feet,  and  it  continues  as  a  well-defined 
gravel  ridge,  with  crest  at  901  to  903  feet,  through  tliis  township,  and  at  a 
slightly  greater  lieiglit,  902  to  906  feet,  through  the  west  part  of  Fertile 
and  the  east  part  of  Dundee,  crossing  the  South  and  Middle  branches  of 
Park  River. 

In  the  southern  part  of  Pembina  County  the  Emerado  shore  curves  to 
a  north-northeast  course,  passing  by  Crystal  to  Willow  Creek,  and  thence 
runs  nearly  north,  crossing  the  Tongue  River  about  a  mile  west  of  Cavalier. 
Along  a  distance  of  6  miles  north  from  Willow  Creek  a  low  and  broad 
secondary  beach  ridge,  or  more  likely  in  part  an  offshore  sand  deposit  that 
was  formed  a  few  feet  beneath  the  lake  surface,  has  an  elevation  of  890 
to  895  feet,  with  slopes  sinking  a  few  feet  below  this  on  each  side.  The 
adjoining  surface  is  lacustrine  silt,  deposited  in  front  of  the  Pembina 
delta,  and  the  ridge  is  fine  sand  which  has  been  somewhat  gullied  and 
hummocked  by  the  wind,  but  is  now  all  grassed. 

Between  the  Tongue  and  Pembina  rivers  and  onward  to  the  inter- 
national boundary  this  beach  takes  a  northwestward  course.  Turning  to 
that  direction  about  2  miles  northwest  of  Cavalier,  it  thence  runs  nearly 
straight  10  miles  to  St.  Joseph,  being  through  the  greater  part  of  the  dis- 
tance a  typical  beach  ridge  of  sand,  with  scanty  layers  of  very  fine  gravel. 
Its  crest  is  mainly  892  to  898  feet  above  the  sea,  having  a  gradual  ascent 
from  south  to  north ;  but  as  it  approaches  St.  Joseph  and  the  Pembina 
River  its  last  2  miles  rise  to  900  and  even  905  feet.  The  slopes  fall  com- 
monly 5  to  10  feet  northeastward  and  2  to  4  feet  southwestward.  The 
depth  of  the  beach  deposit  is  the  same  as  the  fall  of  its  eastern  slope,  with 
hard  and  dark  stratified  clay  beneath.  In  section  2,  and  again  in  section 
13,  township  162,  range  55,  lying  2  to  5  miles  southeast  of  St.  Joseph,  this 
beach  widens  into  sandy  tracts,  each  of  which  has  a  width  of  a  quarter  of 
a  mile  or  more  and  is  slightly  raised,  like  the  typical  narrower  ridge,  above 
the  adjacent  surface  of  clayey  lacustrine  and  alluvial  silt. 

About  a  mile  north  of  the  Pembina  River  the  Emerado  level  of  Lake 
Agassiz  formed  a  low  escarpment  of  erosion,  which  passes  north-northwest- 
erly by  the  northeast  corner  of  section  17,  townsliip  163,  range  55.    Within 


458  THE  GLACIAL  LAKE  AGASSIZ. 

40  rods  or  less  from  west  to  east  it  descends  about  10  feet,  from  905  to 
895  feet  above  the  sea,  approximately. 

The  Emerado  beach  crosses  the  international  boundary  about  1 J  miles 
east  of  the  west  line  of  range  3,  Manitoba,  passing  thence  northwestward. 
In  townships  1  and  2,  range  4,  the  Mennonite  villages  of  Rheinland,  Neuen- 
burg,  and  Eosenthal  are  partly  built  on  it.  At  the  windmill  in  Rheinland, 
and  thence  along  its  course  as  seen  for  a  half  mile  or  more  to  the  south- 
southeast  and  north-northwest,  this  shore  is  marked  by  an  ascent  of  3  to  6 
feet  in  as  many  rods  from  east  to  west;  and  from  its  crest,  about  905  feet 
above  the  sea,  the  surface  extends  nearly  level  westward.  The  beach 
consists  of  loamy  sand,  while  the  adjoining  land  is  fine  lacustrine  silt  or 
clay.  On  the  Canadian  Pacific  Railway  this  beach  is  raised  a  few  feet 
above  the  general  slope  of  the  Assiniboine  delta,  passing  in  a  west-north- 
west course  2  miles  east  and  1  mile  north  of  Bagot.  The  Manitoba  and 
Northwestern  Railway  crosses  it  5  miles  west  of  Gladstone,  where  it  is  a 
ridffe  about  30  rods  wide,  wind-blown  in  hollows  1  to  2  feet  below  the 
crest,  which  is  927  to  929  feet  above  the  sea,  with  descent  of  5  feet  from  it 
to  the  west  and  12  to  15  feet  to  the  east.  A  lower  and  less  conspicuous 
beach  ridge,  also  belonging  to  this  stage,  lies  three-fourths  of  a  mile  farther 
east,  with  its  crest  at  916  feet.  The  Emerado  beach  continues  north 
through  the  east  part  of  townships  15  to  19,  range  12,  and  through  the 
center  of  township  20,  to  the  east  side  of  Lake  Mary. 

Two  Emerado  stages  are  again  noted  by  Mr.  Tyrrell,  according  to  my 
correlation,  at  the  heights  of  1,015  and  995  feet  above  the  sea,  as  shown 
by  beaches  on  Kettle  Hill,  about  150  miles  north  of  Gladstone.  The  upper 
beach  has  an  ascent  of  95  feet  in  this  distance,  and  the  lower,  85  feet, 
approximately. 

The  lower  of  these  shores,  which  is  the  more  strongly  marked  on 
Kettle  Hill,  is  probably  also  shown  by  a  beach  ridge  mentioned  by  Tyrrell 
near  the  Pine  River,  some  40  miles  farther  south,  at  a  height  of  960  feet 
above  the  sea,  as  determined  by  the  original  location  of  the  Canadian 
Pacific  Railway. 


OJATA  BEACHES  IN  MINNESOTA.  459 

BEACHES  OF  THE  OJATA  STAGES. 

The  upper  Ojata  shore-line  has  an  elevation  between  870  and  875  feet 
above  the  sea  where  it  crosses  the  Red  River  near  Perley,  Minn.,  and 
Noble,  N.  Dak.,  about  20  miles  north  of  Moorhead  and  Fargo.  Its  course 
in  Minnesota  has  been  mapped  approximately  for  25  miles  through  Norman 
County,  lyiiig  from  2  to  6  miles  east  of  the  river,  according  to  the  contour 
shown  by  the  Drainage  Survey;  but  it  is  not  known  how  much  of  the  shore 
is  there  marked  by  any  beach  ridge  or  line  of  erosion.  Probably  a  con- 
siderable part  is  thus  definitely  traceable,  especially  northward,  where  the 
surface  is  till. 

After  curving  eastward,  near  the  boundary  between  Norman  and  Polk 
counties,  to  a  distance  of  10  miles  from  the  Red  River,  this  shore  turns  to 
the  north  and  north-northwest,  crossing  the  east  part  of  the  great  marsh 
which  is  formed  by  the  waters  of  the  Sand  Hill  River  and  of  many  springs. 
In  the  northeastern  edge  of  this  marsh  it  bears  a  conspicuous  beach  ridge, 
which  runs  from  near  the  center  of  section  10,  township  147,  range  47,  6 
miles  to  the  north  side  of  section  18,  Hammond.  The  crest  of  the  dry 
ridge  of  sand  and  gravel  is  873  to  878  feet  above  the  sea,  and  the  surface 
of  the  marsh  adjoining  it  is  about  3  feet  lower  on  the  east  and  5  feet  lower 
on  the  west. 

About  2  miles  northwest  from  Crookston  a  large  beach  deposit  of 
gravel  and  sand  on  this  shore-line  is  crossed  by  the  Great  Northern 
Railway  in  sections  24  and  23,  Lowell,  and  has  been  much  excavated  for 
railway  ballast.  The  elevation  of  its  crest  is  880  to  882  feet,  and  its  thick- 
ness is  3  to  5  feet,  lying  on  till.  The  pebbles  of  the  gravel  seldom  exceed 
3  inches  in  diameter,  and  are  mostly  magnesian  limestone,  similar  to  the 
strata  which  outcrop  near  Winnipeg. 

The  Drainage  Survey  shows  that  the  farther  course  of  this  shore  is 
nearly  due  north  for  the  next  40  miles,  passing  about  2  miles  west  of 
Shirley,  a  mile  west  of  Euclid,  IJ  miles  east  of  Angus,  about  3  miles  east 
of  Warren,  and  5  miles  east  of  Argyle.  Through  the  greater  part  of  this 
extent  it  lies  on  or  near  the  western  edge  of  the  till,  which  is  succeeded 
toward  the  Red  River  by  lacustrine  and  alluvial  silt.     In  a  few  places  the 


460  THE  GLACIAL  LAKE  AGASSIZ. 

shore  is  known  to  be  indicated  by  erosion  or  by  gravel  and  sand  dejiosits, 
bnt  more  commonly  it  is  not  clearly  ti-aceable.  It  thence  runs  slightl)' 
west  of  north  to  the  international  boundary,  but  has  not  been  examined 
along  that  distance  of  nearly  50  miles. 

Lying  about  10  feet  below  the  preceding,  the  lower  Ojata  shore  crosses 
the  Red  River  near  Caledonia  and  the  mouths  of  the  Goose  and  Marsh 
rivers,  being  there  about  8(j5  feet  above  the  sea.  From  5  to  12  miles  north- 
ward in  Minnesota  it  runs  along  the  west  margin  of  the  great  marsh  of  tlie 
Sand  Hill  River.  Onward  through  this  State  it  must  lie  mostly  1  to  2  miles 
west  of  the  upper  Ojata  beach,  though  generally  it  is  indistinct  and  its 
course  has  been  nowhere  exactly  noted. 

Portions  of  the  Ojata  beaches  in  North  Dakota  have  come  under  my 
observation  from  the  vicinity  of  Reynolds  and  Thompson  north-northwest- 
ward across  Grand  Forks  and  Walsh  counties.  The  upper  shore  is  not 
clearly  exhibited  where  it  is  crossed  by  the  Great  Northern  Railway,  about 
2  miles  south  of  Thompson,  but  the  lower  shore  is  marked  by  a  beach  ridge 
of  gravel  and  sand,  which  is  crossed  1  mile  north  of  this  station.  The  crest 
is  about  868  feet  above  the  sea,  with  descent  of  6  to  8  feet  from  it  toward 
the  northeast  and  2  or  3  feet  southwestward. 

On  the  south  line  of  section  36,  Oakville,  and  of  section  31,  Brenna,  7 
to  8  miles  northwest  from  Thompson  and  5  miles  south  of  Ojata,^  the 
heights  of  the  crests  of  the  well-developed  upper  and  lower  Ojata  beaches 
are  respectively  about  880  feet  and  872  to  875  feet.  One  to  2  miles  south- 
eastward, however,  these  shore-lines  have  neither  beach  deposits  nor  any 
notable  erosion  on  the  -smooth,  gently  sloping  /surface  of  till. 

The  Great  Northern  Railway  between  Emerado  and  Ojata  intersects 
the  crest  of  the  upper  Ojata  shore-line  a  quarter  of  a  mile  west  of  the 
northeast  corner  of  section  8,  Oakville,  about  3  miles  west  of  Ojata.  It 
consists  of  a  somewhat  prominent  escarpment  of  till,  which  falls  from  west 
to  east  at  first  7  or  8  feet  within  15  or  20  rods,  and  as  much  more  within 
the  next  third  of  a  mile,  its  base  being  862  to  865  feet  above  the  sea,  whence 

•Meaning  /oj-fc»  in  the  Dakota  or  Sioux  language,  and  referring,  like  Grand  Forks,  to  the  junc- 
tion of  the  Red  and  Red  Lake  rivers  (A.  W.  Williamson,  in  Thirteenth  Annual  Report,  Geol.  and 
Nat.  Hist.  Survey  of  Minnesota,  for  1884,  p.  110). 


OJATA  BEACHES  IN  NORTH  DAKOTA.  461 

a  very  flat  and  almost  level  surface  of  till,  with  alkaline  soil,  extends  east- 
ward. The  top  of  the  escarpment  is  capped  to  the  depth  of  a  few  feet  with 
beach  gravel  and  sand,  at  877  and  880  feet,  deposited  during  the  upper 
Ojata  stage  of  the  lake,  and  the  erosion  of  the  steep  slope  below  may  have 
been  accomplished  mostly  during  a  lower  and  later  portion  of  this  stage. 
A  better  interpretation,  however,  seems  to  be  found  in  attributing  the  upper 
gravel  to  the  highest  fluctuation  of  the  lake  when  raised  several  feet  by  the 
rapid  glacial  melting  in  the  summer,  the  till  below  having  been  cut  away 
by  the  reduced  water  level  in  the  winters,  when  it  was  lashed  into  powerful 
waves  by  storms. 

But  a  large  share  of  the  erosion  of  the  less  steep  lower  slope  was  done 
by  the  lake  during  the  lower  Ojata  stage.  In  the  latest  and  lowest  portion 
of  that  stage  there  was  also  formed  a  discontinuous  beach  ridge  of  gravel 
and  sand,  which  lies  in  isolated,  irregular  accumulations  a  half  mile  east  of 
the  escarpment,  and  rises  6  to  8  feet  above  the  flat  expanse  on  each  side, 
with  crests  at  870  feet,  approximately.  This  fragmentary  beach  divides  a 
tract  of  till  on  the  west  which  has  suifered  much  erosion  of  its  surface,  being 
therefore  strewn  with  frequent  or  abundant  bowlders,  from  another  tract  on 
the  east,  where  the  upper  pai't  of  the  till  to  the  depth  of  5  to  10  feet  or  more, 
still  lying  as  it  was  deposited  in  Lake  Agassiz,  bears  marks  of  imperfect 
stratification,  and  has  fewer  bowlders  and  less  gravel  on  the  surface  than  at 
a  slight  depth.  Within  10  to  15  feet  beneath  the  surface,  as  shown  by 
wells  and  the  ravines  of  streams  in  the  neighborhood  of  Ojata,  the  lacus- 
trinely  modified  till,  which  was  englacial,  is  succeeded  below  by  the  wholly 
unstratified  ground  moraine.  It  is  also  to  be  noted  that  a  thin  layer  of 
lacustrine  clayey  sand  and  fine  silt,  doubtless  derived  chiefly  from  the  ero- 
sion of  the  escarpment  on  the  west,  is  spread  with  a  thickness  varying  from 
a  few  inches  to  a  few  feet  on  much  of  the  sui'face  eastward  from  the  lower 
Ojata  beach. 

Ten  to  15  miles  northwest  of  Ojata  the  upper  one  of  these  two  shore- 
lines is  well-marked  in  Gilby  by  a  typical  beach  ridge  of  gravel  and  sand, 
lying  on  or  near  the  eastern  limit  of  the  till,  beyond  which  lacustrine  and 
alluvial  silt  stretch  east  to  the  Red  River.  Mr.  John  Gilby's  house,  in  the 
southwest  quarter  of  section  22,  is  built  on  the  gravel  beach,  which  thence 


462  THE  GLACIAL  LAKE  AGASSIZ. 

runs  north-northwestward  through  the  middle  of  section  9,  a  half  mile  east 
of  Gilby  station,  on  the  Duluth  and  Manitoba  Railroad.  The  lower  Ojata 
shore  lies  about  a  mile  farther  east,  but  was  not  examined.  The  upper 
shore  extends  from  section  4,  Gilby,  into  the  southwest  quarter  of  section 
33,  Milan,  being  there  an  escarpment  5  feet  high,  eroded  on  an  area  of  fine 
silt.  Its  base  and  crest  are  approximately  870  and  875  feet  above  the  sea. 
This  shore  passes  about  a  mile  west  of  Jolmstown,  and  the  lower  shore  lies 
close  east  of  that  railroad  station. 

A  conspicuous  beach  ridge  of  gravel  and  sand,  running  nearlj^  along 
the  boundary  between  till  on  the  west  and  silt  on  all  the  country  eastward, 
extends  from  the  west  half  of  section  36,  in  an  almost  straight  course,  a  few 
degrees  west  of  north,  5  miles  to  the  northwest  corner  of  section  2,  Ops, 
having  an  elevation  at  its  crest  of  875  to  880  feet,  with  descent  of  5  to  10 
feet  east  and  2  to  5  feet  west.  A  mile  farther  east  a  smaller  ridge,  about 
10  feet  lower,  marks  the  second  Ojata  shore.  Tlnrough  the  remaining  50 
miles  of  its  course  northward  to  the  international  boundary  the  upper 
shore-line  is  mapped  approximately  on  Pl.  XXX,  conforming  with  the  east- 
ward descent  of  the  land  surface.  It  will  probably  be  found  easily  trace- 
able if  followed  by  leveling. 

Along  the  course  of  the  Ojata  shores,  lying  between  the  Emerado  and 
Gladstone  beaches,  no  ridge  of  gravel  and  sand  nor  line  of  erosion  was 
observed  where  they  were  crossed  on  the  international  boundary  and  else- 
where during  my  exploration  in  Manitoba,  excepting  a  slight  beach  ridge, 
3  to  5  feet  high,  which  runs  from  Pomeroy,  in  section  19,  township  5,  range 
4,  north-northwest  through  the  east  part  of  townsliip  6,  range  5,  passing 
about  2  miles  west  of  Carman. 

Mr.  Tyi-rell  notes  the  lower  Ojata  beach  on  Kettle  Hill,  if  my  correla- 
tion is  true,  at  the  elevation  of  955  feet  above  the  sea. 

THE   GLADSTONE    BEACH. 

The  extent  of  the  southern  part  of  Lake  Agassiz  at  the  time  of  for- 
mation of  the  Gladstone  beach  is  shown  approximately  on  PI.  XXXVI. 

Crossing  the  Red  River  near  Belmont,  N.  Dak.,  about  20  miles  south 
of  Grand  Forks,  at  a  height  approximately  845  feet  above  the  sea,  the 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH   XXV.    PL.    XXXVL 


MAP  OF  THE    SOUTHERN  PORTION  OF  LAI\E  AGASSIZ,  SHOWING  ITS  EXTENT  IN  THE 

GLADSTONE    STAGE. 
Scale ,  abimt  h2  rniles  to  iis\  inch . 


THE  GLADSTONE  BEACH.  463 

Gladstone  shore-Hue  runs  northward  through  Minnesota,  mostly  at  a  dis- 
tance of  about  15  miles  east  of  the  Red  River.  It  crosses  the  Red  Lake 
River  near  the  head  of  the  Grand  Marais,  about  a  mile  northwest  of  Fisher. 

Thence  northward  for  a  distance  of  more  than  25  miles  to  Warren 
there  is  frequently  found  along  the  contour  line  of  840  feet  a  somewhat 
more  rapid  descent  from  east  to  west  than  on  the  adjoining  surface  of  fine 
clayey  silt  at  each  side.  This  may  be  due  mainly  to  erosion  by  the  waves 
of  gi'eat  storms,  especially  when  the  lake  surface  was  lowered  a  few  feet 
on  account  of  the  diminished  rate  of  melting  of  the  ice-sheet  during  win- 
ters. In  part,  however,  there  appears  to  have  been  formed  along  this 
course  an  oftshoi'e  deposit  several  feet  thick,  rising  nearly  to  the  lake  level. 
Such  a  broad  ridge,  with  crest  at  838  to  841  feet,  runs  northward  through 
the  center  of  section  15  and  the  west  half  of  section  10,  Tabor,  having  a 
descent  of  1  to  3  feet  eastward  and  of  3  to  5  feet  westward  within  a  third 
of  a  mile  from  its  top.  Wells  on  this  swell  obtain  good  water  at  the 
depth  of  10  to  12  feet,  in  layers  of  sand  from  a  quarter  of  an  inch  to  1 
foot  thick,  inclosed  in  the  fine  stratified  silt  which,  excepting  these  sandy 
beds,  is  almost  impervious  to  water. 

In  the  northern  part  of  Kittson  County  the  old  St.  Paul  trail,  lying  12 
to  14  miles  east  of  the  Red  River,  ran  for  6  miles  south-southeastward  from 
the  international  boundary  on  and  near  to  the  Gladstone  beach,  whose  crest 
there  has  a  height  of  858  to  863  feet  above  the  sea.  It  is  a  ridge  of  gravel 
and  sand  10  to  30  rods  wide,  resting  on  till,  to  which  its  eastern  slope  falls 
2  to  3  feet  and  its  western  slope  5  to  8  feet. 

Through  North  Dakota  the  Gladstone  shore  has  been  mapped  approx- 
imately, passing  from  Belmont  north-northwesterly  by  Merrifield,  Kelleys, 
and  Voss,  lying  about  4  miles  west  of  Grafton,  2  to  3  miles  west  of  Auburn, 
St.  Thomas,  and  Glasston,  about  4  miles  west  of  Hamilton  and  Bathgate, 
and  5  miles  west  of  Neclie.  In  this  distance  of  100  miles  the  shore  rises 
from  845  to  857  feet,  approximately,  above  the  sea.  Only  small  portions 
of  its  course  have  been  examined,  these  near  Merrifield  and  2  miles  east  of 
Ojata  being  marked  by  slight  erosion  in  the  lacustrine  and  alluvial  silt  over 
which  it    asses. 


464  THE  GLACIAL  LAKE  AGASSIZ. 

On  the  international  boundary  and  for  several  miles  thence  to  the 
north-northwest  the  Gladstone  beach  is  a  prominent  ridge,  having  an 
ascent  of  10  to  15  feet  in  a  distance  of  30  to  50  rods  west  from  its  base  to 
its  crest,  which  is  approximately  860  feet  above  the  sea.  The  slightly 
undulating  surface  of  this  shore  deposit  occupies  a  width  of  a  quarter  of 
a  mile  or  more,  and  thence  westward  there  is  no  noteworthy  descent,  but  a 
nearly  level  expanse.  In  many  shallow  pits  dug  to  obtain  sand  for  masons' 
use  the  material  of  the  beach  is  shown  to  be  fine  sand,  unmixed  with 
gravel,  excepting  that  very  rarely  a  pebble  is  found  inclosed  in  it,  the 
largest  being  a  half  to  two-thirds  of  an  inch  in  diameter.  This  ridge 
enters  Manitoba  about  IJ  miles  west  of  Blumenort,  and  crosses  sections 
5,  7,  and  18,  township  1,  range  2,  to  Kronsthal,  which  is  situated  upon 
it.  Northward  it  jjasses  about  a  mile  west  of  Lowestoft  post-office  and  a 
mile  east  of  Carman.  George  Anderson's  house  is  built  on  its  crest  in 
the  northeast  quarter  of  section  31,  township  6,  range  4,  2  miles  north- 
northeast  of  Carman,  at  an  elevation  of  865  feet.  It  crosses  the  Canadian 
Pacific  Railway  near  the  Rat  Creek  bridge,  and  is  well  developed  along  a 
distance  of  several  miles  thence  to  the  northwest,  passing  through  the 
southeast  corner  of  section  12,  township  12,  range  9,  where  the  elevation 
of  its  crest  is  about  875  feet,  with  a  descent  of  4  to  6  feet  to  the  northeast 
and  1  to  3  feet  to  the  southwest.  Thence  its  course  is  along  the  southwest 
side  of  the  Squirrel  Creek  marsh  and  east  of  the  chain  of  Dead  Lakes  (a 
former  channel  of  the  White  Mud  River),  which  lie  in  sections  17,  18,  and 
19,  township  14,  range  11.  A  half  mile  east  of  Gladstone  this  shore  is 
marked  by  a  line  of  erosion  in  the  expanse  of  lacustrine  silt,  with  slope 
from  882  to  875  feet  in  a  short  distance,  and  by  a  small  beach  ridge  of 
sand  with  its  crest  at  878  feet.  Continuing  almost  due  noi-tli,  this  Glad- 
stone shore-line,  occasionally  marked  by  beach  gravel  and  sand,  lies  a  half 
mile  to  1  mile  west  of  the  Big  Grass  Mai-sh,  thi-ough  townships  15,  16,  and 
17,  range  11,  the  elevation  of  the  marsh  being,  approximately,  865  feet, 
and  of  Lake  Agassiz  here  during  this  stage  about  875  feet  above  the 
present  sea-level. 

The  Gladstone  beach  is  noted  by  Mr.  Tyrrell  on  Kettle  Hill  at  920 
feet.     Combined  differential  uplifting  of  the  land  and  depression  of  the 


GLADSTONE  AND  BUENSIDE  BEACHES.  465 

geoid  siu'face  of  level,  both  due  to  removal  of  the  ice-sheet,  have  amounted 
to  about  45  feet  in  the  distance  of  150  miles  northward  from  Gladstone  to 
this  locality. 

THE  BUENSIDB  BEACH. 

From  its  crossing-  of  the  Red  River  at  Grand  Forks  the  Burnside  shore 
in  Minnesota  runs  northeastward  to  the  southwest  corner  of  Tabor  Town- 
ship, and  thence  northward  at  a  distance  of  10  to  13  miles  from  the  river 
for  about  70  miles  to  the  south  line  of  Manitoba.  Although  its  course  is 
known  approxinaately  by  the  Drainage  Survey  and  by  railway  leveling,  no 
portions  of  it  distinctly  showing  marks  of  erosion  or  beach  accumulation 
have  been  observed  in  this  State  excepting  close  upon  the  international 
boiindary.  There  it  is  found  at  "the  Ridge,"  about  11  miles  east  of  the 
Red  River  and  Emerson,  which  is  a  low,  eroded  escaii^ment  extending 
from  south  to  north  across  the  boundary.  It  consists  of  till  with  frequent 
bowlders,  nearly  all  Archean  granites,  gneiss,  and  schists.  A  deposit  of 
beach  gravel  and  sand  a  few  feet  deep  rests  on  the  base  of  this  slope,  835 
to  840  feet  above  the  sea. 

Two  miles  northward,  in  the  southwest  quarter  of  section  15,  town- 
ship 1 ,  range  4  east,  Manitoba,  the  Burnside  beach  is  a  typical  gravel  and 
sand  ridge  20  to  25  rods  wide;  its  crest  is  845  feet  above  the  sea,  and  the 
descent  from  it  to  the  east  is  about  3  feet  and  to  the  west  6  or  7  feet. 
About  a  mile  farther  north,  near  the  southeast  comer  of  section  21,  the 
elevation  of  this  beach  ridge  is  844  feet,  with  a  descent  of  1  or  2  feet  on 
the  east  and  10  feet  within  20  rods  on  the  west.  Another  mile  to  the  north 
its  elevation  is  846  feet,  with  2  feet  descent  east  and  6  feet  west  in  6  rods; 
next  a  sin-face  of  till,  with  many  bowlders,  falls  about  5  feet  in  40  rods  to 
the  west;  beyond  this  a  tract  of  gravel  and  sand  continues  with  the  same 
slope,  falling  from  835  to  830  feet,  and  is  succeeded  farther  west  by  a 
slowly  descending  surface  of  till.  The  beach  ridge  continues  with  similar 
features  through  the  east  half  of  section  28,  excepting  a  short  distance 
in  the  southeast  quarter  of  this  section,  where  it  is  replaced  by  a  line  of 
erosion  in  the  very  rocky  till.  Through  the  next  3  miles  the  uneven  con- 
tour causes  the  beach  ridge  to  he  somewhat  irregular  in  its  course  and  size; 
but  it  again  attains  its  typical  development  in  section  9,  township  2,  range 
MON  XXV 30 


466  THE  GLACIAL  LAKE  AGASSIZ. 

4  east,  where  it  was  excavated  several  years  ago  aloug  a  distance  of  a  third 
of  a  mile  for  railway  ballast,  a  branch  track  nearly  8  miles  long  being  laid 
for  its  transportation  to  Dominion  City.  The  crest  of  the  beach  at  Charles 
Aime's  house,  near  the  north  end  of  this  excavation,  is  846  to  847  feet 
above  the  sea,  with  a  descent  of  2  to  5  feet  on  the  east  and  6  to  8  feet  in 
8  to  12  rods  west.  Its  width,  including  both  slopes,  is  16  to  30  rods,  and 
the  maxinmm  depth  of  the  gravel  and  sand  deposit  is  about  8  feet,  lying 
on  till.  The  coarser  portions  of  the  gravel  contain  pebbles  up  to  3  inches 
or  rarely  6  inches  or  more  in  diameter.  Nine-tenths  or  a  larger  propor- 
tion of  them  are  magnesian  limestone,  the  remainder  being  almost  wholly 
Archean  granite  and  gneiss.  This  shore-line  continues  north  and  north- 
northeast  by  Green  Ridge  post-office  and  through  the  east  part  of  townships 
3  and  4,  range  4  east,  beyond  which  it  has  not  been  traced. 

In  North  Dakota  the  course  of  the  Burnside  shore  is  known  somewhat 
nearly  and  has  been  di-awn  provisionally  on  Pis.  XXIX  and  XXX,  in 
accordance  with  the  elevations  ascertained  by  railway  surveys;  but,  as 
in  Minnesota,  no  part  of  it  has  been  observed  to  be  clearly  traceable  by 
either  a  continuous  beach  ridge  or  an  eroded  escarpment.  It  lies  on  the 
wide,  flat  tract  of  silt  which  adjoins  the  Red  River,  a  surface  most  unfavor- 
able for  the  preservation  of  definite  shore-lines;  yet  undoubtedly  it  can  be 
found  and  followed  by  careful  search  with  leveling. 

A  few  feet  below  the  average  Bm-nside  level  of  Lake  Agassiz  marks 
of  wave  action,  perhaps  belonging  to  the  lowest  fluctuations  of  the  lake  in 
this  stage,  are  somewhat  indistinctly  exhibited  by  an  irregularly  ridged 
contour  which  was  seen  near  Schurmeier  and  along  the  east  side  of  the  rail- 
way thence  northwestward  to  Manvel,  also  in  the  west  edge  of  Manvel 
village.  These  swells,  extending  parallel  with  the  railway,  rise  2  to  3 
feet  above  the  depressions  on  either  side,  their  crests  being  820  to  825  feet 
above  the  sea.  Proceeding  northwest  along  the  railway,  which  holds  a 
nearly  level  grade,  no  further  noteworthy  observations  of  this  kind  were 
obtained  for  the  next  12  miles  to  Ardoch,  where  again  a  beach-like  swell 
or  very  low  ridge,  2  to  3  feet  high  and  having  a  Avidth  of  30  rods  or  more, 
with  crest  at  826  to  827  feet,  runs  from  south  to  north  across  the  railway 
about  an  eighth  of  a  mile  north  of  the  station. 


THE  BUENSIDE  BEACH  IN  MANITOBA.  467 

This  western  Burnside  shore  enters  Manitoba  near  Blumenort,  19  miles 
west  of  the  Red  River,  but  it  is  not  distinctly  marked  on  the  international 
boundary.  Passing  northward  about  a  mile  east  of  Lowestoft  and  3  miles 
east  of  Cannan,  it  crosses  the  Carman  Branch  of  the  Manitoba  and  South- 
western Railway  at  Maryland,  where  the  elevation  of  the  crest  of  its  beach 
ridge  is  844  feet.  About  a  mile  north-northwest  of  Maryland  this  ridge 
has  been  extensively  excavated,  its  gravel  and  sand  being  used  for  railway 
ballast.  One  and  a  half  miles  farther  north  it  crosses  the  main  line  of 
this  railway  about  a  mile  west  of  Elm  Creek  station  (the  junction  of  the 
branch),  its  crest  there  being  at  845  feet,  from  which  its  slopes  fall  10  feet 
in  25  rods  east  and  7  feet  in  an  equal  distance  west. 

The  Canadian  Pacific  Railway  crosses  this  shore  about  halfway  be- 
tween Portage  la  Prairie  and  Burnside,  and  in  the  next  1(J  miles  of  its 
course,  passing  northwest  nearly  thi'ough  the  center  of  township  12,  range 
8,  it  is  marked  by  a  large  gravel  ridge,  the  crest  of  which,  in  the  south  part 
of  section  11,  IJ  to  2  miles  north  of  Burnside,  has  an  elevation  of  858  to 
860  feet,  with  descent  from  it  of  6  to  10  feet  northeastward  and  half  as 
much  to  the  southwest.  This  beach  is  similarly  prominent  on  the  Manitoba 
and  Northwestern  Railway,  by  which  it  is  crossed  and  excavated  for  ballast 
halfway  between  Westbourne  and  Woodside,  its  crest  there  being  860  to 
862  feet  above  the  sea.  Along  the  next  40  miles  the  Burnside  shore-line  is 
generally  mai'ked  by  a  well-developed  beach  ridge  which  is  traceable  on 
the  plats  of"  the  Dominion  Land  Sui-veys  parallel  with  the  west  shore  of 
Lake  Manitoba  and  4  to  5  miles  distant  from,  it,  passing  about  halfway 
between  the  lak-e  and  the  Big  Grrass  Marsh.  It  thus  lies  near  the  line 
between  ransres  9  and  10  as  far  north  as  to  the  east  side  of  the  lake  in 
sections  13  and  24,  township  18,  range  10,  beyond  which  it  runs  north- 
northwest. 

Between  the  south  ends  of  Lakes  Manitoba  and  Winnipeg  the  country 
about  Shoal  Lake  was  uncovered  by  the  fall  of  Lake  Agassiz  from  the 
Gladstone  to  the  Burnside  beach,  which  latter  is  crossed  by  the  Winnipeg 
and  Hudson  Bay  Railway  near  the  southwest  corner  of  section  36,  town- 
ship 14,  range  2,  about  3  miles  south  of  Shoal  Lake.  The  crest  of  the 
beach  is  860  feet  above  the  sea,  being  10  feet  above  Shoal  Lake.     Here  its 


468  THE  GLACIAL  LAKE  AGASSIZ. 

course  is  from  west  to  east  along  the  verge  of  a  nearly  level  expanse  of 
till  reaching  to  the  lake,  to  which  its  drainage  is  tributary.  Two  or  3  miles 
farther  east,  where  the  road  to  Stonewall  and  Winnipeg  crosses  this  beach, 
it  has  a  descent  of  20  feet  in  30  or  40  rods  south  from  its  crest,  the  whole 
slope  being  gravel  and  sand,  the  combined  shore  deposits  of  the  Bumside 
and  Ossowa  stages  of  Lake  Agassiz.  Westward  the  beaches  of  these  stages 
are  separated  by  a  width  of  1  to  2  miles,  the  Burnside  beach  lainning 
southwest  and  west  tlu-ough  the  south  half  of  township  14,  rang-e  3.  Near 
the  west  side  of  this  township  it  curves  northward,  and  thence  passes  north 
and  north-northwest  between  Shoal  and  Manitoba  lakes.  East  of  the  road 
before  mentioned  the  course  of  this  beach  is  northeastward  across  town- 
ship 15,  range  1  east,  and  township  16,  range  2  east,  to  Pleasant  Home 
post-office.  Numerous  short  beach  ridges  noted  on  the  township  plats 
northwest  of  this  beach,  between  it  and  Shoal  Lake,  were  probably  formed 
during  the  Gladstone  stage  of  Lake  Agassiz  where  the  highest  parts  of  that 
area  rose  above  its  level. 

Passing  over  the  eastern  Mossy  portage  from  Lake  Winnipegosis  to 
Cedar  Lake,  on  the  Saskatchewan,  Mr.  Tyrrell  found  that  the  highest  land 
crossed  is  a  gravel  ridge  with  crest  921  feet  above  the  sea,  being  93  feet 
above  the  first  of  these  lakes.  It  probably  is  a  beach  belonging  to  a  level 
of  Lake  Agassiz  near  910  feet,  the  same  stage  that  formed  the  Burnside 
shore-line  farther  south.  This  locality  is  about  70  miles  northeast  of 
Kettle  Hill,  and  the  continuation  of  the  Gladstone  beach  with  the  gradient 
which  it  has  from  Gladstone  to  Kettle  Hill  would  cany  it  at  Mossy  portage 
85  or  40  feet  above  the  Bm-nside  level  there. 

THE    OSSOWA    BEACH. 

Lake  Agassiz  at  the  time  of  the  Ossowa  beach  extended  into  the 
United  States  nearly  60  miles,  but  the  only  part  of  this  shore  which  has 
been  recognized  and  examined  south  of  the  international  boundary  is  an 
extent  of  a  few  miles  in  Pembina  County,  N.  Dak.  In  sections  21,  16, 
and  17,  township  162,  range  52,  close  south  of  the  Tongue  River,  at  a 
distance  of  4  miles  northeast  from  Hamilton,  two  or  thi'ee  parallel  low, 


THE  OSSOWA  BEACH.  469 

beach-like  ridges  were  observed,  elevated  2  to  4  feet  above  the  intervening 
hollows  and  general  surface,  their  height  being  between  815  and  820  feet 
above  the  sea.  They  run  from  southeast  to  northwest,  and  their  continu- 
ation north  of  this  river  was  noted  at  the  same  height  4  to  6  miles  north- 
westward in  sections  36  and  25,  Neche,  about  2J  miles  east-northeast  from 
Bathgate.     Both  the  ridges  and  the  adjoining  surface  are  fine  silt. 

Ossowa  post-office,  from  which  the  shore-line  takes  its  name,  is  situated 
near  the  middle  of  the  north  half  of  section  27,  township  13,  range  4, 
Manitoba,  on  a  well-defined  beach  ridge  which  runs  from  west-southwest 
to  east-northeast  through  this  township.  Its  crest  varies  in  elevation  from 
843  to  848  feet,  with  descent  of  3  to  8  feet  on  its  north  side  and  12  to  15 
feet  on  the  south.  The  Canadian  Pacific  Railway  was  originally  con- 
structed from  Stonewall  due  west  to  this  beach,  which  it  cut  through  in  the 
east  edge  of  section  28.  In  the  railway  cut  its  material  is  wholly  gravel, 
in  part  very  coarse,  containing  pebbles  and  subangular  rock  fragments  up 
to  4  inches  and  rarely  6  or  8  inches  in  diameter,  of  which  fully  nineteen- 
twentieths  are  magnesian  limestone.  On  each  side  the  surface  is  till,  with 
plentiful  bowlders,  mostly  Archean  granite  and  gneiss,  but  including  many 
of  this  limestone,  which  is  the  underlying  rock  of  the  region.  In  the 
north  part  of  township  13,  range  3,  this  beach  curves  to  the  south,  east, 
and  northeast,  and  thence  passes  through  the  southeast  part  of  town- 
ship 14,  range  3,  and  the  north  half  of  township  14,  range  2,  gradually 
approaching  and  in  some  places  joining  the  Burnside  beach,  with  which 
the  Ossowa  beach  is  approximately  parallel,  lying  a  half  mile  to  1  or  2 
miles  southeast  of  it  onward  to  Pleasant  Home. 

The  only  other  locality  where  a  beach  referable  to  this  stage  was 
observed  is  on  the  top  of  Stony  Mountain,  on  which  a  broad,  smoothly 
rounded  ridge  of  gravel  and  sand  extends  nearly  a  quarter  of  a  mile,  and 
is  the  site  of  some  of  the  penitentiary  buildings.  Its  crest  is  about  835 
feet  above  the  sea,  and  the  top  of  the  underlying  limestone  about  825  feet. 

The  western  Ossowa  shore-line  crosses  the  international  boundary  3 
or  4  miles  east  of  Gretna,  and  the  eastern  enters  Minnesota  about  three- 
quarters  of  a  mile  west  of  "the  Ridge,"  but  they  are  not  there  marked  by 
noteworthy  beach  deposits  nor  erosion. 


470  THE  GLACIAL  LAKE  AGASSIZ. 

North  of  Lake  Winnipegosis,  tlie  Ossowa  shore  on  the  ascent  of  the 
eastern  Mossy  portage,  as  described  by  Mr.  Tyrrell,  takes  the  form  of  an 
escai-pment,  with  its  crest  63  feet  above  this  lake,  or  891  feet  above  the  sea. 
It  was  probably  eroded  by  the  waves  of  Lake  Agassiz  when  its  surface 
there  was  approximately  at  875  feet,  midway  between  its  Burnside  and 
Stonewall  levels  at  this  locality. 

THE   STONEWALL  BEACH. 

In  the  town  of  Stonewall,  Manitoba,  the  main  street  crosses  a  conspic- 
uous beach  ridge  which  runs  from  south-southwest  to  north-northeast  a 
third  of  a  mile  or  more.  Its  crest  is  820  to  825  feet  above  the  sea,  and  its 
depth  is  about  10  feet.  Only  2  or  3  feet  of  till  intervene  between  this 
gravel  and  sand  and  the  underlying  limestone,  which,  thinly  covered  by 
drift,  rises  in  a  swell  here  about  25  feet  above  the  adjoining  country  a  half 
mile  distant  to  the  east  and  west.  Beach  deposits  belonging  to  this  stage 
were  not  elsewhere  observed  in  southern  Manitoba,  but  they  are  doubtless 
traceable  from  Stonewall  northward  through  the  west  half  of  townships  14 
and  15,  range  2  east.  Lake  Agassiz,  at  the  time  of  the  Stonew;an  beach, 
probably  extended  on  the  flat  Red  River  Valley  to  a  distance  of  about 
25  miles  south  of  the  international  boundary,  being  some  15  feet  deep  at 
Emerson,  St.  Vincent,  and  Pembina,  while  over  the  site  of  Winnipeg  its 
depth  was  about  60  feet. 

A  somewhat  ridged  eontoiir  upon  the  otherwise  very  flat  surface  of  fine 
alluvial  silt  was  noted  6  to  7  miles  east  of  Hamilton  and  Bathgate,  N.  Dak. 
The  wave-like  and  almost  beach-like  undulations,  rising  2  to  4  feet  above 
the  depressions  which  separate  them  and  above  the  general  level,  run  north- 
northwesterly  through  the  east  part  of  section  11  and  the  central  part  of 
section  2,  township  162,  range  52,  close  southeast  of  the  Tongue  River. 
Similar  ccmtour  was  also  noticed  in  the  continuation  of  this  course  within  a 
few  miles  northward  between  the  Tongue  and  Pembina  rivers.  The  height 
of  this  belt  is  about  805  feet  above  the  sea. 

On  the  eastern  Mossj^  portage  the  crest  of  the  Stonewall  beach,  as 
observed  by  Mr.  Tyrrell,  is  27  feet  above  Lake  Winnipegosis,  or  855  feet 


STONEWALL  AND  NIVEEVILLE  BEACHES.  471 

above  the  sea,  being  probably  10  feet  higher  than  the  level  of  Lake  Agassiz 
there  when  the  beach  was  accumulated.  Again,  on  the  line  of  the  tramway 
at  the  Grand  Rapids  of  the  Saskatchewan,  the  same  beach  is  found  by  Mr. 
Tyrrell  at  the  elevation  of  850  feet;  and  he  states  that  it  is  also  well  seen 
at  Point  Brabant  and  other  places  along  the  east  side  of  Lake  Winnipegosis, 
and  that  it  probably  is  represented  by  the  ridge  in  the  grove  behind  Mani- 
toba House,  which  is  situated  on  the  west  shore  of  Lake  Manitoba,  close 
south  of  the  Narrows. 

BEACHES  OF  THE  NIVERVILLE  STAGES. 

The  road  on  the  east  side  of  the  Red  River  between  Winnipeg  and 
Emerson  crosses  a  beach  ridge  about  a  half  mile  southeast  of  Niverville. 
It  has  a  width  of  15  rods,  and  its  crest,  777  to  778  feet  above  the  sea,  is 
raised  about  4  feet  above  the  adjoining  surface  of  lacustrine  silt  on  each 
side.  Beginning  near  Niverville  station,  it  extends  southeasterly  at  least  a 
mile.  Another  beach  ridge  of  similar  size,  with  its  crest  at  780  feet,  is 
crossed  by  this  road  a  third  of  a  mile  farther  south.  This  also  runs 
southeast,  holding  its  ridged  form  a  mile  or  more,  beyond  which  it  is  less 
distinct.  Again,  a  few  miles  to  the  south  from  these,  a  beach  ridge  extends 
along  this  road  in  a  nearly  due-south  course  across  the  southeast  quarter  of 
section  17  and  the  east  half  of  sections  8  and  5,  townshijj  7,  range  4  east. 
It  rises  2  to  4  feet  above  the  land  adjoining  on  each  side,  which  is  partly 
sloughs,  with  water  throughout  the  year,  the  elevation  of  the  beach  crest 
being  782  to  784  feet.  Other  beach  deposits  at  nearly  the  same  elevation 
occur  a  mile  southwest  of  Otterburne;  a  few  miles  farther  to  the  south  in 
the  northeast  part  of  township  5,  range  3  east;  and  about  a  mile  east  of  the 
Red  Rivei',  opposite  to  Morris.  At  the  last-named  locality  thej  are  exca- 
vated for  masons'  sand.  From  the  southern  end  of  Lake  Agassiz  in  this 
stage,  near  Morris,  Manitoba,  its  western  shore  extended  north  and  north- 
west to  the  vicinity  of  Starbuck,  thence  north  and  northeast  to  Little  Stony 
Mountain,  5  miles  northwest  of  Winnipeg,  and  thence  niearly  due  north, 
passing  between  Stonewall  and  Stony  Mountain  and  onward  along  the  west 
side  of  Lake  Winnipeg,  at  a  distance  of  a  few  miles  from  it.     Gravelly  and 


472  THE  GLACIAL  LAKE  AGASSIZ. 

sandy  deposits  at  the  base  of  Stony  Mountain  on  its  nortli  and  south  sides 
are  attributable  to  erosion  by  the  lake,  there  only  a  few  feet  deep,  at  the 
time  of  formation  of  the  Niverville  beach.  Its  level  was  15  to  20  feet 
above  the  surface  where  the  city  of  Winnipeg  is  built. 

Numerous  observations  of  the  Niverville  beach  have  been  made  by 
Mr.  Tyrrell  on  the  shores  and  islands  of  Lake  Winnipeg.  Its  occurrence 
on  Black  Island,  about  150  miles  north  of  the  international  boundary,  is 
described  by  him  as  follows,  excepting  that  his  later  determination  of  the 
height  of  the  beach  as  60  feet  above  Lake  Winnipeg  is  substituted  instead 
of  his  previous  estimate,  which  was  20  feet  lower: 

At  Ox  Head,  uear  the  northeastern  extremity  of  Black  Island,  an  ancient  beach 
is  very  conspicuous  at  about  60  feet  above  the  water.  On  the  south  side  of  the  island 
the  beach  is  marked  by  a  line  of  sand  dunes,  and  on  the  north  side  a  sandy  terrace 
rises  gently  to  a  height  of  60  feet  and  ends  abruptly  at  the  foot  of  a  steep  slope  thickly 
strewn  with  bowlders.  On  ascending  this  slope  the  land  is  found  to  rise  to  a  height 
of  100  feet  above  the  lake  and  its  summit  to  consist  of  an  irregular  aggregation  of 
knolls,  thickly  strewn  with  large  bowlders  of  gneiss,  very  few  or  none  being  derived 
from  the  immediately  adjoining  or  underlying  Keewatin  schists.  This  ridge  is  the 
summit  of  the  Black  Island  moraine,  which  would  seem  to  have  been  dropped  here 
when  the  higher  parts  of  the  island  were  above  the  surface  of  Lake  Agassiz,  as  there 
is  no  sign  of  water  action  on  the  moraine  above  the  line  of  the  60-foot  beach.  It  is 
possible  that  the  moraine  may  have  been  deposited  about  the  water  level,  and  that  the 
water  afterwards  rapidly  receded  to  a  height  60  feet  above  the  present  lake.  ^ 

Instead  of  the  view  taken  by  Mr.  Tyi-rell,  however,  concerning  the 
depth  of  Lake  Agassiz  here  when  the  Black  Island  moraine  was  formed,  I 
believe  that  it  was  deposited  in  water  600  to  700  feet  deep,  bordering  the 
ice  front,  contemporaneously  with  the  foi-mation  of  the  Herman  or  Norcross 
shore-Hnes.  The  morainic  accumulations,  lying  thenceforward  at  the  bot- 
tom of  Lake  Agassiz,  could  not  have  been  exposed  to  erosion  by  its  waves 
until  the  very  late  change  of  its  northward  outlets,  by  which  the  lake  fell 
about  50  feet  between  the  Stonewall  and  Niverville  beaches;  and  this 
reduction  appears  to  have  taken  place  so  quickly  that  no  beach  ridge  nor 
eroded  escarpment  was  made  on  the  upper  part  of  Black  Island. 

At  the  Grand  Rapids  of  the  Saskatchewan,  according  to  Mr.  Tyrrell, 
the  tramway  of  the  portage,  which  is  some  4  miles  from  the  mouth  of  the 

'  Am.  Geologist,  Vol.  VIII,  p.  25,  July,  1891. 


NIVEEVILLE  BEACHES.  473 

nver  and  extends  about  1  mile,  crosses  three  beach  ridges  of  gravel  and  sand 
that  together  represent  the  single  Niverville  beach  farther  south.  Their 
heights,  in  order  from  west  to  east,  are  95,  90,  and  80  feet  above  Lake 
Winnipeg,  or  805,  800,  and  790  feet  above  the  sea.  Two  Niverville  stages 
of  Lake  Agassiz,  or  we  may  say  three,  are  thus  shown  to  have  been  caused 
here  by  the  northward  uplifting  of  the  land,  with  intervals  of  5  and  10  feet 
between  its  stages  of  temporary  repose. 

All  the  shore-lines  described  in  this  chapter  and  in  the  two  preceding 
chapters  must  be  referred  to  the  glacial  Lake  Agassiz,  held  on  its  northern 
side  by  the  barrier  of  the  waning  ice-sheet;  for  the  country  north  of  Lake 
Winnipeg  presents  no  barrier  of  land  through  which  the  Nelson  River  has 
cut  its  passage  so  high  as  the  Niverville  beach.  Lake  Winnipeg  and  its 
outflowing  stream  have  been  lowered  by  erosion  only  about  20  feet  from 
the  level  of  the  beach  noted  by  Hind  thirty -five  years  ago.^ 

See  Cha  ter  V,  p.  221. 


CHAPTER  IX. 
CHANGES  IN  THE  LEVELS  OF  THE  BEACHES. 

THE  NORTHWARD   ASCENT   OF   THE   WESTERN   SHORE-LINES. 

The  successive  shore-lines  of  Lake  Agassiz  are  not  parallel  with  each 
other  and  with  the  present  levels  of  the  sea  and  of  Lakes  Winnipeg  and 
Manitoba,  but  have  a  gradual  ascent  from  south  to  north,  which  is  greatest 
in  the  earlier  and  higher  beaches  and  slowly  diminishes  through  the  lower 
stages  of  the  lake,  being  at  last  only  slightly  different  from  the  level  of 
the  j^resent  time.  On  the  west  side  of  Lake  Agassiz  the  elevations  of  its 
beaches  have  been  determined  by  my  continuous  leveling,  referred  to  sea- 
level  by  railway  surveys,  through  a  distance  of  more  than  300  miles  from 
its  mouth  at  Lake  Traverse  northward  to  near  Riding  Mountain  in  Mani- 
toba; and  the  accompanying  table,  on  page  476,  shows  approximately  the 
stages  of  the  lake  during  the  formation  of  these  shore-lines  in  their  rela- 
tions to  each  other  and  to  the  present  level.  These  stages  of  the  water 
surface  have  been  assumed  to  coincide  generally  with  the  foot  of  the  lake- 
ward  slope  of  the  beach  ridges,  and  with  the  base  of  the  eroded  shore 
escarpments,  the  crests  of  the  beaches  having  had  a  variable  height  from 
5  to  15  feet  above  the  lake,  corresponding  with  their  less  or  more  massive 
development,  while  the  escarpments  rose  from  the  water's  edge  10,  20,  or 
rarely  30  feet. 

In  this  table  the  estimated  stages  of  the  lake  are  noted  for  comparison 
at  its  mouth,  where  it  outflowed  l)y  the  River  Warren  at  the  north  end  of 
Lake  Traverse,  and  on  four  lines  of  latitude  which  are  nearly  equidistant 
from  each  other,  passing  through  Fargo,  Grand  Forks,  Emerson,  and  Glad- 
stone, respectively  75,  150,  224,  and  308  miles  north  of  Lake  Traverse. 
Though  the  fourth  of  these  intervals  is  somewhat  greater  than  the  others, 
it  may  still  be  considered  equivalent  to  them  in  the  observed  elevations  and 
northward  ascent  of  the  lake  shores,  because,  as  will  appeal-  further  on,  the 

474 


NOETHWARD  ASCENT  OP  THE  BEACHES.  475 

northward  rise  of  the  land  and  subsidence  of  the  lake  had  their  maximum 
increase  from  south-southwest  to  north-northeast  or  nearly  in  that  direction. 
Therefore  the  more  western  course  of  these  beaches  in  the  northern  part  of 
the  area  examined  compensates  approximately  for  the  additional  distance 
between  the  third  and  fourth  of  these  groups  of  observations. 

The  letters  a  h  c  d  represent  successive  beaches  along  the  northern 
part  of  Lake  Agassiz,  which  are  merged  in  a  single  beach  toward  its  south 
end.  Several  of  the  beaches  thus  noted  in  a  preliminary  report^  are  found 
to  become  double  in  some  parts  of  their  northward  extent,  and  a  corre- 
spondence in  notation  is  here  preserved  by  designating  subordinate  stages 
by  double  letters,  as  cm,  hh.  There  are  also  added  the  two  stages  of  the 
Tintah  beaches  which  were  discovered  after  the  publication  of  that  report. 

The  lake  shore  belonging  to  the  highest  or  Herman  stage  a  has  now  a 
northward  ascent  of  about  35  feet  in  the  first  75  miles  north  from  Lake 
Traverse,  about  60  feet  in  the  second  75  miles,  and  about  80  feet  in  the 
third  distance  of  74  miles  to  the  international  boundary.  Its  whole  ascent 
thus  in  224  miles  is  175  feet  by  a  slope  which  increases  from  slightly  less 
than  a  half  of  a  foot  per  mile  in  its  southern  third  to  slightly  more  than  1 
foot  per  mile  in  its  northern  third.  Througli  six  lower  stages  represented 
by  separate  beaches  northward,  which  seem  to  be  imited  in  the  single 
Herman  beach  along  the  southern  third  of  the  lake,  the  northward  ascent 
is  gradually  diminished  to  approximately  30,  40,  60,  and  70  feet  in  the  four 
poi-tious  of  the  observed  course  of  these  shore-lines,  amounting  thus  to  200 
feet  in  about  300  miles.  On  the  international  boundary  the  lowest  Herman 
stage,  dd,  is  about  55  feet  below  the  Herman  stage  a,  while  the  probable 
erosion  of  the  outlet  and  consequent  lowering  of  the  south  end  of  the  lake 
between  these  stages  appears  not  to  have  exceeded  10  feet. 

Between  the  series  of  Herman  beaches  and  the  series  of  Norcross 
beaches  the  River  Warren  eroded  its  chamiel  about  15  feet;  and  the  upper 
Norcross  shore  ascends  northward  in  these  successive  distances  about  25, 
35,  55,  and  70  feet,  amounting  to  185  feet  in  the  entire  distance  of  308 
miles.  In  the  most  southern  quarter  its  ascent  is  a  third  of  a  foot  per 
mile,  and  this  gradually  increases  to  nearly  1  foot  per  mile  in  the  most 

1  U.  S.  Geol.  Survey,  Bulletin  No.  39,  p.  20. 


476 


THE  GLACIAL  LAKE  AGASSIZ. 

Stages  of  the  glacial  Lalce  Agassiz^  western  shore. 


Beaches. 


Month  of 
Lake  Agas- 
siz  outtiow- 

ing  by  tlie 
River  War- 
ren, at  the 

north  end 
of  Lake 

Traverse. 


On  tbelutitiule 
of  Fargo  and 

Wbeathmd.  N. 

Dak.,  75  miles 

nortii  of  Lake 

Traverse. 


Ph 


0  > 


On  the  latitude 
of  Grand  Forks 

and  Larimore, 
N.  Dak.,  150 

miles  north  of 
Lake  Traverse. 


Ph 


On  the  inter- 
national boand- 
ary,  224  miles 
north  of  Lake 
Traverse, 


On  the  latitude 
of  Gladstone, 
Arden,  and 
Neepawa,  Man- 
itoba, 308  miles 
north  of  Lake 
Traverse. 


o  m 


2H 


Herman  beaches. 


Norcross  beaches  . 
Xintah  beaches  . . . 


5"- 


Campbell  beaches <^aa. 

b.. 

ra- 
McCanleyvllle  beaohea.<  aa . 

[b.. 


Blancharu  beaches <  &  . 

Hillsboro  beach 


Emerado  beaches  . 


lb. 


Ojata  beaches- 


Gladstone  beach . 

Bnrnside  beach. . 
Ossowa  beach  . . . 
Stonewall  beach. 


Niverville  beaches. 


1,055 

1.055 

1,050 

1,050 

1,045 

1,045 

1,045 

1,030 

1,025 

1,015 

1,000 

990 

985 

930 

970 

965 

960 

1(945) 

(935) 

(925) 

(915) 

(882) 

(880) 

(870) 

(860) 

(840) 

(822) 

(805) 

(795) 

(755) 

(750) 


1,090 

1,090 

1,085 

1,085 

1,080 

1,075 

1,075 

1,055 

1,050 

1,035 

1,017 

1,000 

995 

988 

977 

971 

965 

9,50 

940 

928 

918 


5 

(5) 
(5) 
(3) 
(3) 


1,150 

1,145 

1,135 

1,132 

1,125 

1,117 

1,115 

1,090 

1,080 

1,065 

1,045 

1,015 

1,010 

1,000 

987 

981 

975 

960 

948 

935 

923 

890 

885 

875 

865 

845 

827 


95 

90 
85 
82 
80 
72 
70 
60 
55 
50 
45 
25 
25 
20 
17 
16 
15 
(15) 
(13) 
(10) 
(8) 
(8) 
(5) 
(5) 
(5) 
(5) 
(5) 


1,230 

1,  222 

1,212 

1,205 

1,190 

1,180 

1,175 

1,145 

1,130 

1,105 

1,080 

1,045 

1,035 

1,022 

1,007 

998 

990 

975 

,960 

947 

935 

902 

897 

887 

877 

857 

837 

817 

805 


175 

167 

162 

155 

145 

135 

130 

115 

105 

90 

80 

55 

50 

42 

37 

33 

30 

(30) 

(25) 

(22) 

(20) 

(20) 

(17) 

(17) 

(17) 

(17) 

(15) 

(12) 

(10) 


1,315 

1,295 

1,275 

1,255 

1,245 

1,215 

1,185 

1,150 

1,120 

1,080 

1,070 

1,055 

1,035 

1,023 

1,012 

995 

980 

965 

953 

920 

915 

905 

895 

875 

855 

835 

820 

775 

770 


265 

245 

230 

210 

200 

185 

160 

135 

120 

90 

85 

75 

65 

58 

52 

(50) 

(45) 

(40) 

(38) 

(38) 

(35) 

(35) 

(35) 

(35) 

(33) 

(30) 

(25) 

(20) 

(20) 


'Figures  in  parentheses  in  the  first  column  of  elevations  give  approximately  the  heights  which  the  stages  of  the  lake 
dnring  its  outflow  northeastward  would  have  h,id  at  Lake  Traverse  if  the  land  there  had  been  low  enough  to  permit  the 
lake  to  extend  south  to  its  former  outlet.  From  these  estimated  elevations  tlie  northward  ascents  of  these  stages,  also  in 
parentheses,  are  obtained,  so  as  to  be  directly  compared  with  tlie  northward  ascents  of  the  beaches  that  were  formed  while 
the  lake  outflowed  southward,  showing  the  cliangea  which  were  gradually  taking  place  in  the  levels  of  the  beaches  of 
Lake  Agaaaiz  during  the  whole  time  of  its  existence. 


TABLES  OF  THE  WESTERN  BEACHES. 


477 


Stages  of  the  glacial  Lake  Agassiz,  tvestern  shore. 

[Contiuued  by  observations  of  Mr,  J.  B.  Tyrrell  in  the  region  of  Riding  and  Duck  moiintaina  and  northward.' 


i 
1 

1 

On  Valley  River, 

Manitoba,  375  miles 

north  of  Lake 

Traverse. 

On  Shanty  Creek, 

Manitolja,'395  milea 

nortli  of  Lake 

Traverse. 

On  Pine,  Duck,  and 
Swan  rivers,  Man- 
itoba, 420  to  440 
miles  north  of 
Lake  Traverse. 

On  Kettle  Hill,  Man- 
itoba, about  460 
miles  north  of 
Lake  Traverse. 

On  Mo38y  portage, 
and  at  the  Grand  Rap- 
ids of  the  Saskatche- 
wan River,  both  in 
the  Province  of 
Saskatchewan,  about 
510  miles  north  of 
Lake  Traverse. 

i 

03 
(D 

■s 

1 

ca 

a  . 
g 

12; 

gEB 
P 

'    /a 

■3 
1 
1 

1 

id 

a  > 

a§ 
II 

i 

j 

a  . 

O   oj 

as 

(25 

Id 

i| 

1 

1 

a  . 

§3 
K 

i 

d 
1-1 

h 

1 

S6 

II 

ig 
g  o 

1' 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

1,280 
1,260 
1,220 

250 
235 
205 

65 
75 
70 

1,365 
1,319 
1,287 
1,235 
1,190 
1,180 

335 
294 
272 
235 
200 
195 

150 
134 
137" 
115 
110 
.  110 

1,440 

410 

225 

1,365 

350 

215 

1,290 

300 

210 

1,135 

150 

65 

1,084 
1,075 

114 

110 



49 

52 

n,  120 

150 

85 

n,201 

231 

166 

11,040 

95 

45 

1,151 
1,130 

n.ioo 

1,030 

206 
195 
175 
115 

166 
150 
135 
77 

1,070 

1,015 

995 

155 
133 
115 

117 
95 
100 

960 

80 

60 

955 
920 

95 
80 

60 
45 

' 

910 
875 
845 
800 
790 

88 
70 
50 
45 
40 

55 

40 

25 

*>5 

20 

1  Estimated  from  its  elevation  of  1,025  feet  on  Ochre  River. 
*  Estimated  from  its  elevations  on  Valley  and  Pine  rivers. 

31,175  on  Pine  River;  1,201  on  Duck  River;  1,160  at  Square  Plain,  Swan  River. 

■'Estimated  approximately  for  the  vicinity  of  the  two  preceding;  about  1,075  feet  at  Oak  Creek,  on  the  north  side  of 
Swan  River. 


478  THE  GLACIAL  LAKE  AGASSIZ. 

uortliern  quarter.  These  rates  of  ascent  are  slightly  reduced  in  the  second 
Norcross  stage,  where  the  total  ascent  is  160  feet.  While  the  outlet  was 
being  eroded  probably  5  feet  between  the  Norcros&  stages,  the  combined 
rise  of  the  land  and  decline  of  the  lake  level  were  about  10  feet  on  the 
international  boundary  and  25  feet  on  the  latitude  of  Gladstone.  The  lake 
shore  belonging  to  the  Tintah  stage  a  ascends  about  20,  30,  40,  and  45  feet 
in  the  successive  distances  from  south  to  north,  amounting  in  total  to  135 
feet;  in  the  same  distances  the  Campbell  a  shore  ascends  about  10,  15,  30, 
and  35  feet,  in  total  90  feet;  the  McCauleyville  a  shore  ascends  about  7,  10, 
20,  and  28  feet,  in  total  65  feet;  and  the  McCauleyville  h  shore  ascends  about 
5,  10,  15,  and  22  feet,  in  total  52  feet.  The  erosion  of  tlie  River  Warren 
from  the  Norcross  a  stage  to  the  McCauleyville  h  stage,  at  the  end  of  which 
the  southward  outflow  ceased,  was  about  70  feet;  but  the  vertical  distance 
between  the  shore-lines  of  these  stages  on  the  latitude  of  Gladstone  is 
about  200  feet,  the  difference  of  130  feet  being  attributable  to  the  north- 
ward rise  of  the  land  and  the  fall  of  the  lake  level  on  account  of  the 
dimuiished  attraction  of  the  ice-sheet.  The  rate  of  northward  ascent  is 
reduced  to  less  than  an  inch  per  mile  along  the  southern  part  of  the  lowest 
McCauleyville  shore,  and  to  3  or  4  inches  per  mile  along  its  northern  part, 
the  average  being  2  inches. 

From  the  time  of  this  lowest  beach,  formed  during  the  southward 
outflow  of  Lake  Agassiz,  to  the  time*  of  the  first  beach,  formed  during  its 
northeastward  outflow,  the  lake  fell  only  about  15  feet.  Thence  there  is 
now  a  descent,  on  the  latitude  of  Gladstone,  of  about  220  feet  to  the 
Niverville  beach,  below  which  Lake  Agassiz,  while  its  northern  barrier  of 
ice  remained,  fell  about  45  feet  more  before  it  was  reduced  to  Lake  Winni- 
peg. The  northward  ascent  of  these  shore-lines  of  northeastward  outlet 
decreases  only  slightly  in  the  distance  of  75  or  80  miles  examined  north  of 
the  international  boundary,  the  change  being  approximately  from  20  feet 
to  15  feet  or  less — that  is,  to  the  rate  of  about  2  inches  per  mile.  If  these 
stages  of  the  lake  had  reached  south  to  Lake  Traverse,  they  would  proba- 
bly show  a  decrease  from  about  50  to  25  feet,  or  to  20  feet,  in  their  total 
northward  ascent  above  the  level  of  the  present  time  along  the  distance  of 


NOETHWAED  ASCENT  OF  THE  BEACHES.  479 

more  than  300  miles  from  Lake  Traverse  to  tlie  south  ends  of  Lakes  Mani- 
toba and  Winnipeg.  The  whole  descent,  on  the  latitude  of  Gladstone, 
between  the  lowest  McCauleyville  beach,  where  Lake  Agassiz  ceased  to 
outflow  southward,  and  the  original  level  of  Lake  Winnipeg,  about  20  feet 
above  the  present  surface  of  that  lake,  is  about  280  feet,  of  which  probably 
25  or  30  feet  may  be  due  to  the  northward  rise  of  the  land  and  diminution 
of  gravitation  toward  the  ice-sheet,  while  about  250  feet  are  due  to  the 
gradual  lowering  of  Lake  Agassiz  by  its  successive  northeastern  outlets. 

The  depth  of  Lake  Agassiz  above  the  present  surface  of  the  south  end 
of  Lake  Winnipeg  was  about  600  feet  during  its  higher  Herman  stages,  500 
feet  at  the  upper  Norcross  stage,  440  feet  at  the  upper  Tintah  stage,  370  feet 
at  the  upper  Campbell  stage,  and  325  and  300  feet  in  the  upper  and  lower 
McCauleyville  stages,  being  thus  reduced  to  half  of  its  earHer  depth  before 
it  ceased  to  flow  to  the  south.  During  the  lower  stages  of  outflow  to  the 
northeast  the  depth  of  Lake  Agassiz  above  Lake  Winnipeg  decreased  to 
285  feet  at  the  upper  Blanchard  stage,  about  240  feet  at  the  time  of  the 
Hillsboro  beach,  210  feet  in  the  Emerado  stage,  and  successively  about  185, 
165,  145,  130,  110,  and  65  feet  in  the  Ojata,  Gladstone,  Burnside,  Ossowa, 
Stonewall,  and  Niverville  stages. 

The  greatest  expansion  of  Lake  Agassiz  was  perhaps  reached  before 
the  Herman  series  of  beaches  was  completed,  and  it  apparently  was  main- 
tained during  the  greater  part  of  the  time  of  outflow  by  the  River  Warren; 
but  through  the  successive  stages  of  outflow  northeastward  the  lake  was 
diminished  in  area  by  nearly  proportionate  gradations  as  its  depth  decreased. 
When  it  began  to  flow  in  this  direction  it  probably  still  occupied  about 
half  of  its  area  that  was  attained  during  the  formation  of  the  Herman  and 
Norcross  beaches;  but,  in  compensation  for  loss  on  its  western  and  southern 
borders,  it  may  have  received  meanwhile  as  great  addition  by  growth 
toward  the  north  and  northeast,  thus  retaining,  until  it  ceased  to  outflow  at 
Lake  Traverse,  nearly  its  maximum  extent. 

Beyond  the  limits  of  my  leveling,  portions  of  nearly  all  the  shore-Hnes 
of  Lake  Agassiz  below  those  of  the  Herman  series  have  been  observed  by 
Mr.  J.  B.  Tyrrell,  of  the  Canadian  Geological  Survey,  at  localities  in  north- 
western Manitoba  and  eastern  Saskatchewan.     From  a  careful  comparison 


480  THE  GLACIAL  LAKE  AGASSIZ. 

of  the  elevation  of  the  beaclies  noted  by  Mr.  Tyn'ell  with  those  deteraiined 
by  my  survey,  I  am  enabled  to  correlate  very  satisfactorily  the  two  sets  of 
shore-lines.  The  northern  continuations  of  the  successive  lake  levels  from 
the  upper  Norcross  stage  to  the  Niverville  stages,  inclusive,  are  thus  identi- 
fied upon  a  region  lying  50  to  200  miles  beyond  the  area  examined  by  me. 
This  correlation  has  been  tabularly  presented  on  page  477,  in  juxtaposition 
with  the  table  showing  how  the  shore-lines  ascend  along  their  extent  from 
Lake  Traverse  to  Gladstone. 

In  the  southern  area  of  my  exploration  nearly  equal  distances  divide 
the  several  sections  across  the  shore-lines  which  are  compared  together; 
but  upon  the  country  described  by  Mr.  Tyrrell  the  spaces  dividing  succes- 
sive sections  are  of  various  lengths.  Between  the  latitude  of  Gladstone  and 
the  Valley  River  is  a  distance  of  67  miles.  Thence  to  Shanty  Creek,  the 
next  locality  of  numerous  observations,  there  is  an  interval  of  only  20 
miles.  Notations  of  the  heights  of  nine  beaches  near  the  Pine,  Duck,  and 
Swan  rivers  are  upon  an  area  25  to  45  miles  farther  north.  In  this  group 
the  observations  in  the  valley  of  the  Swan  River  are  20  to  30  miles  west 
of  the  others,  and  therefore  have,  on  account  of  the  north-northeastward 
du-ection  of  the  ascent  of  the  former  lake  levels,  a  nearer  equivalence  with 
the  elevations  of  beaches  on  the  Pine  River  than  on  the  Duck  River.  The 
fourth  series  of  beaches  recorded  is  on  Kettle  Hill,  close  south  of  Swan 
Lake,  at  a  distance  of  some  20  or  25  miles  north  from  the  Duck  River 
and  the  northern  end  of  Duck  Mountain,  and  about  150  miles  north  from 
the  latitude  of  Gladstone.  Finally,  the  fifth  series  was  noted  on  Mossy 
portage  and  at  the  Grand  Rapids  of  the  Saskatchewan,  about  50  miles  north 
of  the  last. 

As  already  stated  in  Chapters  V  and  VIII,  the  beaches  east  and  north 
of  Riding  and  Duck  mountains  are  found  to  have  a  more  rapid  northward 
ascent  than  along  their  southern  portion  traced  by  my  leveling.  It  is  also 
very  noteworthy  that  this  large  amount  of  differential  uplifting  was  chiefly 
done  after  the  time  of  formation  of  the  Campbell  beaches,  whereas  nearly 
all  the  uplifting  of  the  area  from  the  southern  mouth  of  Lake  Agassiz  to 
Gladstone  had  taken  place  earlier.  During  the  first  third  or  half  of  the 
period  of  the  entu-e  duration  of  Lake  Agassiz  the  southern  and  central  part 


PEOGEESSIVE  UPLIFT  FROM  HOUTH  TO  NORTH.  481 

of  the  lake  basin,  reaching  north  to  Gladstone,  had  been  raised  nearly  to 
its  present  height.  Then  followed  a  time,  during  the  second  third  of  the 
lake's  existence,  in  which  the  district  that  includes  Riding  and  Duck  moun- 
tains and  extends  north  to  the  mouth  of  the  Saskatchewan  was  being  rapidly 
uplifted.  But  this  later  northward  and  northeastward  advance  of  the  wave 
of  upheaval  had  passed  beyond  the  Saskatchewan  before  Lake  Agassiz 
was  reduced  to  Lake  Winnipeg,  as  is  shown  by  the  nearly  level  Niverville 
beaches,  the  latest  formed  while  the  ice  barrier  remained.  The  rise  of  the 
land  approximately  to  its  present  height  is  thus  known  to  have  followed 
close  upon  the  glacial  recession  by  which  the  land  was  relieved  of  the  ice 
weight. 

The  remnants  of  the  ice-sheet  adjoining  Hudson  Bay  were  not  melted 
away  until  the  Recent  or  post-Glacial  epoch  had  begun  in  the  northern 
United  States,  their  departure  being  possibly  even  nearer  to  the  present 
day  than  to  the  time  of  withdrawal  of  the  ice  barrier  of  Lake  Agassiz. 
Moving  onward  pari  passu  with  the  departure  of  the  ice,  the  uplifting  wave 
of  the  earth's  crust  has  raised  the  basin  of  Hudson  Bay  300  to  500  feet 
since  the  sea  was  admitted  to  it,  and  the  upheaval  there  is  not  yet  com- 
pleted. Though  doubtless  slower  than  at  first,  it  is  still  in  progress, 
according  to  Dr.  Bell's  observations,  at  a  probable  rate  of  5  to  7  feet  per 
century. 

Three  stages  of  the  elevation  of  this  region  from  its  Champlain  subsid- 
ence are  thus  indicated  by  the  beaches  of  Lake  Agassiz  and  the  fossiliferous 
marine  beds  overlying  the  till  about  Hudson  Bay,  the  first  extending  from 
Lake  Traverse  to  Gladstone  and  the  south  end  of  Riding  Mountain,  the 
second  reaching  thence  probably  to  the  northern  and  northeastern  limits 
of  the  area  that  was  occupied  by  Lake  Agassiz,  and  the  third  affecting 
the  basin  of  James  and  Hudson  bays.  On  the  conunon  borders  of  these 
contiguous  areas  the  uplifts  were  of  course  interblended ;  but  it  seems  to 
be  clearly  shown  by  the  Campbell  and  Niverville  beaches  that  there  was 
essential  rest  from  the  uplifting  movement,  with  a  permanence  of  height 
nearly  as  now,  upon  the  southern  part  of  the  basin  of  Lake  Agassiz  while 
its  northern  part  was  rising,  and  afterward  upon  the  whole  of  this  basin 
while  the  country  surrounding  Hudson  Bay  has  been  elevated.  A  wave  of 
MON  XXV 31 


482  THE  GLACIAL  LAKE  AGASSIZ. 

permanent  uplift  lias  advanced  from  near  the  southern  border  of  the  glaci- 
ated area  to  its  central  jjortion,  where  the  ice-sheet  was  thickest  and  where 
it  lingered  in  remnants  probably  long  after  its  principal  mass  was  melted.^ 

According  to  my  correlation,  the  highest  beach  observed  by  Mr.  Tyr- 
rell east  of  Riding  and  Duck  mountains  belongs  to  the  upper  Norcross 
stage  of  Lake  Agassiz,  which  now  has  an  ascent  of  410  feet  from  its  mouth, 
near  Lake  Traverse,  to  Pine  River,  in  a  distance  of  about  420  miles.  The 
rate  of  ascent  of  this  beach  from  the  latitude  of  Gladstone  to  Valley  River 
is  about  1  foot  per  mile,  but  thence  for  nearly  50  miles  northward  to  Pine 
River  it  somewhat  exceeds  3  feet.  The  same  I'ates  of  ascent  continue,  with 
only  slight  changes  in  the  Tintah  and  Campbell  beaches,  for  the  distances 
from  the  latitude  of  Gladstone  to  the  Valley  and  Pine  rivers.  This  portion 
of  the  western  shore  of  Lake  Agassiz  had  risen  almost  uniformly  through- 
out its  extent  while  these  beaches  were  being  formed.  It  had  been  lifted 
as  a  whole  to  the  same  amount  as  its  southern  part  near  Gladstone,  but  it 
experienced  scarcely  any  diiferential  elevation  or  tilting  until  after  the 
formation  of  the  Campbell  beaches. 

The  rate  of  northward  ascent  of  the  upper  McCauleyville  beach  is  9 
inches  per  mile  between  Gladstone  and  the  Valley  River,  and  thence 
northward  for  55  miles  to  the  Duck  River  it  ascends  a  little  more  than 
2  feet  per  mile.  In  the  case  of  the  upper  Blanchard  beach,  the  lowest 
noted  near  the  Valley  River,  these  rates  of  ascent  are  respectively  8  inches 
and  2  feet. 

After  Lake  Agassiz  began  to  outflow  northeastward,  the  differential 
northward  uplifting  of  this  district  of  the  Riding  and  Duck  mountains  went 
on  rapidly,  amounting  probably  to  70  feet  within  the  distance  of  50  miles 
next  northward  from  the  Valley  River  during  the  time  between  the  upper 
Blanchard  beach  and  the  lower  Emerado  beach.  The  latter  has  an  ascent 
of  only  60  feet  in  about  110  miles  northward  from  Gladstone  to  the  Pine 
River,  while  in  the  next  40  miles  north  to  Kettle  Hill  it  rises,  like  the 
preceding  Hillsboro  beach,  1  foot  per  mile. 

Below  these  shore-lines  the  later  lake  levels  have  been  changed  com- 
paratively little  from  their  original  horizontality.     In  the  distance  of  150 

'Journal  of  Geology,  Vol.  II,  jip.  383-395,  May-Juue,  1894. 


THE  UPLIFT  GRADUAL,  WITHOUT  FAULTING.  483 

miles  northward  fi'om  tlie  latitude  of  Gladstone  to  Kettle  Hill  the  lower 
Ojata  beach  and  the  Gladstone  beach  ascend,  respectively,  60  and  45  feet; 
and  in  200  miles  from  Gladstone  to  the  Mossy  portage  and  the  mouth 
of  the  Saskatchewan  the  successive  ascents  of  the  Burnside,  Ossowa,  and 
Stonewall  beaches  are  55,  40,  and  25  feet,  or  only  about  3  inches  to  1^ 
inches  per  mile. 

The  very  regular  northward  rise  of  the  beaches  of  this  lake  throughout 
all  their  explored  extent,  nowhere  having  any  abrupt  changes  of  level, 
indicates  clearly  that  this  region  has  not  experienced  violent  orogenic  dis- 
turbance nor  faulting  since  the  departure  of  the  ice-sheet.  Its  changes  of 
level,  which  have  been  of  large  amount,  as  shown  by  the  tilted  planes  of  the 
former  lake  surfaces,  took  place  gradually  and  continued  through  the  entire 
duration  of  the  lake.  They  went  forward  most  rapidly  upon  the  areas 
which  had  been  latest  bared  from  the  retreating  ice-sheet,  and  they  were 
essentially  finished,  bringing  the  basin  to  the  same  height  and  attitude 
as  now  before  the  ice  barrier  was  removed  from  the  course  of  the  Nelson 
River.  The  continuity  of  the  beaches  and  the  slow  and  gradual  changes 
in  their  gradients  prove  that  no  faults  or  dislocations  attended  the  uplifting, 
tilting,  and  bending  of  the  subjacent  rock  formations. 

EASTWARD  ASCENT  OF  THE  FORMER  LAKE  liEVELS, 

Exploration  of  the  beaches  formed  on  the  east  side  of  Lake  Agassiz 
has  been  mostly  limited  to  Minnesota,  because  the  eastern  part  of  this  lake 
area  in  Manitoba  is  covered  by  forest  and  is  almost  wholly  without  settle- 
ments or  roads,  so  that  for  the  present  a  survey  of  the  shore-lines  there  is 
impracticable.  For  the  same  reasons  the  upper  shores  in  Minnesota  have 
not  been  exactly  traced  east  of  Maple  Lake,  which  lies  20  miles  east- 
southeast  of  Crookston.  Within  the  prairie  area  across  Avhicli  the  highest 
eastern  shore  has  been  surveyed  and  its  elevation  determined  by  leveling 
its  northward  ascent  is  about  115  feet  in  140  miles,  from  1,055  feet  above 
the  sea  at  Lake  Traverse  to  1,170  feet  at  the  north  side  of  Maple  Lake.  As 
on  the  western  shore  of  Lake  Agassiz,  the  rate  of  ascent  gradually  increases 
from  south  to  north,  ranging  from  6  inches  to  1  foot  per  mile  in  its  southern 


484  THE  GLACIAL  LAKE  AGASSIZ. 

portion  for  about  75  miles,  and  from  1  foot  to  16  inches  per  mile  farther 
north.  Before  the  lake  in  Minnesota  had  fallen  below  its  highest  eastern 
beach  iu  the  south  half  of  its  explored  extent  the  rise  of  the  land  and 
diminution  of  attraction  of  the  waning  ice-sheet  had  caused  a  slightly  lower 
parallel  beach,  three-fourths  of  a  mile  to  IJ  miles  distant,  to  be  formed 
through  the  northern  third  of  Clay  County;  and  this  secondary  beach, 
sometimes  double  or  triple,  is  observable  at  several  places  along  the  next 
30  miles  northward.  At  the  northwest  side  of  Maple  Lake  definite  beach 
ridges  belonging  to  the  Herman  stages  of  Lake  Agassiz  lie  successively 
about  8,  15,  30,  and  45  feet  below  its  highest  beach.  Yet  all  these  shore- 
lines were  formed  while  the  relative  heights  of  the  land  and  the  lake 
continued  stationary  or  with  only  slight  change,  not  sufficient  for  the 
formation  of  any  secondary  beach  ridge,  along  a  distance  of  some  75  miles 
northward  from  Lake  Traverse  and  Herman. 

The  Norcross  beaches  in  Minnesota  have  been  explored  and  their 
height  measured  through  the  same  extent  of  140  miles,  in  which  the  upper 
Norcross  beach  ascends  northward  about  65  feet  by  a  slope  that  increases 
slightly  from  south  to  north,  averaging  nearly  6  inches  per  mile.  In  like 
manner  the  northward  ascents  of  the  Tintah,  Campbell,  and  McCauleyville 
beaches  in  Minnesota,  and  of  the  lower  beaches  formed  on  this  east  side  of 
the  lake  during  its  outflow  to  the  northeast,  show  a  gradual  decrease  nearly 
as  on  the  west  in  North  Dakota  and  Manitoba. 

But  comparison  of  the  western  and  eastern  shores  reveals  another  very 
interesting  feature  of  the  levels  of  this  glacial  lake,  namely,  an  ascent  from 
west  to  east  similar  to  that  from  south  to  north,  but  of  less  amount  and 
diminishing  in  a  similar  ratio  between  the  successive  stages  of  the  lake. 
On  the  latitude  of  Larimore  and  Grand  Forks  the  ascent  of  the  highest 
Herman  stage  of  Lake  Agassiz  above  a  line  now  level  is  approximately 
33  feet  in  about  70  miles  from  west  to  east,  the  rate  per  mile  being  very 
nearly  half  as  much  as  from  south  to  north;  and  in  the  later  Herman 
stages  it  is  diminished  to  about  30,  25,  and  20  feet.  On  the  Norcross 
shore-lines  this  ascent  toward  the  east  is  approximately  10  feet  iu  about  60 
miles,  and  it  is  reduced  in  the  McCauleyville  stages  to  only  3  or  4  feet  in 
about  50  miles;  yet  it  continues  through  all  these  stages  approximately  half 


MAXIMUM  ASCENT  NOETH-NOETHEASTWAED.  485 

as  much  per  mile  as  the  ascent  toward  the  north.  The  rate  of  ascent  east- 
ward also  increases,  like  that  northward,  in  proceeding  from  south  to  north. 
At  the  latitude  of  Wahpeton  and  Breckenridge,  35  miles  north  from  the 
mouth  of  Lake  Agassiz,  the  ascent  of  its  highest  stage  is  10  feet  from  west 
to  east  in  45  miles;  at  the  latitude  of  Fargo  and  Moorhead,  75  miles  north 
from  the  outlet,  it  is  15  feet  in  50  miles;  and  at  the  latitude  of  Grand 
Forks,  150  miles  north  from  the  outlet,  it  is  33  feet  in  70  miles. 

BATE  OF  ASCENT  GREATEST  TOWARD  THE  NORTH-NORTHEAST. 

These  observations  that  the  corresponding  beaches  are  higher  on  the 
east  than  on  the  west  side  of  the  lake,  taken  in  connection  with  the  doubly 
more  rapid  northward  ascent  of  the  west  and  east  shores,  indicate  that  the 
changes  in  the  relations  of  the  land  and  surfaces  of  level  during  the  exist- 
ence of  Lake  Agassiz  and  through  subsequent  time  have  given  to  the 
former  levels  of  this  glacial  lake  a  maximum  ascent  from  south-southwest 
to  north-northeast,  its  rate  in  this  direction  being  somewhat  greater  than 
that  noted  in  following  the  shores  in  their  nearly  due-north  course.  The 
maximum  rates  of  northward  ascent  of  about  1  foot  per  mile  observed  in 
North  Dakota  and  southern  Manitoba,  and  of  1  foot  to  1 6  inches  per  mile 
in  Minnesota,  therefore  belong  to  a  lake  level  which  in  its  northern  por- 
tion, within  the  limits  of  my  exploration,  differs  from  the  present  level  by 
an  ascent  of  approximately  IJ  feet  per  mile  toward  the  north-northeast. 
Similar  north-northeastward  ascent  continues  through  the  successive  lower 
stages  of  the  lake,  in  which  its  amount  in  southern  Manitoba,  between  the 
international  boundary  and  Gladstone,  is  reduced  to  about  4  inches  per 
mile  at  the  lowest  stage  of  southward  outflow;  and  it  is  scarcely  1  inch 
per  mile  in  the  Niverville  beaches  along  their  whole  observed  extent  of 
about  260  miles  from  Morris,  Manitoba,  north  to  the  mouth  of  the  Sas- 
katchewan. No  more  than  20  feet  of  differential  northward  uplift  has 
taken  place  within  this  distance  since  the  course  of  the  Nelson  River  was 
uncovered  by  the  I'eceding  ice-sheet. 

Preliminary  descrijjtions  and  discussions  of  the  uplifting  of  this  basin 
which  have  been  given  in  the  chapter  on  the  history  of  Lake  Agassiz 


486  THE  GLACIAL  LAKE  AGASSIZ. 

showed  that  the  movement  of  elevation  of  the  country  at  Late  Traverse 
after  the  ice  above  was  melted  probably  did  not  exceed  90  feet;  that  thence 
northward  the  rise  of  the  land  and  sinking  of  the  geoid  level,  as  affected  by 
ice  attraction,  increased  to  a  combined  value  of  about  350  feet  at  Gladstone 
and  nearly  500  feet  in  the  district  of  the  northern  part  of  Duck  Mountain, 
where,  as  in  Noi'th  Dakota  and  Minnesota,  the  maximum  rate  of  ascent  of 
the  beach  planes  is  toward  the  north-northeast;  and  that  probably  thence 
north  to  the  Saskatchewan  and  the  Churchill,  northeast  to  Hudson  Bay, 
and  east  to  James  Bay,  the  Ottawa  basin,  and  Montreal,  the  amount  of 
uplift,  since  the  departure  of  the  ice,  of  a  very  large  central  part  of  the 
area  which  it  had  covered  was  somewhat  uniformly  500  to  600  feet.  It 
has  been  also  shown  from  Mr.  Tyrrell's  observations  in  the  district  of  Riding 
and  Duck  mountains  that  after  the  southern  half  of  the  lake  area  had  been 
raised  almost  to  its  present  height,  and  while  that  country  north  to  Glad- 
stone lay  nearly  undisturbed,  a  great  uplift  of  later  date  took  place  in 
the  next  100  miles  to  the  north;  and  that,  after  both  these  movements,  the 
region  of  Hudson  and  James  bays  was  still  later  raised,  probably  from  its 
maximum  depression  to  its  present  height.  Throughout  the  area  of  my 
survey  of  the  Lake  Agassiz  shore-lines,  and  northward  along  the  Riding 
and  Duck  mountains,  the  epeirogenic  movement  was  a  tilting  with  ascent 
to  the  north-northeast,  toward  the  region  Avhere  the  ice-sheet  had  its  greatest 
thickness;  but  the  more  northern  and  northeastern  part  of  this  lake  bed, 
with  a  great  adjoining  central  portion  of  the  vast  expanse  which  had  been 
ice-enveloped,  were  elevated  to  an  approximately  uniform  amount.  The 
elevation  progressed  from  south  to  north  and  northeast  like  a  wave,  per- 
manently uplifting  successive  areas,  excepting  so  far  as  the  borders  of  each 
necessarily  shared  in  the  movements  of  the  contiguous  tracts  earlier  or  later 
uplifted. 

CHANGES  OF  LEVELS  NEARLY  COMPLETED  DURING  THE  EXISTENCE 

OF  LAKE  AGASSIZ. 

Nearly  the  entire  amount  of  the  changes  in  the  levels  of  the  beaches 
of  Lake  Agassiz  was  evidently  contemporaneous  with  the  existence  of  this 
lake,  taking  place  gradually,  but  apparently  progi'essing  comparatively  fast 


EARLY  COMPLETION"  OF  THE  UPLIFT.  487 

between  the  stages  marked  by  the  formation  of  definite  beaches,  which 
doubtless  belong  to  times  when  these  changes  advanced  very  slowly  or 
were  interrupted  by  intervals  of  repose.  Great  as  were  the  combined 
epeirogenic  uplift  and  modification  of  the  geoid  surface  of  level,  producing 
a  differential  rise  of  the  highest  western  shore  of  the  lake  in  Manitoba  to 
the  extent  of  175  feet  at  the  international  boundary,  266  feet  at  the  latitude 
of  Gladstone,  and  about  400  feet  at  the  latitude  of  51°  52'  north  on  the 
east  side  of  Duck  Mountain,  200  miles  north  of  the  international  boundary, 
in  the  relation  of  the  land  to  the  water  level,  as  compared  with  the  vicinity 
of  Lake  Traverse,  they  were  yet  almost  or  perhaps  quite  completed  before 
the  ice-sheet  was  so  far  withdrawn  that  it  was  no  longer  a  barrier  to  prevent 
free  drainage  from  the  basin  of  the  Red  River  and  Lake  Winnipeg. 

During  the  subsequent  postglacial  period,  to  the  present  time,  only 
very  slight  changes  have  taken  place  in  the  relative  elevations  of  the  part 
of  this  area,  where  the  heights  of  the  beaches  of  Lake  Agassiz  have  been 
determined  in  Minnesota,  North  Dakota,  and  Manitoba;  and  these  small 
changes  of  level,  shown  by  the  Niverville  beaches,  have  been  merely  a 
continuation  of  the  movements  which  accompanied  the  recession  of  the 
ice-sheet  and  are  recorded  by  the  successive  shore-lines  of  this  lake. 

CAUSES  OF  THE   CHAIfGES  OF   LEVELS. 

In  attempting  to  discern  the  causes  of  the  changes  of  levels  shown 
by  the  shore-lines  of  Lake  Agassiz,  three  diverse  agencies,  which  certainly 
must  have  been  factors  working  together  to  produce  the  observed  results, 
are  to  be  studied  with  respect  to  the  proportion  contributed  by  each.  They 
are  considered  in  the  following  order:  (1)  Gravitation  of  the  water  of  Lake 
Agassiz  toward  the  ice-sheet;  (2)  changes  in  the  temperature  of  the  earth's 
crust  due  to  the  ice-sheet,  or,  in  other  words,  to  the  cold  of  the  Glacial 
period  and  the  return  of  the  warmer  climate  now  enjoyed;  (3)  epeirogenic 
movements,  or  downward  and  upward  bending,  often  more  or  less  accom- 
panied with  the  formation  of  faults,  affecting'  large  areas  of  the  earth's 
surface,  which  may  be  due  («)  to  the  imposed  weight  of  the  ice-sheet 
and  to  its  removal,  or  (h)  to  conditions  and  stresses  of  the  earth's  crust  and 
interior  originating  otherwise,  as  by  secular  cooling  and  contraction. 


488  THE  GLACIAL  LAKE  AGASSIZ. 

The  order  in  which  we  shall  thus  examine  these  several  parts  of  the 
complex  causation  of  the  changes  of  levels  is  not,  however,  the  order  of 
their  importance  or  several  shares  in  the  work.  The  third  agency,  mani- 
fested in  obedience  to  the  pressure  of  the  ice  and  in  resilience  when  relieved 
from  it,  is  found  to  have  been  the  prinoipal  factor,  producing  far  the  greater 
part  of  the  changes  of  levels.  Its  manifestation  within  the  area  of  Lake 
Agassiz  during  the  Glacial  and  Recent  periods  on  account  of  the  other 
conditions  and  stresses  mentioned  appears  to  be  only  a  small  element  in 
the  problem;  though,  when  thus  originating,  it  is  seen  to  have  had  great 
importance  in  causing  such  changes  in  other  parts  of  the  world,  and  even  in 
parts  of  North  America,  contemporaneously  with  the  uplifting  of  the  basin 
of  this  lake.  The  first  agency  noted  is  found  to  be  a  considerable  factor, 
working'  in  the  same  directions  as  the  epeirogenic  effects  of  the  transient 
ice  weight,  and  contributing  perhaps  a  fifth  or  a  fourth  as  much  toward  the 
changed  relations  of  the  water  level  and  the  land  area.  But  the  second 
agency,  upon  investigation,  proves  to  have  been  slight  in  its  effect,  and 
within  the  basin  of  Lake  Agassiz,  so  far  as  it  availed,  it  was  opposed  to  the 
other  two. 

GRAVITATION   TOWARD    THE    ICE-SHEET. 

Consideration  of  the  character  of  the  changes  in  the  levels  of  the 
beaches,  resulting  in  a  greater  ascent  upon  the  northern  part  of  the  area 
examined  than  farther  south,  and  gradually  approximating,  tlu'ough  the 
successive  stages  of  the  lake,  to  parallelism  with  the  present  geoid  surface 
of  level,  led  me  in  my  earlier  studies  to  attribute  these  changes  almost 
wholly  to  gravitation  of  the  water  of  the  lake  toward  the  ice-sheet.  The 
cause  of  the  present  relations  of  the  old  shore-lines  seemed  to  be  discov- 
ered in  the  explanation  that  at  first  this  attraction  had  a  large  effect  upon 
the  lake  level  because  of  the  nearness  of  a  great  depth  of  ice  on  the  east 
in  northern  Minnesota  and  on  the  north  in  British  America,  but  that  after- 
ward it  was  gradually  diminished  to  a  comparatively  small  influence  when 
the  southern  portion  of  the  ice-sheet  had  been  melted  and  the  attracting 
force  proceeded  from  the  region  far  north  between  Lake  Winnipeg  and 
Hudson  Bay.*     Under  this  view  the  earth's  crust  was  believed  to  be  so 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Eleventh  Annual  Report,  p.  152 ;  U.  S.  Geol.  Survey, 
Bulletin  No.  39,  p.  18. 


GRAVITATION  TOWAED  THE  lOE-SHEET.  489 

rigid  that  it  was  not  depressed  hj  the  vast  weight  of  the  ice  nor  raised 
when  relieved  of  that  weight,  and  the  changes  were  believed  to  consist 
chiefly  in  the  differential  subsidence  of  the  lake  level,  not  in  the  differ- 
ential elevation  of  the  land  basin.^  The  general  nniformity  of  these 
changes  in  their  direction  and  extent,  and  their  probable  completion  during 
the  departure  of  the  ice-sheet,  seemed  to  accord  with  this  hypothesis. 
The  exact  comparison  of  the  shore-lines  siirveyed  by  me,  with  leveling,  on 
both  the  east  and  west  sides  of  the  lake,  extending  for  its  upper  stages  140 
miles  from  south  to  north  in  Minnesota  and  more  than  300  miles  from 
south  to  north  in  North  Dakota  and  southern  Manitoba,  shows  no  con- 
siderable irregularity  in  the  rates  of  northward  and  eastward  ascent — that, 
is,  of  north-northeastward  ascent — of  the  former  lake  levels,  which  thus 
seem  to  be  attributable  to  gravitation  toward  the  waning  ice-sheet,  rather 
tlian  to  a  progressive  elevation  of  the  land,  for  that  would  be  expected  to 
present  noteworthy  irregularities  upon  so  large  an  area.  It  is  probable, 
however,  that  close  scrutiny  of  the  shore-lines  will  disclose  small  diverg- 
ences, within  limits  of  a  few  feet,  from  the  uniformity  of  slopes  which 
they  should  have  for  agreement  with  this  explanation;  and  it  is  to  be 
noticed  that  the  highest  shores  in  the  vicinity  of  Treherne,  Brandon,  and 
Neepawa,  Manitoba,  have  more  nearly  a  northward  than  north-north- 
eastward ascent;  also  that  a  slightly  disproportionate  increase  in  the  ascent 
of  the  highest  Minnesota  shore-line  in  the  next  10  or  15  miles  north  of  the 
Buffalo  River  was  ascribed  to  the  proximity  of  a  portion  of  the  ice-sheet 
on  the  east,  where  it  was  forming  the  Fergus  Falls  and  Leaf  Hills  moraines. 
Though  it  now  appears  true  that  the  greater  part  of  these  changes  of  level 
are  due  to  the  differential  rise  of  the  land,  the  gravitation  of  the  lake 
toward  the  ice-sheet  certainly  operated  in  conjunction  with  that  cause, 
contributing  to  the  full  extent  of  its  competency  in  producing  the  results 
observed. 

Mr.  R.  S.  Woodward,   of  the  United  States    Geological  Survey,  has 
worked  out  the  mathematical  problem  of  determining  the  effect  of  any 

•  Similar  oscillations  in  tlie  relative  heights  of  sea  and  land,  associated  with  glaciation,  have  been 
thus  ascribed  to  ice  attraction  by  Atlhemar,  in  Revolutions  de  la  Mer,  1840;  by  CroU,  in  Climate  and 
Time,  1875;  and  by  Peuck,  in  Schvi^aukungen  des  Meeresspiegels,  Jahrbuch  der  GeograiJhischen 
Gesellschaft  zu  MUnchen,  bd.  VII,  1882. 


490  THE  GLACIAL  LAKE  AGASSIZ. 

added  mass,  as  an  ice-sheet,  upon  the  eartli's  surface,  to  distiu'b  the  levels 
of  the  sea  and  of  lakes.^  Assuming'  an  ice-sheet  with  a  radial  extent  of  38°, 
or  about  2, GOO  miles,  and  a  central  depth  of  10,000  feet,  from  which  the 
depth  decreases  at  first  slowly  and  then  more  rapidly  to  its  border,  he  finds 
that  the  average  slope  witliiu  1  degree  of  the  border  of  the  ice  would  be 
about  5  inches  per  mile,  or  less  than  one-third  of  the  north-northeastward 
ascent  of  the  highest  shore-lines  of  Lake  Agassiz  in  the  north  part  of  the 
area  where  they  have  been  traced  with  leveling.  If  we  compare  the  prem- 
ises in  this  problem  with  the  probable  conditions  affecting  this  glacial  lake, 
it  seems  sure  that  the  North  American  ice-sheet  in  its  maximum  extent 
covered  not  more  than  about  one-fourth  so  great  an  area,  its  extent  being 
equivalent  to  a  spherical  circle  with  a  radius  of  1,200  or  1,300  miles;  but, 
on  the  other  hand,  it  is  probable  that  the  maximum  depth  of  this  ice- 
sheet  somewhat  exceeded  10,000  feet,  and  that  the  area  of  this  great  depth 
was  a  belt  extending'  eastward  from  a  few  hundred  miles  north  or  northeast 
of  the  south  part  of  Lake  Agassiz  to  a  distance  of  about  1,000  miles  east- 
northeast,  lying  thus  much  i\earer  than  in  the  assumed  ease  of  Mr.  Wood- 
ward's investigation.  The  smaller  area  and  less  total  mass  of  the  ice-sheet 
attracting  Lake  Agassiz  may  have  been  offset  by  the  nearer  position  of  a 
large  part  of  its  mass  than  in  the  assumption  of  the  problem,  so  that 
possibly  its  influence  might  be  as  great  in  producing  an  ascent  of  the  lake 
level  above  the  level  of  the  present  time;  but,  if  this  mathematical  inves- 
tigation is  reliable,  gravitation  of  the  lake  toward  its  ice  barrier  could  not 
give  to  its  highest  shore  a  noi'thward  ascent  of  more  tlian  a  few  inches  per 
mile,  at  the  most  not  so  much  as  half  a  foot,  whereas  its  observed  ascent 
within  the  area  of  my  leveling  attains  a  maximum  rate  of  1  foot  to  16 
inches  per  mile,  and  this  belongs  to  a  north-northeastward  ascent  of  fully 
IJ  feet  per  mile.  A  quarter  part,  or  probably  less,  of  the  changes  in  the 
levels  of  these  beaches  is  therefore  referable  to  ice  attraction,  while  the 

'U.  S.  Geol.  Survey,  Sixtli  Annual  Report,  for  1884-85,  pp.  291-300;  aud  Bulletin  No.  48,  "On  the 
form  iind  position  of  the  sea  level,"  1888,  p.  88.  Compare  also  Prof.  Edward  Hull's  computations, 
"  On  the  eifect  of  continental  lands  in  altering  the  level  of  the  adjoining  oceans,"  Geol.  Magazine  (3), 
Vol.  V,  pp.  113-115,  March,  1888;  "Polar  ice-caps  aud  their  influence  in  changing  sea  levels,"  by  Sir 
William  Thomson,  Trans.,  Geol.  Society  of  Glasgow,  Vol.  VIII,  1888,  pp.  322-340;  and  "The  study  of 
the  earth's  figure  by  means  of  the  pendulum,"  by  E.  D.  Preston,  Am.  Jour.  Sci.  (3),  Vol.  XLI,  pp. 
445-460,  June,  1891. 


CRUSTAL  CHANGES  IN  TEMPERATUEB.  491 

remaining  three-quarters,  or  a  larger  part,  amounting  at  least  to  about  130 
to  300  feet,  from  south  to  north,  in  southwestern  Manitoba,  belongs  to  a 
differential  elevation  of  the  land. 

CHANGES    IN    THE    TEMPERATURE    OF    THE    EARTH'S    CRUST. 

Among  the  conditions  producing  changes  in  the  height  and  slopes  of 
the  land  on  which  Lake  Agassiz  lay  are  the  cooling  and  contraction  of  the 
earth's  crust  by  the  ice-sheet  and  glacial  waters,  and  the  subsequent  warm- 
ing and  expansion  owing  to  the  amelioration  of  the  climate.  The  supei^ficial 
portion  of  the  earth's  crust  in  the  Red  River  Valley  has  a  temperature  of 
47°  to  42°  F.,  as  shown  by  the  water  of  artesian  wells  situated  respectively 
at  Ada  and  Donaldson,  Minn. '  But  during  the  time  when  this  district  was 
covered  by  the  ice-sheet  the  temperature  of  the  underlying  land  surface 
was  reduced  to  the  freezing  point,  32°  F.,  and  a  similar  lowering  of  tem- 
perature may  have  affected  the  crust  to  a  considerable  depth,  largely  through 
the  influence  of  percolating  water,  causing  a  slight  depression  of  the  isogeo- 
tlierms,  with  consequent  contraction  of  the  rocks  and  lowering-  of  the  land 
surface.  By  comparison  with  the  present  mean  annual  temperature  of  the 
Red  River  Valley,  ranging  approximately  from  41°  at  Lake  Traverse  to  33° 
at  Winnipeg,  ^  it  is  evident  that  the  artesian  waters  before  noted  receive  part 
of  their  heat  from  the  earth's  interior.  In  like  manner  probably  the  interior 
heat  kept  the  superficial  portion  of  the  earth's  crust  beneath  the  ice-sheet 
as  warm  as  32°,  at  which  temperature  the  earth's  heat  would  be  continually 
melting  the  ice,  though  certainly  at  a  very  slow  rate. 

The  differences  in  the  temperatures  of  the  earth's  crust,  due  to  the 
ice-sheet  and  to  water  permeating  downward  from  it,  would  not,  therefore, 
probably  exceed  15°  from  that  of  the  present  time  in  the  southern  part  of 
the  basin  of  Lake  Agassiz,  and  would  decrease  to  10°  at  Donaldson,  in 
Kittson  County,  the  most  northwestern 'in  Minnesota,  and  to  even  a  less 
amount  at  Winnijjeg.      The  extent  to  which  these  slight  changes  in  the 

'  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Eleventh  Annual  Report,  pp.  147, 148.  Detailed 
descriptious  of  these  wells  are  given  in  the  next  chapter. 

-  C.  A.  .Sohott  in  Smithsonian  Contributions  to  Knowledge,  Vol.  XXI,  1876 ;  Atlas  of  the  Tenth 
Census  of  the  United  States;  Report  of  the  Department  of  Agriculture  and  Statistics  of  M.initoba 
for  1882,  p.  318.  Also  see  Chapter  XI  for  statements  of  the  monthly  and  mean  annual  temperature  at 
this  district. 


492  ■  THE  GLACIAL  LAKE  AGASSIZ. 

crustal  temperatures  would  depress  the  land  while  it  was  ice-covered  and 
raise  it  when  the  ice  was  withdrawn  depends  on  the  ratios  of  contraction 
and  expansion  of  the  underlying  rocks.  These  ratios  have  been  experi- 
mentally determined  in  the  case  of  various  building  stones,  and  computations 
therefrom  indicate  that  only  a  very  small  amount  of  subsidence  and  eleva- 
tion of  the  land  could  be  caused  in  this  way.^  The  total  elevation  so 
produced  was  probably  not  more  than  50  feet  in  the  southern  part  of  the 
Red  River  Valley,  and  not  more  than  30  feet  at  Winnipeg;  and  its  slight 
differential  effect  would  be  in  the  opposite  direction  to  that  which  has  given 
to  the  beaches  of  Lake  Agassiz  their  northward  ascent.  This  element  in 
the  causation  of  the  changes  of  elevation  appears  to  be  comparatively 
insignificant  in  itself,  and  its  small  component  in  the  oscillation  of  the  shore- 
lines would  be  opposed  to  that  for  wliich  we  are  seeking  an  explanation. 

EPEIROGENIC    MOVEMENTS    APPARENTLY    DEPENDENT    ON    GLACIATION. 

It  seems  to  be  very  clearly  indicated  by  the  gradual  diminution  in  the 
northward  ascent  of  the  beaches,  until  the  lowest  and  latest  have  nearly 
the  level  of  the  present  time,  that  these  progressive  changes  of  elevation 
were  directly  dependent  upon  the  departure  of  the  ice-sheet,  with  which 
great  geologic  event  they  were  contemporaneous.  As  already  noted  in 
Chapter  V  and  on  a  foregoing  page  of  this  chapter,  these  changes  were  so 
directly  proportionate  with  the  glacial  recession  that  the  northward  ascents 
of  the  successive  beaches  were  at  first  refen-ed  to  the  diminishing  gravi- 
tation of  the  lake  toward  the  ice-sheet;  but,  apart  from  the  inadequacy  of 
this  cause,  determined  by  Mr.  Woodward's  investigations,  the  great  extent 
of  the  highest  beach  and  its  relation  to  terminal  moraines  marking  stages  in 
the  glacial  recession  sufficiently  demonstrate  that  other  causes  contributed 
even  more  than  ice  attraction  to  produce  the  changes  observed  in  the  levels 
of  the  beaches. 

There  remain  to  be  considered,  as  probable  causes,  first,  the  relation- 
ship between  the  earth's  crust  and  its  interior  which  may  have  permitted  a 

'  T.  C.  Chamberliu  iq  Sixth  Annnal  Report,  U.  S.  Geol.  Survey,  p.  302,  and  in  paper  read  before 
the  Philosophical  Society,  Washington,  March  13,  188G;  G.  K.  Gilbert  in  Am.  .lonr.  Sci.  (3),  Vol. 
XXXI,  p.  297,  April,  1886,  and  in  U.  S.  Geol.  Survey,  Monograph  I,  "Lake  Bonneville,"  pp.  377,378. 


EELATION   OF  THE  EAETH'S  CEUST  AND  INTEEIOR.  493 

sinking  of  the  crust  beneath  the  vast  weight  of  the  ice-sheet  and  a  reeleva- 
tiou  when  that  weight  was  removed,  and,  second,  oscillations  which  may 
have  occurred  without  dependence  on  the  glaciation.  For  the  discrimination 
of  these  movements  it  will  be  very  instructive  to  notice  the  changes  of 
elevation  that  have  been  going  forward  at  the  same  time  in  other  parts 
of  the  North  American  and  European  glaciated  regions,  and  also  in  vari- 
ous areas  which  were  never  thus  ice-laden.  If  Lake  Agassiz  is  found  to 
be  an  instance  where  nearly  all  these  changes  are  apparently  referable  to 
glaciation,  there  will  be  no  lack  of  opportunity  for  comparing  it  with  other 
regions  where  the  effects  due  to  glaciation  are  combined  with  independent 
crustal  movements. 

Discussion  of  the  relationship  of  the  eartli's  crust  to  the  interior. — My 
former  reference  of  the  northward  ascent  of  the  beaches  of  Lake  Agassiz 
to  ice  attraction,  with  the  assmnption  that  the  earth  was  so  rigid  that  its 
form  would  not  be  changed  by  the  load  of  the  ice-sheet  nor  liy  its  removal, 
seemed  more  probable  because  of  the  well-known  physical  and  mathe- 
matical researches  of  Hopkins,  Thomson,  Pratt,  and  Prof.  G.  H.  Darwin, 
who  conclude  that  the  earth  is  probably  solid,  with  not  less  rigidity  than 
that  of  glass  or  of  steel.  In  deference  to  their  investigations,  this  con- 
clusion is  accepted  and  taught  in  recent  text-books  of  geology  by  A. 
Geikie  and  Le  Conte ;  ^  but  in  similarly  recent  text-books  Prestwich  and 
Dana  teach  that  the  earth  probably  consists  of  a  comparatively  thin  crust, 
underlain  by  a  molten  interior,  which  may  change  within  a  moderate  depth 
to  a  great  imcleal  solid  mass.  Among  other  geologists  and  physicists  who 
have  discussed  the  conditions  of  the  earth's  interior.  King,  ^  Shaler,^  and 

'  Since  the  publication  of  Le  Conte's  Elements  of  Geology,  revised  second  edition,  1882,  this 
eminent  geologist  has  abandoned  tlie  opinion  here  noted,  and  now  believes  "that  the  general 
structure  of  the  earth  is  that  of  a  solid  nucleus  constituting  nearly  its  whole  mass,  a  solid  crust  of 
inconsiderable  comparative  thicliness,  and  a  subcrust  liquid  layer,  either  universal  or  over  large 
areas,  separating  the  one  from  the  other.  »  »  *  Also  that  the  crust  rests  upon  the  subcrust  liquid 
as  a  floating  body."  American  Geologist,  Vol.  IV,  pp.  38^4,  July,  1889;  Am.  Jour.  Sci.  (3),  Vol. 
XXXVIII,  pp.  257-263,  Oct.,  1887;  Elements  of  Geology,  third  edition,  1891,  pp.  84-87,  264. 

^U.  S.  Geological  Exploration  of  the  Fortieth  Parallel,  Vol.  I,  Systematic  Geology,  1878,  pp.  117, 
696-725. 

^'Proc.,  Boston  Soc.  Nat.  Hist.,  1866,  Vol.  XI,  pp.  8-15;  1868,  Vol.  XII,  pp.  128-136;  1874,  Vol. 
XVII,  pp.  288-292.  Memoirs,  Boston  Soc.  Nat.  Hist.,  1874,  Vol.  U,  pp.  320-340.  Scribuer's  Magazine, 
Vol.  Ill,  pp.  201-226,  Feb.,  1888. 


494  THE  GLACIAL  LAKE  AGASSIZ. 

Reade^  believe  it  to  be  solid,  while  Whitney,"^  Button,^  Powell,'*  Wads- 
wortli,^  Crosby,*'  Claypole,'  Phillips,*  Airy,"  Fisher,"  aud  Jamieson" 
believe  that  it  is  molten,  or  at  least  is  surrounded  by  a  molten  layer, 
and  that  the  earth's  crust  floats  in  a  condition  of  isostasy^^  or  gravitational 
equilibrium  upon  the  heavier  liquid  or  viscous  mobile  interior  or  layer 
enveloping  the  interior,  subject,  however,  to  stresses  and  resulting  defor- 
mation because  of  the  earth's  contraction.  The  thickness  of  the  crust, 
according  to  this  hypothesis,  is  variously  estimated  to  be  from  20  to  50 
miles,  or  possibly  100  miles  or  more. 

Another  statement  of  the  probable  relationship  of  the  earth's  crust  to 
the  interior,  which  seems  to  come  between  these  diverse  opinions  and  in 
some  measure  to  express  the  important  features  of  each,  is  given  as  follows 
by  Gilbert,  in  his  discussion  of  faults  and  displacements  of  the  Wasatch 
range  and  the  area  of  Lake  Bonneville : 

We  are  forced  to  conclude  that  the  mountain  ranges  of  the  Bonneville  basin 
and  the  valleys  between  them  do  not,  with  reference  to  each  other,  obey  the  law  of 
flotation. 

It  follows  with  equal  cogency  that  the  faults  do  not  penetrate  to  a  layer  charac- 
terized by  fluidity  or  semi-fluidity,  implying  by  these  terms  the  power  to  flow  under 
small  shearing  strain,  but  terminate  in  a  region  of  rigidity,  implying  by  that  term 
the  ability  to  withstand  relatively  large  shearing  strain.  I  conceive  them  to  termi- 
nate at  the  upper  limit  of  the  region  of  plasticity  by  pressure,  implying  by  that 
phrase  that  at  and  below  a  certain  depth  the  rocks  of  the  crust,  however  rigid,  are 

'  The  Origin  of  Mountain  Ranges,  1886,  pp.  6,  7,  256,  267,  270,  etc.  Philosophical  Magazine,  June, 
1891  (also  in  Am.  Geologist,  Nov.,  1891). 

2  Earthquakes,  Volcanoes,  and  Mountain  Building,  1871,  pp.  77-87. 

3  Penn  Monthly,  Vol.  VII,  pp.  364-378,  and  417-431,  May  aud  June,  1876.  U.  S.  Geol.  Survey,  Fourth 
Annual  Report,  pp.  183-198;  Sixth  Annual  Report,  pp.  195-198. 

■I  Science,  Vol.  Ill,  pp.  480-482,  April  18,  1884.     The  Forum,  Vol.  II,  pp.  370-391,  Dec,  1886. 

^Am.  Katuralist,  Vol.  XVIII,  June,  July,  and  August,  1884. 

«Proc.,  Boston  Soc.  Nat.  Hist.,  1883,  Vol.  XXII,  pp.  443-485.  Geol.  Magazine  (2),  Vol.  X,  1883, 
pp.  241-252. 

■'  Am.  Naturalist,  Vol.  XIX,  pp.  257-268,  March,  1885.  Am.  Geologist,  Vol.  I,  pp.  382-386,  and  Vol.  II, 
pp.  28-35,  June  and  July,  1888. 

8  Vesuvius,  1869,  pp.  324,  329. 

9  Nature,  Vol.  XVIII,  pp.  41-44,  May  9, 1878. 

10  Physics  of  the  Earth's  Crust,  1881,  pp.  223,  270,  etc. 

11  Geol.  Magazine  (3),  Vol.  IV,  1887,  pp.  344-348. 

I!' A  term  proposed  by  Capt.  C.  E.  Button  in  a  paper  "On  some  of  the  greater  problems  of  physical 
geology,"  Bulletin  of  the  Philosophical  Society  of  Washington,  Vol.  XI,  pp.  51-61,  April  27, 1889.  See 
also  an  important  discussion  of  this  condition  of  the  earth's  crust,  "The  Gulf  of  Mexico  as  a  measure 
of  isostasy,"  by  W  J  McGee,  in  Am.  Jour.  Sci.  (3),  Vol.  XLIV,  pp.  177-192,  Sept.,  1892. 


CONDITION  OF  THE   INTEHIOE  OF  THE   EARTH.  495 

subject  to  such  x3ressiire  that  their  yieldiug  under  shearing  strains  exceeding  the 
elastic  limit  is  not  by  fracture,  but  by  iiow.  I  conceive  the  orogenic  bloclis  as  con- 
fluent with  the  subjacent  layer,  excepting  such  as  may  wedge  out  by  the  convergence 
of  fault  planes.i 

This  view  is  closely  allied  with  that  which  regards  the  interior  as  solid, 
and,  indeed,  if  I  understand  the  authors  holding'  the  doctrine  of  solidity, 
forms  a  necessary  postulate  of  their  explanation  of  orogenic  and  epeiro- 
genic  movements.  It  is  again  well  stated  by  Becker,  who  regards  the  earth 
"as  a  solid  mass  of  extremely  high  viscosity  which  would  yield  slowly  to 
relatively  moderate  forces  of  constant  terrestrial  direction  and  long  dura- 
tion, but  which  would  probably  yield  almost  imperceptibly  to  any  force 
of  brief  duration  or  ra2:)idly  changing  direction.""  For  such  a  condition, 
however,  which  seems  to  me  probably  or  possibly  true  for  all  the  earth 
excepting  its  volcanic  areas,  I  should  prefer,  as  more  intelligible  to  ordi- 
nary readers,  to  speak  of  the  interior  as  plastic  rather  than  as  either  solid 
or  liquid,  though  in  its  rigidity  or  resistance  to  change  of  form  it  may 
equal  or  surpass  the  hardest  rocks  of  the  earth's  surface. 

In  the  present  state  of  our  knowledge,  the  elevation  of  the  area  of 
Lake  Agassiz,  increasing  in  amount  from  south  to  north,  during  the  depart- 
ure of  the  ice-sheet,  seems  most  clearly  intelligible  by  supposing  it  to  have 
been  an  uplifting  of  the  crust  by  the  inflow  of  plastic  if  not  perfectly 
molten  rock  from  districts  outside  the  glaciated  area,  occurring  probably 
between  the  depths  of  20  and  100  miles,  in  obedience  to  gravitation, 
which,  to  preserve  the  condition  of  isostasy,  Avould  cause  the  crust,  when 
loaded  by  the  ice-sheet,  to  sink  and  displace  part  of  the  plastic  interior,  and 
when  the  ice-sheet  was  removed  would  cause  the  plastic  rock  to  flow  back 
and  raise  the  crust  approximately  to  its  former  height. 

It  must  be  confessed  that  we  have  only  a  very  inadequate  knowledge 
of  the  conditions  which  would  result  from  the  enormous  pressure  and  high 
temperature  of  the  earth's  interior;  and  wide  diversity  in  specidations  on 
this  subject  will  probably  long  continue.  Professor  Shaler,  while  holding 
that  the  earth  is  mainly  solid  throughout,  perhaps  having  in  its  most  mobile 
layer  beneath  the  crust  "a  rigidity  such  as  belongs  to  the  metals  of  average 

>  U.  S.  Geol.  Survey,  Monograph  I,  Lake  BonneviUe,  1890,  pp.  358, 359. 
''Bulletin,  G.  S.  A.,  Vol.  II,  1891,  p. 70. 


496  THE  GLACIAL  LAKE  AGASSIZ. 

resistance  to  compression,"  yet  is  one  of  the  earliest  and  most  decided  advo- 
cates of  the  opinion  that  the  weight  of  an  ice-sheet  may  depress  the  area  on 
which  it  hes,  and  that  the  departure  of  the  ice  would  be  attended  by  reele- 
vation.  In  comparison,  however,  with  the  physical  conditions  and  laws 
familiar  to  us  upon  the  earth's  surface,  the  subsidence  and  elevation  of 
extensive  areas,  as  of  nearly  all  glaciated  regions,  seem  to  demonstrate  a 
mobility  of  the  earth's  interior  as  if  it  were  fused  rock.  The  same  conclu- 
sion is  indicated  by  volcanoes,  which  are  probably  the  openings  of  molten 
passages  that  communicate  downward  through  the  crust  to  a  heavier  melted 
portion  of  the  interior,  thence  deriving  their  supply  of  heat,  while  their 
outpoured  lavas  consist  largely  or  wholly  of  fused  portions  of  the  crust,  the 
phenomena  of  eruption  being  caused  by  the  access  of  water  to  the  upper 
part  of  the  molten  rock,  near  the  volcanic  vent.  But  the  great  plications  of 
the  strata  in  the  formation  of  mountain  chains  evidently  involve  only  the 
upper  part  of  the  earth's  crust,  crumpled  into  smaller  area  in  adapting  itself 
to  the  diminishing  voluuie  of  the  lower  portion  of  the  same  crust,  which, 
with  the  nucleus,  is  undergoing  contraction  on  account  of  the  gradual  loss 
of  its  heat,  and  perhaps  also  on  account  of  progressing  solidification  and 
compression.  There  is  in  this  process  no  dependence  on  the  plastic  or 
perhaps  molten  condition  of  the  interior,  except  as  that  seems  to  be  necessary 
for  distortion  of  the  earth,  both  of  the  crust  and  nucleus  or  mobile  layer 
enveloping  the  nucleus,  whereby  considerable  shrinliage  of  volume  can 
take  place  before  the  accumulated  stress  becomes  sufficient  for  the  forma- 
tion of  a  mountain  chain.  At  the  present  time  depressions  and  elevations, 
probably  caused  by  accumulating  stresses,  are  slowly  changing  the  relations 
of  land  and  sea  upon  many  parts  of  the  earth's  surface.  In  the  same  way 
the  downward  and  upward  movements  which  would  be  caused  by  the 
burden  of  the  ice-sheet  and  its  removal  are  doubtless  in  many  places  com- 
plicated by  concomitant  or  subsequent  movements  thus  due  to  deformation 
under  stresses,  by  which  the  elevation  attributable  to  the  departure  of  the 
ice-sheet  may  be  augmented  or  partly  or  wholly  counteracted,  giving  much 
irregularity  to  the  glacial  and  postglacial  oscillations  of  the  land. 

The  area  of  Lake  Bonneville  has  experienced  changes  of  level  since 
the  formation  of  its  highest  shore-line,  which  Mr.  Gilbert  finds  to  be  in  har- 


CRUST  DEFOEMATION  BY  THE  ICE-SHEET.  497 

mony  with  the  explanation  that  they  were  due  to  the  evaporation  of  the 
lake  and  the  consequent  partial  restoration  of  equilibrium  by  the  underflow 
of  plastic  rock;  but  he  regards  his  observations  as  too  incomplete  to  furnish 
absolute  proof  of  this  hypothesis.'  A  supplementary  and  more  satisfactory 
test  is  supplied  by  this  survey  of  Lake  Agassiz.  Debarred  from  referring 
the  northward  ascent  of  the  beaches  of  this  glacial  lake  chiefly  to  ice 
attraction,  I  regard  my  observations  of  their  increasing  rate  of  ascent  in 
proceeding  from  south  to  north,  the  gradual  approximation  in  the  lower 
beaches  toward  horizontality,  and  the  probable  completion  of  these  changes 
in  relative  elevation  during  the  existence  of  Lake  Agassiz  and  the  depart- 
ure of  the  ice-sheet,  as  all  strikingly  accordant  with  this  explanation,  and, 
indeed,  as  demonstrative  of  its  truth.  These  changes  in  the  levels  of  the 
beaches  of  Lake  Agassiz,  partly  pertaining  to  the  lake  itself  and  in  larger 
part  to  the  crust  of  the  earth,  are  thus  believed  still  to  be  wholly  referable 
to  the  influence  of  the  ice-sheet  in  its  recession,  with  which  they  show 
such  remarkable  correspondence  in  the  direction,  character,  and  gradual 
decrease  of  the  northward  ascent.  No  irregularities  of  the  differential 
changes  in  elevation  are  found  which  seem  to  require  other  explanation,  the 
rise  caused  by  the  removal  of  the  ice-sheet  not  being  combined  upon  this 
area,  so  far  as  can  be  detei'mined,  with  independent  earth  movements  either 
of  elevation  or  depression. 

History  of  the  doctrine  of  crust  deformation  hy  the  ice-sheet. — Jamieson 
appears  to  have  been  the  first,  in  1865,  to  suggest  this  view,  which  I 
receive  from  him,  that  the  submergence  of  glaciated  lands  when  they 
were  loaded  with  ice  has  been  caused  directly  by  this  load  pressing  down 
the  earth's  crust  upon  its  fused  interior,  and  that  the  subsequent  reeleva- 
tion  was  a  hydi'ostatic  (or  we  may  better  say  isostatic)  uplifting  of  the 
crust  by  underflow  of  the  inner  mass  when  the  ice  was  melted  away.^     Two 

>  Am.  Jour.  Sci.  (3),  Vol.  XXXI,  pp.  284-299,  April,  1886.  U.  S.  Geo!.  Survey,  Monograph  I,  Lake 
Bonneville,  1890,  pp.  379-392. 

-Quart.  Jour.  Geol.  Soc,  Vol.  XXI,  p.  178.  Later  discussions  of  this  subject  by  Mr.  Jamieson  are 
in  the  Geological  Magazine  (2),  Vol.  IX,  pp.  400-407  and  4,57-466,  Sept.  and  Oct.,  1882;  and  (3),  Vol. 
IV,  pp.  344-348,  Aug.,  1887.  In  the  article  last  cited  he  applies  this  explanation  to  the  changes  of  the 
beaches  of  Lake  Agassiz,  which  up  to  that  time  I  had  attributed  mainly  to  ice  attraction.  The  same 
principle,  however,  vras  brought  forward  by  Sir  John  Herschel  in  1836,  and  had  been  advocated  by 
Prof.  .James  Hall,  of  New  York,  in  1859,  in  attributing  to  the  weight  of  sediments  the  long-continued 
subsidence  of  the  areas  on  which  they  have  been  deposited  in  great  thickness. 

MON  XXV 32 


498  THE  GLACIAL  LAKE  AGASSIZ. 

years  later  Whittlesey  published  a  similar  opiuiou.'  lu  1868  Shaler  referred 
the  subsidence  of  ice-covered  areas  to  a  supposed  rise  of  isogeothermal  lines 
in  the  subjacent  crust,  oiDeratiug,  in  conjunction  with  the  ice-sheet,  to  pro- 
duce downward  flexure;"  but  in  1874  and  later  he  regards  the  depression  as 
due  directly  to  the  weight  of  the  ice,  and  the  reelevation  as  due  to  its 
removal.^  The  same  view  is  advanced  also  by  Chamberlin  to  account  for 
the  basins  of  the  Laurentian  lakes,  where  he  believes  a  considerable  part  of 
the  glacial  depression  to  have  been  permanent/ 

Tardiness  in  the  he  (finning  of  the  changes  of  levels  of  the  Lake  Agassiz 
basin. — That  the  greater  part  of  the  changes  of  levels  upon  the  area  of 
Lake  Agassiz  has  been  due  to  differential  elevation  of  the  earth's  crust, 
mstead  of  ice  attraction,  seems  to  be  proved  by  the  tardiness  of  their 
beginning,  as  shown  by  the  relationship  of  the  highest  beach  of  Lake 
Agassiz  to  the  contiguous  terminal  moraines  formed  on  the  adjacent  land 
areas  during  the  recession  of  the  ice-sheet,  of  which  a  detailed  description 
has  been  given  in  Chapter  IV.  The  highest  beach  is  continuous  on  the 
east  from  Lake  Traverse  about  140  miles  north  to  Maple  Lake,  which  is  as 
far  as  exact  exploration  of  it  has  been  carried.  On  the  west  this  shore-line 
is  unbroken  along  an  extent  of  about  250  miles  from  south  to  north,  reach- 
ing into  Manitoba.  Now  the  adjacent  Dovre,  Fergus  Falls,  Leaf  Hills,  and 
Itasca  moraines  appear  to  have  been  successively  accumulated  duiing  the 
time  of  formation  of  this  single  highest  beach,  which  marks,  through  so 
great  distances  and  so  large  a  portion  of  the  glacial  recession,  a  nearly  or 
quite  unvarying  stage  of  the  lake  and  undisturbed  repose  of  the  earth's 
crust.  If  diminishing  gravitation  of  the  water  of  the  lake  toward  the  ice- 
sheet  had  been  the  chief  cause,  or  even  an  element  of  large  importance 
among  component  causes,  of  the  changes  of  levels  of  the  beaches,  the 
surface  of  the  lake  must  have  fallen  considerably  in  its  northern  portion 

'Proc,  A.  A.  A.  S.,  Vol.  XVI,  pp.  92-97. 

^Troc,  Boston  Soc.  Nat.  Hist.,  Vol.  XII,  pp.  128-136. 

sproc,  Boston  Soc.  Nat.  Hist.,  Vol.  XVII.  pp.  288-292;  Memoirs,  Boston  Soc.  Nat.  Hist.,  Vol.  II, 
pp.  335-340.  Am.  Jour.  Sci.  (3),  Vol.  XXXIII,  pp.220,  221,  March,  1887.  Scribner's  Magazine,  Vol.  I, 
p.  259,  March,  1887. 

'Geology  of  Wisconsin,  Vol.  I,  1883,  p.  290;  Proc,  A.  A.  A.  S.,  Vol.  XXXII,  1883,  p.  212.  The 
problems  of  ice  attraction  and  of  deformation  of  the  earth's  crust  have  been  further  discussed  by- 
Professor  Chamberlin  before  the  Philosophical  Society  of  Washington,  March  13, 1886;  and,  jointly  with 
Professor  Salisbury,  in  the  Siitli  Annual  Report,  U.  S.  Geol.  Survey,  pp.  291-304. 


PAUSES  IN"  THE   CEUSTAL  UPLIFT.  499 

because  of  the  decreasing  attraction,  of  the  ice  during  the  stages  of  its 
retreat  between  these  moraines.  But  the  extent  of  the  highest  beach 
shows  that  no  appreciable  changes  of  level  took  place  while  the  ice-sheet 
was  being  melted  back  250  miles  or  more  and  was  probably  much  reduced 
in  thickness  upon  a  large  area  farther  north,  meanwhile,  at  times  of  halt  in 
its  recession,  or  pei'haps  of  some  readvance,  accumulating  the  most  massive 
morainic  deposits  of  this  region.  The  stability  of  the  crust  had  been  main- 
tained during  this  great  reduction  of  the  ice  pressure;  and  when  at  length 
an  uplift  ensued,  the  process  was  slow  and  marked  by  no  paroxysmal 
action,  but  progressed  in  a  gradual  manner,  though  yet  with  pauses,  as  was 
also  doubtless  the  method  of  the  continued  retreat  of  the  ice. 

Pauses  in  the  crustal  uplift  recorded  hy  the  series  of  beaches. — The  suc- 
cessive beaches  of  Lake  Agassiz,  numbering  seventeen  in  its  northern  part 
while  the  lake  outflowed  southward  by  the  river  Warren,  and  fourteen 
while  it  outflowed  northeastward,  appear  to  have  been  formed  dm-ing 
pauses  in  the  differential  elevation  of  this  area.  Between  the  times  of 
formation  of  the  beaches  the  uplift  of  the  land  was  too  rapid  to  be  recorded 
by  wave  erosion  and  beach  deposits,  and  the  definitely  marked  shore-lines 
belong  to  stages  of  interruption  or  slower  progress  of  this  crustal  uplift. 

At  the  southern  end  of  the  lake  each  of  the  beaches,  into  which  several 
in  their  course  from  north  to  south  become  merged,  may  belong  to  a  slowly 
sinking  lake  surface,  with  change  of  5  feet,  or  in  some  cases  10  feet,  during 
the  accumulation  of  the  single  beach  ridge;  and  the  intervals  of  10  or  15 
feet  between  the  levels  held  by  the  mouth  of  the  lake  while  the  beaches  of 
its  southern  part  were  being  formed  appear  to  represent  times  of  exception- 
ally rapid  erosion  because  of  comparatively  fast  elevation  of  that  area  and 
of  the  country  crossed  by  the  River  Warren.  Along  the  course  of  this 
stream,  the  present  valley  of  the  Minnesota  River,  no  outcropping  rocks 
are  found  at  so  high  levels  that  they  would  be  touched  by  the  continuation 
of  the  planes  of  the  upper  beaches  of  Lake  Agassiz,  having  in  their 
southern  part  a  descent  to  the  south  of  about  a  half  of  a  foot  per  mile. 
The  River  Warren  cut  its  channel  wholly  in  glacial  di-ift,  until  during  the 
McCauleyville  stages  of  the  lake  it  reached  the  ledges  of  granitoid  gneiss 


500  THE  GLACIAL  LAKE  AGAiSSIZ. 

which  outcrop  in  the  bottom  of  the  valley  along  a  distance  of  several  miles 
next  below  Big  Stone  Lake. 

Changes  in  levels  of  the  beaches  only  a  partial  measure  of  the  ice  iveight. — If 
the  thickness  of  the  ice-sheet  upon  the  area  of  Lake  Agassiz  was  a  half 
mile  to  IJ  miles,  as  seems  probable,  increasing  from  south  to  north  and 
northeast,  the  crustal  uplift  measuring  the  inflow  to  this  area  of  an  equal 
weight  of  plastic  or  molten  rock  would  range  from  880  feet,  or  a  sixth  of 
a  mile,  at  Lake  Traverse,  on  the  south,  to  2,640  feet,  or  a  half  mile,  at 
the  north  end  of  Lake  Winnipeg,  on  the  assumption  that  the  density  of  the 
inflowing  rock  or  magma  were  that  of  the  upper  portion  of  the  earth's 
crust.  The  density  of  ice  is  taken  as  0.9,  water  being  1.0;  and  that  of  the 
rocks  forming  the  earth's  surface  is  assumed  to  average  2.7,  the  earth's 
mean  density,  determined  by  three  independent  methods  with  closely 
accordant  results,  being  about  5.5.  But  the  mobile  stratum  next  beneath 
the  solid  crust  is  surely  somewhat  heavier  than  the  crust.  Comparison  of 
the  earth's  supei-ficial  and  mean  densities  indicates  for  this  magma  a  proba- 
ble density  of  3.5  or  more,  which  would  reduce  the  computed  uplift  to  680 
feet  at  the  south,  with  increase  of  about  2  feet  per  mile  northward  to  2,040 
feet,  in  round  munbers  2,000  feet,  at  the  mouth  of  Lake  Winnipeg  and 
along  the  Nelson  River,  or  less  than  these  amounts  if  the  density  of  the 
uplifting  magma  was  greater  than  3.5.  It  is  very  probable  that  the  sub- 
sidence caused  by  the  ice-sheet,  depressing  the  crust  below  its  preglacial 
height,  was  more  than  Avould  be  thus  strictly  proportionate  to  the  weight 
added  by  the  ice  accumulation;  but  on  the  other  hand  it  seems  probable, 
as  shown  by  the  northward  ascent  of  the  beaches  of  Lake  Agassiz,  that 
only  a  minor  fraction,  perhaps  nowhere  within  this  basin  exceeding  one- 
fom-th,  of  the  weight  of  ice  removed  was  compensated  by  the  diflPerential 
uplift  of  the  land. 

But  could  we  well  explain  the  facts  of  glacial  striation  and  drift  trans- 
portation by  assuming  for  the  ic«-sheet  a  less  thickness,  as  one-third  of  a 
mile  to  1  mile  from  sovith  to  north  upon  the  lacustrine  area,  which  may, 
indeed,  be  nearer  the  truth,  the  rate  of  ascent  of  the  shore-lines  within  the 
area  of  my  survey,  resulting  apparently  from  the  departure  of  the  ice, 
would  be  closely  in  accordance  with  the  hypothesis  that  the  earth's  crust  is 


PREGLACIAL   ELEVATION   SHOWN  BY  PJOKDS.  501 

floating-  in  isostatic  equilibrium  upon  a  plastic  or  molten  interior,  though 
the  vertical  extent  of  elevation  of  the  whole  basin  is  probably  several  hun- 
dred feet  less  than  would  be  expected  as  a  full  measure  of  the  weight 
removed.  Even  with  the  presumption  that  the  uplift  in  its  rate  of  increase 
toward  the  north  is  only  approximately  half,  and  in  its  aggregate  amount 
only  a  qiiarter  part,  or  less,  of  what  computation  would  require,  this 
hypothesis  still  seems  to  aftbrd  the  best  explanation  that  we  are  able  to 
offer  for  the  northward  ascent  of  these  beaches,  beyond  such  small  por- 
tion as  can  be  referred  to  ice  attraction.  And  it  is  to  be  observed  that 
glaciated  areas  generally  show  by  their  fjords  that  part  of  their  depression 
by  the  ice-sheet  continues  to  the  present  time,  not  having  been  equaled  by 
the  crustal  elevation  when  the  ice-sheet  was  dissolved. 

REVIEW    OP    PLEISTOCENE    OSCIEEATIONS   OF    LAND    AND    SEA. 

Having  thus  examined  the  probable  causes  of  the  changes  in  relative 
elevations  within  the  area  of  Lake  Agassiz,  we  shall  gain  much  further 
knowledge  of  the  evidence  supporting  the  hypothesis  concerning  the  earth's 
crust  and  interior,  to  which  it  has  led  us,  by  reviewing  the  oscillations  that 
have  affected  various  other  parts  of  the  world  contemporaneously  with  the 
accumulation  and  disappearance  of  the  Pleistocene  ice-sheets.  Fjords, 
fossiliferoixs  marine  deposits,  and  migrations  of  animals  and  plants  bear 
important  testimony  of  these  vicissitudes  of  land  and  sea.  It  will  be  well 
first  to  consider  our  own  continent,  and  afterward  to  inquire  whether  South 
America  and  Europe  fared  similarly. 

PREGLACIAL  ELEVATION  OP  NORTH  AMERICA  SHOWN  BY  FJORDS  AND 
SUBMARINE  RIVER  VALLEYS. 

One  of  the  most  interesting  fjords  of  North  America  is  that  of  the 
Saguenay,  tributary  to  the  St.  Lawrence.  Along  a  distance  of  about  50 
miles  the  Saguenay  is  from  300  to  840  feet  deep  below  the  sea-level;  its 
adjoining  cliffs  rise  abruptly  in  some  places  1,500  feet  above  the  water; 
and  the  width  of  its  wonderfully  sublime  and  picturesque  gorge  varies  from 
about  a  mile  to  1^  miles.'     This  fjord,  like  the  many  which  indent  our 

'J.  W.  Dawson,  Notes  ou  the  Postplioceue  Geology  of  Canada,  1872,  p.  41. 


502  THE  GLACIAL  LAKE  AGASSIZ. 

eastern  coast  from  Maine  to  Labrador  and  Greenland,  and  our  western 
coast  from  Puget  Sound  to  the  Arctic  Ocean,  was  eroded  by  a  stream  that 
flowed  along-  the  bottom  of  the  gorge  when  it  was  above  the  sea;  and  this 
erosion  was  probably  going  forward  in  the  epoch  immediately  preceding 
the  Ice  age,  for  earlier  subsidence  during  any  period  of  much  length, 
geologically  speaking,  would  have  caused  the  submerged  valley  to  be  filled 
with  sediments.  The  preglacial  elevation  of  the  Saguenay  region  therefore 
appears  to  have  been  at  least  about  1,000  feet  greater  than  now. 

Similarly  it  is  proved  by  the  fjords  of  Maine,  the  eastern  Canadian 
provinces,  and  Newfoundland,  of  Labrador  and  Greenland,  of  the  Arctic 
coasts  of  North  America,  and  the  archipelago  west  of  Baffin  Bay,  and  of 
the  Pacific  coast  from  Alaska  to  Oregon,  that  the  entii'e  extent  of  the 
North  American  glaciated  area  was  considerably  higher  before  than  after 
glaciation. 

But  the  preglacial  altitude  of  this  area  was  much  greater  than  the 
depth  of  the  fjords  which  indent  its  shores.  It  is  more  nearly,  but  proba- 
bly still  only  partially,  measured  by  river  valleys  and  fjords  which  are  now 
entirely  submerged  beneath  the  ocean.  The  submarine  border  of  the  con- 
tinental plateau  to  depths  of  more  than  3,000  feet  is  cut  by  valleys  or 
channels  which  if  raised  above  the  sea-level  would  be  fjords  or  canyons. 
These  can  be  no  other  than  river  courses  eroded  while  the  land  stood  much 
higher  than  now;  and  its  subsidence  evidently  took  place  in  a  late  geologic 
period,  else  the  deposition  of  silt  must  have  obliterated  the  chaiuiels.  For 
this  continent  a  most  impressive  review  of  the  evidences  of  its  lately  far 
greater  height,  as  shown  by  these  submerged  river  courses,  has  been  given 
by  Prof.  J.  W.  Spencer.^ 

According  to  the  United  States  Coast  Siu'vey  charts,  as  noted  by 
Spencer,  the  bottom  of  a  submerged  valley  just  outside  the  delta  of  the 
Mississippi  is  found  by  soundings  at  the  depth  of  3,000  feet.  This  valley 
is  a  few  miles  wide  and  is  bounded  by  a  plain  of  the  sea  bed  from  900  to 
1,200  feet  above  its  floor.  It  thus  appears  that  the  country  north  of  the 
Gulf  of  Mexico  has  been  raised  for  a  short  time  to  a  height  of  not  less  than 

'"The  higli  continental  elevation  preceding  the  Pleistocene  period,"  Bulletin,  6.  S.  A.,  Vol.  I, 
1890,  pp.  65-70;  also  in  the  Geol.  Magazine  (3),  Vol,  VII,  pp.  208-213,  May,  1890. 


PREGLACIAL  ELEVATION  SHOWN   BY  FJORDS,  503 

3,000  feet;  and  it  is  important  to  note  in  passing  that  an  equal  uplift  would 
wholly  close  the  Strait  of  Florida,  2,064  to  3,000  feet  deep,  through  which 
the  Gulf  Stream  now  pours  into  the  North  Atlantic. 

The  continuation  of  the  Hudson  River  Valley  has  been  traced  by 
detailed  hydrographic  surveys  to  the  edge  of  the  steep  continental  slope  at 
a  distance  of  about  105  miles  from  Sandy  Hook.  Its  outermost  25  miles 
are  a  submarine  fjord  3  miles  wide  and  from  900  to  2,250  feet  in  vertical 
depth,  measured  from  the  crests  of  its  banks,  which,  with  the  adjoining  flat 
area,  decline  from  300  to  600  feet  below  the  present  sea-level.  The  deepest 
sounding  in  this  fjord  is  2,844  feet.^ 

In  a  similar  position,  just  inside  the  bathy metric  line  of  100  fathoms 
on  the  submerged  margin  of  the  continental  plateau  off  the  mouth  of  Dela- 
ware Bay,  the  Coast  Survey  soundings  reveal  a  short  fjord  which  has  a 
depth  of  396  fathoms,  or  2,376  feet' 

Again,  the  United  States  Coast  Survey  and  British  Admiralty  charts, 
as  Spencer  states,  record  submerged  fjord  outlets  from  the  Gulf  of  Maine, 
the  Gulf  of  St.  Lawrence,  and  Hudson  Bay,  respectively,  2,664  feet,  3,666 
feet,  and  2,040  feet  below  sea-level.  The  bed  of  the  old  Laurentian  River 
from  the  outer  boundary  of  the  Fishing  Banks  to  the  mouth  of  the  Saguenay, 
a  distance  of  more  than  800  miles,  shown  by  Professor  Spencer's  map,  is 
reached  by  soundings  1,878  to  1,104  feet  in  depth. 

Greenland  is  divided  from  the  contiguous  North  American  continent 
and  archipelago  by  a  great  valley  of  erosion  which  is  estimated  from  sound- 
ings and  tidal  records  to  have  a  mean  depth  of  2,510  feet  below  sea-level 
for  680  miles  through  Davis  Strait,  2,095  feet  for  770  miles  next  northward 
tlu'ough  Baffin  Bay,  and  1,663  feet  for  the  next  55  miles  north  tlirough 
Smith  Strait.^ 

On  the  Pacific  coast  of  the  United  States  Prof  Joseph  Le  Conte  has 
shown  that  the  islands  south  of  Santa  Barbara  and  Los  Angeles,  now  sepa- 
rated from  the  mainland  and  from  each  other  by  channels  20  to  30  miles 

'A.  Lindenkohl,  Report  of  U.  S.  Coast  and  Geodetic  Survey,  for  1884,  pp.  433-438;  Am.  .Tour.  Sci. 
(3),  Vol.  XXIX,  pp.  475-480,  June,  1885,  and  Vol.  XLI,  pp.  489-499,  with  map,  June,  1891.  J.  D.  Dana, 
Am.  Jour.  Sci.  (3),  Vol.  XL,  pp.  42.5-437,  Dec,  1890,  with  map  reduced  from  U,  S,  Coast  Survey  chart. 

2A.  Lindenkohl,  Am.  Jour.  Sci.  (3),  Vol,  XLI,  p.  498. 

'Smithsonian  Contributions  to  Knowledge,  Vol.  XV,  pp.  163,  164. 


504  THE  GLACIAL  LAKE  AGASSIZ. 

wide  and  600  to  1,000  feet  deep,  were  still  a  part  of  the  mainland  during 
the  late  Pliocene  and  early  Pleistocene  periods.^ 

In  laorthern  California  Prof  Gleorge  Davidson,  of  the  United  States  Coast 
Survey,  as  cited  hj  Spencer,  reports  three  submarine  valleys  about  25,  12, 
and  6  miles  south  of  Cape  Mendocino,  sinking  respectively  2,400,  3,120  and 
2,700  feet  below  the  sea-level  where  they  cross  the  lOO-fathom  line  of  the 
marginal  plateau."  If  the  land  here  wei-e  to  rise  1,000  feet,  these  valleys 
would  be  fjords  with  sides  towering  high  above  the  water,  but  still  descend- 
ing beneath  it  to  profound  depths.  The  time  of  great  elevation  permitting 
erosion  of  these  and  a  large  number  of  other  submerged  valleys  of  the 
Californian  coast  is  shown  by  Le  Conte  to  have  been  the  Pliocene  period, 
with  culmination  of  the  uplift  in  the  early  part  of  the  Pleistocene.^ 

Farther  to  the  north,  Puget  Sound  and  the  series  of  sheltered  channels 
and  sounds  through  which  the  steamboat  passage  is  made  to  Glacier  Bay, 
Alaska,  are  submerged  valleys  of  erosion,  now  filled  by  the  sea,  but  sepa- 
rated from  the  open  ocean  by  thousands  of  islands,  the  continuation  of  the 
Coast  Range  of  mountains.  From  the  depths  of  the  channels  and  fjords 
Dr.  G.  M.  Dawson  concludes  that  this  area  had  a  preglacial  elevation  at 
least  about  900  feet  above  the  present  sea-level  during  part  or  the  whole 
of  the  Pliocene  period.* 

The  general  absence  of  Pliocene  formations  along  both  the  Atlantic 
and  Pacific  coasts  of  North  America  indicates,  as  pointed  out  by  Prof.  C. 
H.  Hitchcock,  that  during  this  long  period  all  of  the  continent  north  of  the 
Gulf  of  Mexico  held  a  greater  altitude,  which  from  the  evidence  of  these 
submarine  valleys  is  known  to  have  culminated  in  an  elevation  at  least 
3,000  feet  higher  than  that  of  the  present  time.  Such  plateau-like  uplift 
of  the  continent  appears  to  have  exerted  so  great  influence  on  its  meteoro- 
logic  conditions,  bringing  a  cooler  climate  throughout  the  year,  that  it 
finally  became  enveloped  by  ice-sheets  to  the  southern  limit  of  the  glacial 
strise,  till,  and  moraines,  stretching  from  Nantucket  and  Cape  Cod  to  New 
York  City,  Cincinnati,  St.  Louis,  Bismarck,  and  thence  westward  to  the 

'Bulletin  of  the  California  Academy  of  Sciences,  Vol.  II,  1887,  pp.  515-520. 

2 Ibid.,  Vol.  II,  pp.  26.5-268. 

^Bulletin,  G.  S.  A.,  Vol.  II,  1891,  pp.  323-330. 

■•Canadian  Naturalist,  new  series,  Vol.  VIII,  pp.  241-248,  April,  1877. 


CHAMPLAIjST  SUBMEEGENCE   SHOWlf  BY  MARINE  BEDS.       505 

Pacific  somewhat  south  of  Vancouver  Island  and  Pviget  Sound.  The  thick- 
ness of  the  ice  in  the  region  of  the  White  Mountains  and  Adirondacks  was 
about  1  mile;  and  Dana  has  shown,  from  the  directions  of  striation  and 
transportation  of  the  drift,  that  its  central  portion  over  the  Laurentide 
highlands  between  Montreal  and  Hudson  Bay  had  probably  a  thickness 
of  fully  2  miles.  In  British  Columbia,  according  to  Dr.  Gr.  M.  Dawson's 
observations,  it  covered  mountain  summits  5,000  to  7,(140  feet  above  the  sea.^ 

LATE  GLACIAL  OR   CHAMPLAIN   SUBMERGENCE   SHOWN   BY    FOSSILIFEROUS   MARINE 

BEDS   OVERLYING  THE    TILL. 

While  thus  heavily  ice-laden,  nearly  the  whole  glaciated  area  of  North 
America  sank  below  its  present  level,  but.  for  the  most  part  only  to  a  slight 
amount  in  comparison  with  its  previous  elevation.  Beginning  at  or  near 
a  line  drawn  northeastward  through  New  York  City,  Boston,  and  Nova 
Scotia,  the  extent  of  the  submergence  of  the  land  by  the  sea  at  the  time 
of  the  recession  of  the  ice-sheet,  as  shown  by  fossiliferous  marine  deposits 
overlying  the  till,  increased  from  150  feet  in  southeastern  New  Hampshire, 
and  200  to  300  feet  on  the  coast  of  Maine  and  New  Brunswick,  to  375  feet 
on  the  St.  Lawrence  opposite  to  the  mouth  of  the  Saguenay,  and  560  feet  at 
Montreal.  It  was  300  to  400  feet,  increasing  from  south  to  north,  in  the 
basin  of  Lake  Champlain;  about  275  feet  at  Ogdensburg,  and  450  feet 
near  the  city  of  Ottawa;  and  300  to  500  feet,  likewise  increasing  northward, 
on  the  country  southwest  of  James  Bay.^  In  Labrador  the  submergence 
was  of  small  amount  at  the  south,  adjacent  to  the  Gulf  of  St.  Lawrence 
and  Newfoimdland;  but  was  about  1,500  feet  at  Nachvak,  near  latitude 
59°  N.,  according  to  Dr.  Robert  Bell;^  and  in  northern  Greenland  and  in 

'  Geol.  Magazine  (3),  Vol.  VI,  1889,  pp.  350-352.  Transactions,  Royal  Society  of  Canada,  Vol.  VIII, 
Sec.  IV,  1890,  pp.  31,  32. 

2A.  S.  Packard,  jr..  Memoirs,  Boston  Soc.  Nat.  Hist.,  Vol.  I,  pp.  231-262.  J.  W.  Dawson,  Notes 
on  the  Postpliocene  Geology  of  Canada;  and  Am.  .lour.  Sci.  (3),  Vol.  XXV,  1883,  pp.  200-202.  C.  H. 
Hitchcock,  Proc,  A.  A.  A.  S.,  Vol.  XXII,  1873,  pp.  169-175;  Geology  of  New  Hampshire,  Vol.  Ill,  pp. 
279-282;  and  Geol.  Magazine  (2),  Vol.  VI,  1879,  pp.  248-250.  G.  H.  Stone,  Am.  Jour.  Sci.  (3),  Vol.  XL, 
pp.  122-144,  Aug.,  1890.  R.  Chalmers,  Transactions  of  the  Royal  Society  of  Canada,  Sec.  IV,  1886,  pp. 
139-145.  Baron  Gerard  de  Geer,  Am.  Geologist,  Vol.  IX,  pp.  247-249,  April,  1892;  and  Proc,  Boston 
Soc.  Nat.  Hist.,  Vol.  XXV,  1892,  pp.  454-477.  Warren  Upham,  Proc,  Boatou  Soc.  Nat.  Hist.,  Vol. 
XXIV,  pp.  127-141,  Dec,  1888;  Am.  Jour.  Sci.,  May,  1889. 

^Bulletin,  G.  S.  A.,  Vol.  I,  1890,  p.  308. 


506  THE  GLACIAL  LAKE  AGASSIZ. 

Grinnell  Land  it  was  from  1,000  to  2,000  feet,  as  shown  by  raised  beach 
deposits  containing  marine  shells.' 

That  the  land  northward  from  Boston  was  so  much  lower  while  the 
ice-sheet  was  being  melted  away  is  proved  by  the  occurrence  of  fossil 
shells  of  far  northern  range,  including  Yoldia  (Lecla)  arctica  Gray,  now 
found  living  only  in  arctic  seas  where  they  receive  muddy  streams  from 
existing  glaciers  and  from  the  Greenland  ice-sheet.  This  species  is  plentiful 
in  the  stratified  clays  resting  on  the  till  in  the  basin  of  James  Bay,  in  the 
St.  Lawrence  Valley,  and  in  New  Brunswick  and  Maine,  extending  south  to 
Portsmouth,  N.  H. 

Scantier  but  yet  conclusive  proofs  of  the  depression  of  British  Colum- 
bia under  the  ice  load  are  found  in  the  valley  of  the  Fraser  River  and  on 
the  Pacific  coast,  in  Vancouver  Island  and  the  Queen  Charlotte  Islands. 
Lamplugh  has  observed  recent  marine  shells  in  a  railway  cutting  on  the 
west  bank  of  the  Harrison  River,  near  its  junction  with  the  Fraser,  at  an 
elevation  not  less  than  100  feet  above  the  sea."  At  New  Westminster,  on 
the  Frazer,  near  its  mouth,  raised  beaches  inclosing  fragments  of  marine 
shells  are  reported  by  Bauerman  about  30  feet  above  the  river.^  Fossilif- 
erovis  mai'ine  deposits  found  in  the  vicinity  of  Victoria  and  Nanaimo,  in  the 
southeast  part  of  Vancouver  Island,  at  small  elevations  above  the  sea,  are 
believed  by  Dr.  G.  M.  Dawson  to  have  been  formed  at  or  near  the  wasting 
edffe  of  the  ice-sheet;*  and  near  the  naiddle  of  the  northeast  side  of  this 
island  two  distinct  deposits  of  till  occur,  with  intervening  beds  of  loess-like 
silts,  from  which  this  author  infers  two  times  of  glaciation,  separated  by  an 
interval  during  which  the  land  was  submerged  from  100  to  200  feet.^ 
Again,  in  the  northeast  part  of  the  Queen  Charlotte  Islands  Dr.  Dawson 

'Quart.  .Jour.  Geol.  Soc,  Vol.  XXXIV,  1878,  pp.  66,  566.  Geol.  Magazine  (3),  Vol.  I,  1884,  p.  522. 
A.  W.  Greely,  Report  on  the  U.  S.  Expedition  to  Latly  Franklin  Bay,  Griunell  Land,  Vol.  II,  1888,  p.  57. 

2Quart.  Jour.  Geol.  Soc.,  Vol.  XLII,  1886,  pp.  284,  285. 

3  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1882-83-84,  p.  33  B. 

<6eoI.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series.  Vol.  II,  for  1886,  p.  99  B ;  Quart. 
Jour.  Geol.  Soc.,  Vol.  XXXIV,  1878,  pp.  97,  98,  and  Vol.  XXXVII,  1881,  p.  279.  Compare  also  Mr.  G.  W. 
Lamplugh's  observations  of  glacial  shell  beds  at  Esquimault,  near  Victoria,  Quart.  Jour.  Geol.  Soc, 
Vol.  XLII,  1886,  pp.  276-284. 

^Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  II,  p.  105  B. 


EEELEVATIOI^  FOLLOWING  THE   ICE  DEPAETUEE.  507 

finds  evidence  of  submergence  to  the  amount  of  200  or  300  feet,  while  the 
glacial  conditions  still  endured.^ 

KEELEVATION    CLOSELY    FOLLOWING    THE    DEPARTURE    OF    THE    ICE-SHEET. 

From  the  Champlain  submergence  this  continent,  since  the  ice  weight 
depressing  it  was  removed,  has  been  uplifted  to  its  present  height.  The 
changes  in  the  levels  of  the  beaches  of  Lake  Agassiz  prove  that  in  the 
interior  of  the  continent  this  movement  closely  followed  the  recession  of 
the  ice;  but  on  the  shores  of  Hudson  Bay  the  reelevation  is  still  in  prog- 
ress, indicating  that  no  long  time  has  passed  since  large  remnants  of  the 
ice  in  that  region  melted  away.  On  the  Atlantic  coast  we  have  different 
evidence  of  the  rise  of  the  land  soon  after  the  ice-sheet  disappeared,  and 
the  movement  there,  as  also  on  the  coast  of  British  Columbia,  resulted  in 
an  elevation  somewhat  higher  than  now,  so  that  the  latest  oscillation  of 
these  regions  has  been  a  subsidence,  which  is  still  very  slowly  continuing. 

The  recent  depression  of  the  eastern  seaboard  is  shown  by  submarine 
stumps  of  trees,  rooted  where  they  grew,  and  by  submerged  peat  bogs, 
which  prove  that  the  whole  coast  from  New  Jersey  to  southern  Greenland 
has  lately  sunk  to  a  moderate  extent.  The  maximum  known  by  these 
observations  is  about  80  feet,  at  which  depth  a  peat  bed  occurs  under  the 
Tantramar  salt  marsh  at  the  head  of  the  Bay  of  Fundy."  After  the  land 
had  recovered  from  the  Champlain  depression  to  its  present  level,  or  per- 
haps to  the  higher  stage  noted,  the  temperature  of  the  North  Atlantic  was 
for  a  time  somewhat  warmer  than  now.  Southern  species  of  marine  mol- 
lusks  were  then  able  to  extend  northward  to  the  Gulf  of  St.  Lawrence; 
but  they  have  since  become  exterminated  by  a  considerable  refrigeration  of 

'Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1878-79,  p.  95  B.  Trans.,  Royal 
Society  of  Canada,  Vol.  Vlll.  Sec.  IV,  1890,  pp.  3-74.  Important  notes  of  recent  changes  in  level  of 
the  coast  of  British  Columbia,  of  the  State  of  Washington,  and  of  southern  Alaska,  are  given  by 
Dr.  Dawson  in  the  Canadian  Naturalist,  new  series.  Vol.  VIII,  pp.  241-248,  April,  1877.  He  concludes 
that  this  area  had  a  preglaoial  elevation  at  least  about  900  feet  above  the  present  sea-level  during 
part  or  the  whole  of  the  Pliocene  period,  this  being  indicated  by  the  fjords;  that  it  was  much 
depressed  during  the  Glacial  period;  and  that  in  Postglacial  time  it  has  been  reelevated  to  a  height 
probably  200  or  300  feet  greater  than  now,  followed  by  subsidence  to  the  present  level,  the  latest  part 
of  this  oscillation  being  a  somewhat  rapid  depression  of  perhaps  10  or  15  feet  during  the  latter  part  of 
the  last  century — a  movement  which  may  still  be  slowly  going  on. 

2  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  new  series,  Vol.  IV,  for  1888-89,  pp.  42  A 
and  10  N. 


508  THE  GLACIAL  LAKE  AGASSIZ. 

the  sea  along  tlie  coast  iinrtli  of  Cape  Cod,  excepting  isolated  colonies.^ 
The  coast  had  been  reelevated  soon  aftei*  the  retreat  of  the  ice-sheet  and 
before  the  southern  mollusks  migrated  northward,  for  in  the  extensive  lists 
of  the  fossil  fauna  of  the  Champlain  beds,  also  denominated  in  their  two 
principal  phases  the  Leda  clays  and  Saxicava  sands,  none  of  the  southern 
species  is  included,  excepting  perhaps  the  oyster  in  southwestern  Maine." 

Postglacial  elevation  of  the  country  along  the  East  Main  coast  of 
Hudson  Bay  and  on  Hudson  Strait  is  shown  by  conspicuous  raised  beaches, 
according  to  Dr.  Robert  Bell,  up  to  heights  of  at  least  300  feet,  while  prob- 
ably others  much  higher  exist  farther  inland.^  In  the  region  draining  from 
the  southwest  to  James  Bay  Dr.  Bell  reports  marine  shells  in  stratified 
beds  overlying  the  glacial  drift  along  the  Moose,  Mattagami,  and  Missinaibi 
rivers  up  to  about  300  feet  above  the  sea;*  along  the  Albany  and  Keno- 
gami  rivers  up  to  a  height  of  about  450  feet;^  and  on  the  Attawapishkat  to 
about  500  feet  above  the  sea."  It  is  also  evident  that  the  shores  of  Hudson 
and  James  bays  are  still  undergoing  elevation,  this  being  proved  by  the 
fresh  appearance  of  the  raised  beaches,  by  driftwood  far  above  the  limit 
of  the  highest  waves  in  storms,  and  by  the  gradual  shoaling  of  harbors. 
The  rate  of  emergence  of  the  eastern  coast  is  estimated  by  Bell  to  be 
between  5  and  10  feet  in  a  century;  Outer  Digges  Island,  at  the  entrance 
of  Hudson  Strait,  has  risen  70  or  80  feet  since  it  was  inhabited  by  Eskimos; 
and  the  rise  of  the  mouths  of  the  Churchill,  Nelson,  and  Hayes  rivers  seems 
to  be  similarly  rapid,  being  estimated  at  about  7  feet  in  a  hundred  years.'' 

In  British  Columbia  the  reelevation  following  the  Champlain  depres- 
sion was  probably  completed  within  a  short  time,  geologically  speaking, 

iProc,  Boston  Soc.  Nat.  Hist.,  Vol.  XXV,  1891-92,  pp.  305-316;  also  Am.  .Tour.  Sci.  (3),  Vol.  XLIII, 
pp.  201-209,  March,  1892. 

2C.  H.  Hitchcock,  "The  geology  of  Portland,"  Proc,  A.  A.  A.  S.,  Vol.  XXII,  for  1873,  pp.  163-175. 
A.  S.  Packard,  Jr.,  "  Observations  on  the  glacial  phenomena  of  Labrador  and  Maine,"  Memoirs  of  the 
Boston  Society  of  Natural  History,  Vol.  1, 1865,  pp.  210-262.  J.  W.  Dawson,  "Notes  on  the  Postpliocene 
geology  of  Canada,"  1872,  pp.  112  (from  the  Canadian  Naturalist,  new  series.  Vol.  A'l). 

=Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1877-78,  p.  32  C ;  for  1882-83-84, 
p.  31  D. 

■"  Ibid.,  Report  of  Progress  for  1875-76,  p.  340 ;  for  1877-78,  p.  7  C. 

5 Ibid.,  Report  of  Progress  for  1871-72,  p.  112;  for  1875-76,  p.  340;  Annual  Report,  new  series.  Vol. 
II,  for  1886,  pp.  34  and  38  G. 

<!  Ibid.,  Annual  Report,  Vol.  II,  p.  27  G. 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1877-78,  pp.  32  C  and  25  CC ;  for 
1878-79,  p.  21  C ;  for  1882-83-84,  pp.  26,  30,  32  DD ;  Annual  Report,  new  series,  Vol.  I,  for  1885,  p.  11  DD. 


OSCILLATIONS  WITH  GLACIATION  IN  OTHEE  COUNTRIES.      509 

after  the  continental  ice-sheet  was  removed,  for  Dawson,  as  before  cited, 
finds  that  this  region  since  then  has  stood  higher  than  now,  allowing  forests 
to  grow  on  shores  which  have  very  recently  become  again  submerged,  as 
on  the  eastern  side  of  the  continent.  During  the  past  hundred  years,  too, 
a  considerable  subsidence  has  taken  place,  according  to  Dall,  at  a  locality 
known  as  Sinking  Point,  in  Chalmers  Bay,  Prince  William  Sound,  on  the 
south  coast  of  Alaska;  but  all  of  that  country  west  of  the  one  hundred  and 
fiftieth  meridian,  to  Bering  Strait  and  the  adjacent  Siberian  coast,  is  stated 
by  this  author  to  be  now  rising  at  a  somewhat  rapid  rate.  Barnacles  are 
found  on  St.  Michael's  Island,  Norton  Sound,  at  least  15  feet  above  high 
tide,  and  driftwood  at  many  localities  on  Norton  Bay  and  Sound  is  "piled 
in  winrows  *  *  *  far  above  the  level  which  the  most  severe  stonns 
and  the  highest  tides  now  attain,  *  *  *  much  decayed,  but  still 
preserving  its  shape."  ^ 

OSCILLATIONS    ASSOCIATED    WITH    GLACIATION    IN    OTHER    COUNTRIES. 

Two  other  areas  of  great  extent,  namely,  Patagonia  and  northwestern 
Europe,  have  been  covered  by  ice-sheets  which  have  disappeared;  and  a 
brief  consideration  of  their  oscillations  attending  the  ice  accumulation  and 
following  its  departure  will  be  useful  in  this  discussion  of  the  causes  of  the 
Pleistocene  earth  movements  of  the  basin  of  Lake  Agassiz  and  of  the  North 
American  glaciated  area. 

The  many  intricate  and  deep  fjords,  chainiels,  and  sounds  on  the  coast 
of  Patagonia,  southern  Chile,  Tierra  del  Fuego,  and  the  Falkland  Islands, 
prove  that  this  part  of  the  earth's  crust  has  lately  stood  for  a  considerable 
time  at  a  much  •  higher  level  than  now.  This  stage  of  elevation  was  fol- 
lowed by  the  envelopment  of  the  southern  extremity  of  the  continent  by 
an  ice-sheet,  which,  according  to  the  observations  of  Darwin  and  Agassiz, 
spread  its  drift  northward  to  latitude  42°,  while  local  glaciers  extended 
farther  north.  When  the  ice  melted  away,  the  land  was  depressed  lower 
than  now,  and  since  then  a  reelevatiou  has  been  in  progress.  Darwin  states 
that  "the  laud  from  the  Rio  Plata  to  Tierra  del  Fuego,  a  distance  of  1,200 
miles,  has  been  raised  in  mass  (and  in  Patagonia  to  a  height  of  between  300 

I  Alaska  and  its  Resources,  1870,  pp.  465, 466. 


510  THE  GLACIAL  LAKE  AGASSIZ. 

and  400  feet)  within  the  period  of  the  now  existing  shells.  The  old  and 
weathered  shells  left  on  the  surface  of  the  upraised  plain  still  partially 
retain  then-  colors."^  Another  evidence  of  the  recency  of  the  uplift  is  sup- 
plied by  the  discovery  by  Agassiz  of  a  saline  lakelet  about  150  feet  above 
the  sea,  in  which  several  species  of  marine  mollusks  were  found  living, 
identical  with  those  of  the  neighboring  seashores.^ 

Northwestern  Europe  also  had  a  much  greater  altitude  during  the 
later  part  of  the  Tertiary  era,  in  which  the  land  suffered  vast  denudation, 
with  erosion  of  fjords  and  channels  that  are  now  submerged  hundreds  and 
even  thousands  of  feet  beneath  the  sea.  About  the  northern  parts  of  the 
British  Isles  the  depths  of  the  submarine  channels  of  the  old  land  sm-face 
are  approximately  from  500  to  800  or  1,000  feet.^*  The  Skager  Rack,  between 
Denmark  and  Norway,  has  a  depth  of  2,580  feet,  with  a  still  deeper  sub- 
mero-ed  valley  running  from  it  west  and  north  to  the  abyssal  Arctic  Ocean.* 
On  the  coast  of  Norway  the  depth  of  Christiania  fjord  below  the  sea-level 
is  1,380  feet;  of  Hardanger  fjord,  2,624  feet;  and  of  Sogne  fjord,  the  longest 
in  Norway,  4,080  feet.^  The  preglacial  altitude  of  these  portions  of  the 
European  glaciated  area  was  therefore  from  1,000  to  4,000  feet  higher  than 
now.  Probably  many,  of  these  submarine  channels  are  more  or  less  filled 
with  the  glacial  drift,  so  that  valleys  originally  descending  continuously 
toward  the  margin  of  the  continental  plateau  have  become  in  some  portions 
changed  to  inclosed  basins.  Another  and  more  probable  explanation  of 
the  much  greater  depth  of  some  of  the  fjords  in  their  inland  portion  than 
at  their  mouths  is  the  depression  of  the  country  while  it  was  ice-covered, 
the  coast  having  subsided  much  less  than  the  interior. 

At  the  close  of  the  Ice  age  in  Europe,  as  in  America,  the  glaciated 
areas  were  mostly  depressed  somewhat  below  their  present  height.  The 
supposed  great  submergence,  however,  up  to  1,200  or  1,500  feet  or  more, 
which  has  been  claimed  by  British  geologists  for  northern  Wales,  north- 
western England,  and  a  part  of  Ireland,  on  the  evidence  of  marine  shells 

'  Voyage  of  the  Beagle,  Chapter  VIII. 

2  Louis  Agassiz :  His  Life  and  Correspondence,  Vol.  II,  p.  716. 

3  James  Geikie,  Quart.  Jour.  Geol.  Soc,  Vol.  XXXIV,  1878,  PI.   XXXIII;   The   Great   Ice  Age, 
2d  ed.,  pp.  279-284,  Pis.  IX-XII. 

■•  Nature,  Vol.  XXIII,  p.  393,  with  map  of  submarine  contour. 

6  T.  F.  Jamieson  in  Geol.  Magazine  (3),  Vol.  VIII,  pp.  387-392,  Sept.,  1891. 


OSCILLATIONS   IN  SCANDINAVIA.  511 

and  fragments  of  shells  in  glacially  transported  deposits,  is  shown  by  Belt, 
Goodchild,  Lewis,  Kendall,  and  others,  to  be  untenable.  Indeed,  these 
fossils,  not  lying  in  the  place  where  they  were  living,  give  no  proof  of  any 
depression  of  the  land,  since  they  have  been  brought  by  currents  of  the  ice- 
sheet  moving  across  the  bed  of  the  Irish  Sea.  But  it  is  clearly  known  by 
other  evidence,  as  raised  beaches  and  fossiliferous  marine  sediments,  that 
large  portions  of  Great  Britain  and  Ireland  were  slightly  depressed  under 
their  burden  of  ice,  and  have  been  since  uplifted  to  a  vertical  extent  rang- 
ing probably  up  to  a  maximum  of  about  300  feet. 

In  Scandinavia  the  valuable  observations  and  studies  of  Baron  Gerard 
de  Geer,  of  the  Geological  Survey  of  Sweden,  have  supplied  lines  of  equal 
depression  of  the  land  at  the  time  of  the  melting  away  of  the  ice.^  This 
region  of  greatest  thickness  of  the  European  ice-sheet  is  found  to  have 
been  depressed  to  an  increasing  extent  from  the  outer  portions  toward  the 
interior.  The  lowest  limit  of  the  submergence,  at  the  southern  extremity 
of  Sweden,  is  no  more  than  70  feet  above  the  present  sea-level,  and  in 
northeastern  Denmark  it  diminishes  to  zero;  but  northward  it  increases  to 
an  observed  amount  of  about  800  feet  on  the  west  shore  of  the  Gulf  of 
Bothnia,  near  latitude  63°.  Along  the  coast  of  Norway  it  ranges  from  200 
feet  to  nearly  600  feet,  excepting  far  northward,  near  the  North  Cape, 
where  it  decreases  to  about  100  feet.  In  proportion  with  this  observed 
range  of  the  subsidence  on  the  coasts  of  Scandinavia,  its  amount  in  the 
center  of  the  country  was  probably  1,000  feet. 

A  very  interesting  history  of  the  postglacial  oscillations  of  southern 
Sweden  has  been  also  ascertained  by  Baron  de  Geer,  which  seems  to  be 
closely  like  the  postglacial  earth  movements  of  the  northeastern  border  of 
North  America.  As  on  our  Atlantic  coast,  the  uplift  from  the  Champlain 
submergence  in  that  part  of  Sweden  raised  the  country  higher  than  now. 
The  extent  of  this  uplift  appears  to  have  been  about  100  feet  on  the  area 
between  Denmark  and  Sweden,  closing  the  entrance  to  the  Baltic  Sea, 
which  became  for  some  time  a  great  fresh-water  lake.  After  this  another 
depression  of  that  region  ensued,  opening  a  deeper  passage  into  the  Baltic 

1  "Quaternary  changes  of  level  in  Scandinavia,"  Bulletin,  6.  S.  A.,  Vol.  Ill,  1892,  pp.  65-68,  with 
map  of  the  late  glacial  marine  area  in  southern  Sweden. 


512  THE  GLACIAL  LAKE  AGASSIZ. 

tlian  uow,  giviug  to  this  brackish  body  of  water  a  considerably  higher 
degree  of  saltness  than  at  present,  with  the  admission  of  several  marine 
mollusks,  notably  Litorina  litorea  Menke,  which  are  found  fossil  in  the  beds 
formed  during  this  second  and  smaller  submergence,  but  are  not  living  in 
the  Baltic  to-day.  Thus  far  the  movements  of  southei'n  Sweden  are  par- 
alleled by  the  postglacial  oscillations  of  New  England  and  eastern  Canada; 
but  a  second  uplifting  of  this  part  of  Sweden  is  now  taking  place,  whereas 
no  corresponding  movement  has  begun  on  our  Atlantic  border.  It  seems 
to  be  suggested,  however,  that  it  may  yet  ensue.  The  subsidence  has 
ceased  or  become  exceedingly  slow  in  eastern  New  England,  while  it  still 
continues  at  a  measm-able  rate  in  New  Jersey,  in  Caj^e  Breton  Island,  and 
in  southern  Greenland. 

So  extensive  agreement  on  opposite  sides  of  the  Atlantic,  and  also  in 
Patagonia,  in  the  oscillations  of  the  land  while  it  was  ice-covered  and  since 
the  departure  of  the  ice-sheets,  has  probably  resulted  from  similar  causes, 
namely,  the  pressure  of  the  ice  weight  and  resilience  of  the  earth's  crust 
when  it  was  unburdened.  The  restoration  of  isostatic  equilibrium  in  both 
North  America  and  Europe  is  attended  by  minor  oscillations,  the  conditions 
requisite  for  repose  being  overpassed  by  the  early  reelevation  of  outer  por- 
tions of  each  of  these  great  glaciated  areas. 

In  view  of  this  harmony  in  the  epeirogenic  movements  of  the  two 
continents  during  the  Glacial  and  Recent  periods,  it  seems  evident  that  the 
close  of  the  Ice  age  was  not  geologically  long  ago,  for  equilibrium  of 
the  disturbed  areas  has  not  yet  been  restored.  Fm-thermore,  the  parallelism 
in  the  stages  of  progress  toward  repose  indicates  nearly  the  same  time  for 
the  end  of  the  Glacial  period  on  both  continents,  and  approximate  syn- 
chronism in  the  pendulum-like  series  of  postglacial  oscillations. 

PLEISTOCENE    OSCILLATIONS    INDEPENDENT    OF    GLACIATION. 

In  this  class  of  changes  are  to  be  included,  wholly  or  in  part,  the  post- 
glacial elevation  of  Grinnell  Land  and  the  northwestern  coast  of  Greenland, 
1,000  to  2,000  feet;^  post-Pliocene  upward  movements  of  2,000  feet  or 

■  Quart.  Jour.  Geol.  Soc,  Vol.  XXXIV,  1878,  pp.  66  and  566.     Geol.  Mag.  (3),  Vol.  I,  1884,  p.  522. 
A.  W.  Greely,  Report  of  the  U.  S.  Expedition  to  Lady  Franklin  Bay,  Grinnell  Land,  Vol.  II,  1888,  p.  57. 


OSCILLATION  INDEPENDENT  OF   GLACIATION.  513 

more  in  Jamaica  and  Cuba/  and  of  about  1,100  feet  in  Barbados;^  the 
recent  ujjlift  of  the  coast  of  Peru  at  least  2,900  feet,'  which  in  diminished 
amount  seems  to  extend  along  the  whole  range  of  the  Andes ;  *  its  probable 
connection  with  the  upheaval  of  the  Cordilleras  of  North  America,  where 
Le  Conte^  and  Diller'*  believe  that  the  elevatory  movements  reached  their 
greatest  intensity  in  early  Quaternary  time,  causing  a  rise  of  several 
thousands  of  feet  in  the  Sierra  Nevada;  and  the  apparently  correlative 
subsidence  of  a  great  area  dotted  with  coral  islands  in  the  Pacific.  The 
Pleistocene  iiplifts  of  the  Andes  and  Rocky  Mountains  and  of  the  West 
Indies  make  it  nearly  certain  that  the  Isthmus  of  Panama  has  been  simi- 
larly elevated  during  this  period.  On  the  line  of  the  Panama  Railway  the- 
highest  land  rises  only  299  feet  above  the  sea,  and  the  highest  on  the  pro- 
posed route  of  the  Nicaragua  Canal  is  about  133  feet;  while  the  Isthmvis 
nowhere  attains  the  height  of  1,000  feet.^  It  may  be  true,  therefore, 
that  submergence  of  this  istlnnus  was  one  of  the  causes  of  the  Glacial 
period,  the  continuance  of  the  equatorial  oceanic  current  westward  into  the 
Pacific  having  greatly  diminished  the  Gulf  Stream,  which  carries  warmth 
from  the  tropics  to  the  northern  Atlantic  and  northwestern  Europe. 

Pleistocene  mountain-building  is  kiiown  to  have  occurred  on  a  most 
massive  scale  in  Asia,  where  the  Himalayas,  stretching  1,500  miles  from 
east  to  west,  and  towering  20,000  to  29,000  feet  above  the  sea,  are  known 
to  have  been  formed  in  great  part  during  this  latest  geologic  period,^  con- 

'  J.  6.  Sawkins,  Keports  on  the  Geology  of  Jamaica,  1869,  pp.  22,  23,  307,  311,  324-329 ;  W.  0.  Crosby, 
"On  the  mountains  of  eastern  Cuba,"  Appalachia,  Vol.  Ill,  pp.  129-142.  Compare  William  M.  Gabb's 
memoir,  "On  the  topography  and  geology  of  Santo  Domingo,"  Trans.,  Am.  Phil.  Soc,  Vol.  XV,  pp. 
103-111. 

2  "The  geology  of  Barbados,"  by  A.  .1.  Jukes-Browne  and  J.  B.  Harrison,  Quart.  Jour.  Geol.  Soc, 
Vol.  XLVII,  pp.  197-250,  Feb.,  1891. 

^  A.  Agassiz,  Proc.,  Am.  Acad,  of  Arts  and  Sciences,  Vol.  XI,  1876,  p.  287 ;  and  Bulletin  of  the  Museum 
of  Comparative  Zoology  at  Harvard  College,  Vol.  Ill,  pp.  287-290.  Above  this  height,  at  which  corals 
are  found  attached  to  rocks,  recent  elevation  of  much  greater  amount  seems  to  be  indicated  by 
terraces,  by  saline  deposits,  and  by  the  presence  of  eight  species  of  AUorcheates,  a  marine  genus  of 
Crustacea,  in  Lake  Titicaca,  12,500  feet  above  the  sea. 

■*  Darwin's  Voyage  of  the  Beagle,  Cha^jter  XVI. 

<>  Am.  Jour.  Sci.  (3),  Vol.  XXXII,  pp.  167-181,  Sept.,  1886 ;  Vol.  XXXVIII,  pp.  257-263,  Oct.,  1889. 

<^  U.  S.  Geol.  Survey,  Eighth  Annual  Report,  for  1886-87,  pp,  428-432. 

'  Charles  Eieketts,  "The  cause  of  the  Glacial  period,  with  reference  to  the  British  Isles,"  Geol. 
Magazine  (2),  Vol.  II,  1875,  pp.  573-580.  A.  R.  Wallace,  The  Geographical  Distribution  of  Animals,  Vol. 
I,  p.  40. 

"Manual  of  the  Geology  of  India,  by  H.  B.  Medlicott  and  W.  T.  Blanford;  Calcutta,  1879;  Part 
I,  pp.  Ivi,  372;  Part  II,  ijp.  569-571,  667-669,  672-681. 
HON  XXV 33 


514  THE  GLACIAL  LAKE  AGASSIZ. 

temporaueously  with  the  glaciation  of  North  America,  Europe,  and  portions 
of  the  southern  hemisphere.  Within  the  same  time  the  great  table-land  of 
TMbet^  and  much  of  central  and  northwestern  Asia  have  been  uplifted;  the 
tract  extending  from  the  Black  and  Caspian  seas  northeast  to  the  Arctic 
Ocean  has  risen  to  form  a  land  surface ;  and  the  deep  basin  of  Lake  Baikal 
probably  has  been  formed  in  connection  with  these  crustal  movements. 
Accompanying  the  formation  of  the  Himalayas,  there  has  been  doubtless 
much  disturbance  by  faults,  local  uplifts,  and  here  and  there  plication  of 
strata  along  the  whole  complex  east  to  northwest  and  west  mountain  sys- 
tem of  Oceanica,  Asia,  Europe,  and  northern  Africa,  from  New  Guinea,  the 
Suuda  Islands,  Anam,  and  Siam,  to  the  Caucasus,  Carpathians,  Balkans, 
Apennines,  Alps,  Pyrenees,  and  Atlas  mountains,  stretching  quite  across 
the  Eastern  Hemisphere ;  but  the  greater  part  of  the  relief  from  the  previ- 
ously existing  deformation  of  the  earth  was  doubtless  along  the  central  part 
of  the  belt,  in  the  colossal  Himalayan  range.  In  like  manner  the  North 
American  Cordilleras  and  the  Andes,  reaching  in  one  continuous  moun- 
tain system  from  the  Arctic  Circle  to  Cape  Horn,  have  experienced  within 
the  same  period  great  disturbances,  as  already  noted,  similar  to  those  of  the 
mountains  of  southern  Europe  and  the  adjacent  part  of  Africa.  With  this 
American  orographic  belt  is  also  probably  to  be  associated  the  mountain 
system,  consisting  largely  of  volcanoes  now  active,  which  forms  the  Aleutian 
Islands,  Kamchatka,  the  Kurile  Islands,  Japan,  Formosa,  the  Philippines, 
Borneo,  and  Celebes,  lying  nearly  in  the  same  great  circle  with  the  Andes 
and  Rocky  mountains,  and  with  them  continuous  in  an  arc  of  about  240°. 
Along  two  lines  transverse  to  each  other,  one  having  an  extent  of  half  and 
the  other  of  two-thirds  of  the  earth's  circumference,  the  great  lateral  pres- 
sures of  the  earth's  crust  which  probably  caused  the  elevation  and  glaciation 
of  extensive  areas  during  the  Pleistocene  period  have  been  relieved  by 
plication,  faults,  and  uplifts  in  the  processes  of  the  formation  of  mountain 
ranges. 

Asia  had  no  extensive  ice-sheet  like  those  of  Europe  and  North  Amer- 
ica, probably  because  a  sufficient  elevation  was  not  attained  there  until  the 
Himalayas  and  Thibet  were  uplifted  in  the  Glacial  period.     The  southern 

■Ibid.,  Part  II,  pp.  585,  586,  669-672. 


CHANGES   OF  THE   SEA  DUE   TO   ICE   ACCUMULATION,        515 

latitude  of  the  Himalayan  rauge  aud  the  position  of  Thibet  and  Mongolia 
in  an  arid  and  partly  rainless  belt,  which  stretches  thence  west  to  the 
Sahara,  forbade  their  glaciation;  but  from  these  recently  uplifted  Asiatic 
table-lands  and  mountains  the  most  extensive  Pleistocene  stratified  deposits 
in  the  world  have  been  brought  down  by  rivers  and  spread  in  the  vast  low 
plains  of  Siberia,  eastern  China,  and  northern  India,  sloping  gently  toward 
the  sea,  into  which  the  finer  part  of  this  alluvium  is  carried.  All  the  puz- 
zling features  of  the  Chinese  loess  formation,^  reaching  to  great  elevations 
with  such  thickness  aud  slopes  of  its  surface  that  it  could  not  be  so  accumu- 
lated as  alluvium  of  flooded  streams  under  the  present  conditions,  seem  to 
be  readily  explained  by  referring  its  deposition  to  annual  floods  from 
immense  snow  melting  dm'ing  the  European  and  North  American  Glacial 
period  upon  the  gradually  rising  central  part  of  the  Asiatic  continent, 
which  consists  largely  of  easily  erosible  strata,  and  had  in  pre-Glacial  time 
become  extensively  disintegrated  by  weathering  under  a  dry  climate. 

EFFECTS    OF    ICE    ACCUMULATION    ON   THE    SEA-LEVEL. 

During  the  Grlacial  period  significant  changes  of  the  sea-level  were 
caused,  first,  by  abstraction  of  water  from  the  ocean  and  its  deposition  on 
the  land  as  snow,  which  under  pressure  made  the  vast  ice-sheets;  and, 
second,  by  ice  attraction  of  the  ocean,  lowering  it  still  further,  except  in  the 
vicinity  of  glaciated  lands.  An  area  of  about  4,000,000  square  miles  in 
North  America  and  another  of  about  2,000,000  square  miles  in  Europe 
were  covered  by  ice-sheets,  which  in  their  maximum  extent  had  2jrobably 
an  average  thickness  of  a  half  or  two-thirds  of  a  mile,  or  perhaps  even  of  1 
mile.  Disregarding  the  accumulation  of  ice-sheets  of  smaller  extent,  which 
probably  or  possibly  existed  at  the  same  time  in  parts  of  Asia  and  of  the 
southern  hemisphere,  as  also  the  glaciers  of  mountain  districts,  the  lowering 
of  the  ocean  surface,  which  covers  approximately  145,000,000  square  miles, 
would  slightly  exceed  100  feet,  if  the  mean  depth  of  the  ice  accumulation 
was  a  half  mile.     More  probably  the  sea  over  the  whole  globe  was  thus 

'Baron  RichthofenjGeol.  Magazine  (2),  Vol.  IX,  1882,  pp.  293-305.  J.  D.  Whitney,  Am.  Naturalist, 
Vol.  XI,  pp.  705-713,  Dec,  1877.  R.  Pumpelly,  Am.  Jour.  Scl.  (3),  Vol.  XVII,  pp.  133-144,  Feb.,  1879. 
E.  W.  Hilgard,  Am.  Jour.  Sci.  (3),  Vol.  XVIII,  pp.  106-112,  Aug.,  1879. 


516  THE  GLACIAL  LAKE  AGASSIZ. 

dejiressed  fully  150  feet,  which  would  correspond  to  an  average  of  about 
3,600  feet  of  ice  ou  the  glaciated  areas  of  North  America  and  Europe. 

For  the  second  factor  in  causing  such  changes,  Mr.  Woodward's  compu- 
tations before  cited  indicate  that  gravitation  toward  the  ice  would  further 
depress  the  ocean  probably  25  to  75  feet  within  the  tropics  and  in  the 
southern  hemispliere,  while  it  would  raise  the  level  enough  near  the  borders 
of  the  ice-sheets  to  counterbalance  approximately  the  depression  due  to  the 
diminution  of  the  ocean's  volume,  and  would  lift  portions  of  the  North 
Atlantic  and  of  the  Arctic  Sea  })erlia])s  200  or  300  feet  higher  than  now. 
Stream  erosion  while  the  sea  was  lowered  to  supply  the  ice  of  the  Glacial 
period  may  explain  the  indentations  of  the  southeastern  coast  of  the  United 
States,  as  Pamlico  and  Albemarle  sounds,  besides  similar  inlets  in  many 
other  parts  of  the  world;  but  the  excavation  of  Chesapeake  and  Delaware 
bays  seems  more  proljably  referable,  at  least  in  part,  to  the  time  of  pre- 
glacial  elevation,  with  the  channeling  of  the  now  submerged  Hudson  fjord. 

PKOBABLE  RELATIONSHIP  OF  EPEIKOGENIC  MOVEMENTS  THROUGH- 
OUT THE  AVORLD  TO   GLACIATION. 

In  view  of  the  extensive  Pleistocene  oscillations  of  land  and  sea  both 
in  glaciated  and  unglaciated  regions,  it  seems  a  reasonable  conclusion  that, 
while  some  of  these  movements,  as  those  affecting  the  beaches  of  Lake 
Agassiz,  have  resulted  directly  from  the  accumulation  and  dissolution  of 
ice-sheets,  more  generally,  when  the  wliole  area  of  the  earth  is  considered, 
they  have  been  independent  of  glaciation.  May  not  such  movements  of 
the  earth's  crust,  then,  have  elevated  large  portions  of  continents,  as  the 
northern  half  of  North  America  and  the  northwestern  part  of  Europe,  either 
together  or  in  alternation,  to  heights  like  those  of  the  present  snow-lines  on 
mountain  ranges,  until  these  plateaus  became  deeply  channeled  by  fjords 
and  afterward  covered  by  ice-sheets"?  For  the  recentness  of  the  Ice  age, 
believed  to  have  ended  in  the  region  of  Lake  Agassiz  and  the  Laurentian 
lakes  not  more  than  10,000  to  6,000  years  ago,^  forbids  our  referring  the 
glacial  climate  to  conditions  lirought  aboiit  by  a  period  of  increased  eccen- 
tricity of  the  earth's  orbit  from  240,000  to  80,000  years  ago,  which  has  been 

>  See  Chapter  V,  pp.  238-240. 


CAUSE    OF   THE    ICE    AGE.  517 

SO  fibly  maintained  by  CroU  and  (leikie;  and  some  otlier  adeqnate  canse 
or  causes  must  be  sought  for  the  glaciation  of  these  great  continental  areas 
and  otlier  districts  of  smaller  extent,  botli  in  tlie  northern  and  southern 
hemispheres,  during-  the  Pleistocene  period. 

The  principal  cause  of  the  Ice  age  seems  to  the  writer  to  be  probably 
found  b}^  the  clew  supplied  in  the  relations  already  stated  of  the  earth's 
crust  and  interior  whereby  they  become  somewhat  distorted  from  the 
splieroidal  form  while  the  process  of  contraction  goes  forward,  the  lateral 
pressure  bearing  down  some  portions  of  the  earth's  surface  and  uplifting 
other  extensive  areas.  The  protuberant  plateaias,  swept  o^'er  by  moisture- 
laden  winds,  would  be  the  gatliering  grounds  of  vast  ice-sheets.  A  similar 
explanation  of  the  Glacial  period  was  long  ago  proposed  by  Lyell  and 
Dana,  but  without  referring  the  elevatory  movements  to  the  earth's  defor- 
mation by  contraction  and  accumulating  lateral  pressure  \\'hile  approaching 
an  epoch  of  mountain-building,  which  fundamental  principle  was  first  sug- 
gested to  me  in  an  article  from  the  pen  of  Prof.  W.  0.  Crosby  on  the  origin 
and  relations  of  continents  and  ocean  basins.' 

During  the  periods  immediately  preceding  great  plications  and  short- 
ening of  segments  of  the  earth's  crust  involved  in  the  formation  of  lofty 
mountain  ranges,  the  broad  crustal  movements  causing  glaciation  would  be 
most  widespread  and  attain  their  maximum  vertical  extent.  The  accumu- 
lation of  ice-sheets  may  have  brought  about  the  depression  of  their  areas, 
witli  corresponding  elevation  of  other  plateaus,  which  in  turn  would  become 
ice-covered,  so  that  the  epochs  of  glaciation  of  the  Northern  and  Southern 
hemispheres,  or  of  North  America  and  Europe,  may  have  alternated  with 
each  otlier.^  More  probably,  however,  as  shown  by  the  observations  and 
studies  of  Salisbury,  Geikie,  Chamberlin,  the  present  writer,  and  others, 
the  glaciations  of  North  America  and  Europe  were  approximately  synchro- 
nous ;  and  even  the  successive  stages  of  the  Ice  age  on  these  two  continents 


'Proc,  BostoQ  Soc.  Nat.  Hist.,  1883,  Vol.  XXII,  pp.  455-400. 

^Compare  the  opinions  of  Capt.  F.  W.  Hiittori,  cited  in  A.  Gcikio's  Text-book  of  Geology,  2d  ed., 
p.  912,  that  the  former  gre.iter  extension  of  glaciers  in  New  Zealand  was  cansed  by  an  increase  in  the 
elevation  of  the  land,  and  that  it  belonged  to  a  much  earlier  time  than  the  Ice  age  in  the  northern 
hemisphere,  probably  to  the  Pliocene  period. 


518  THE  GLACIAL  LAKE  AGASSIZ. 

have  a  remarkable  parallelism,  which  probably  indicates  a  similar  sequence 
of  events  on  the  opposite  sides  of  the  North  Atlantic.^ 

"Wlien  the  building  up  of  a  great  range  of  mountains  ensued,  which 
may  have  been  initiated  and  accelerated  by  the  repeated  depressions  under 
ice  weight  and  consequent  transfers  of  the  earth's  deformation  from  one 
region  to  another,  the  accumulated  stress  in  the  earth's  crust  with  develop- 
ment of  immense  lateral  pressvire  would  be  diminished  below  the  limit  of 
its  competency  to  cause  glaciation. 

It  seems  probal)le  that  the  rate  of  the  earth's  contraction  has  been 
somewhat  uniform  throughout  the  vast  ages  known  to  us  by  the  researches 
of  geology ;  but  the  corrugation  of  the  earth's  surface  in  mountain-building 
has  been  much  more  rapid  in  some  epochs  than  in  others,  and  between  the 
times  of  formation  of  great  mountain  ranges  there  have  been  long  intervals 
of  quietude.'  The  slowly  progressing  contraction  of  the  globe  has  been 
uninterrupted,  and  in  some  way  the  cooled  outer  part  of  the  crust  which 
has  not  shared  in  this  diminution  of  volume  has  been  able  to  accommodate 
itself  to  the  slninking  inner  mass.  As  stated  in  previous  pages,  this  has 
probably  resulted  in  distortion  of  the  earth's  form,  both  of  the  whole  thick- 
ness of  the  crust  and  of  the  plastic  or  molten  interior,  within  moderate 
limits,  during  the  periods  of  quiet,  until  so  much  lateral  pressure  has  been 
accumulated  as  to  compress,  fold,  and  uplift  the  strata  of  a  mountain  range. 

In  attributing  the  severe  climate  of  the  Glacial  period  to  great  uplifts  of 
the  areas  glaciated  through  such  deformation  preparatory  to  the  process 
of  mountain-building,  it  is  distinctly  implied  that  Pleistocene  time  has  been 
at  first  exceptionally  marked  by  such  broad  crustal  movements  and  has 
since  gained  comparative  rest  from  the  lateral  stress  to  which  they  were 
due  by  equally  exceptional  plication,  uplifts,  and  faults,  in  the  birth  and 
growth  of  mountains.  Further,  it  is  implied  also  that  stress  in  the  earth's 
crust  had  been  gradually  increasing  through  long  previous  time,  while  the 
processes  of  mountain-building  failed  to  keep  pace  with  contraction,  but 

'E.  D.  Salisbury,  Am.  .Jour.  Sci.  (3),  Vol.  XXXV,  pp.  401-407,  May,  1888.  James  Geikie  and  T.  C. 
Chamberlin,  The  Great  Ice  Age,  third  ed.,  1894 ;  Journal  of  Geology,  Vol.  Ill,  pp.  241-277,  April-May, 
1895.  Warren  Upham,  Am.  Naturalist,  Vol.  XXIX,  pp.  235-241,  March,  1895;  Am.  Geologist,  Vol.  XV, 
pp.273-295.  May,  1895. 

''Dana's  Mauual  of  Geology,  3d  ed.,  p.  795.    Prestwich's  Geology,  Vol.  I,  Chapter  XVII. 


CAUSE   OF  THE  ICE  AGE.  519 

were  still  sufficient  to  keep  the  earth's  deformation  less  than  is  required  to 
produce  glaciation;  for  no  evidences  of  intense  and  widely  extended  glacial 
conditions  are  found  in  the  great  series  of  Tertiary  and  Mesozoic  forma- 
tions, representing  the  earth's  history  thi-ough  probably  ten  to  fifteen  million 
years.  And,  indeed,  these  conclusions,  drawn  from  the  Pleistocene  period 
and  the  absence  of  glaciation  through  vast  eras  preceding,  accord  well  with 
the  known  age  and  stages  of  growth  of  mountain  ranges  that  have  been 
formed  during  these  eras.  No  period  since  the  close  of  Paleozoic  time  has 
been  more  characterized  by  mountain-building  than  the  comparatively  short 
Pleistocene,  whose  duration  may  probably  be  included  within  100,000  or 
150,000  years. 

Elevation  of  broad  areas,  as  half  of  North  America  and  half  of  Europe, 
either  synchronously  or,  less  probably  for  these  companion  continental 
regions  adjoining  the  North  Atlantic,  in  alternation,  to  such  heights  that 
their  precipitation  of  moisture  throughout  the  year  was  nearly  all  snow, 
gradually  forming  ice-sheets  of  great  thickness,  seems  consistent  with 
the  conditions  of  the  earth's  crust  and  interior  which  are  indicated  by  the 
changes  in  the  levels  of  the  beaches  of  Lake  Agassiz.  A  plastic  interior 
or  molten  magma  beneath  the  solid  crust  accounts  for  the  uplift  of  the  area 
of  this  glacial  lake,  with  its  gradual  increase  from  south  to  north,  and  also 
appears,  in  connection  with  contraction  of  the  earth  and  the  formation  of 
moxintain  ranges,  to  afford  an  adequate  explanation  of  glaciation.  It  is 
probable  that  the  great  uplifts  which  are  thus  supposed  to  have  caused  ice 
accumulation  were  very  slow  in  their  progress,  and  that  their  effect  upon 
extensive  continental  areas  was  so  distributed  that  the  maximum  changes 
in  slope  on  their  borders  would  nowhere  exceed  20  or  30  feet  or  at  the 
most  50  or  75  feet  per  mile,  while  perhaps  some  portions  of  the  uplifted 
region  would  receive  no  change  of  slope.  And  the  subsidence  beneath  the 
weight  of  accumulated  ice  was  probably  slow,  though  apparently  much 
faster  than  the  processes  of  preglacial  and  interglacial  elevation,  and  was 
similarly  distributed,  no  limited  district  being  greatly  changed.  Excepting 
the  areas  where  disturbances  of  mountain-building  or  extraordinary  rising 
or  sinking  of  mountain  ranges  were  associated  with  these  movements,  the 
contour  of  the  country,  with  its  valleys,  hills,  and  mountains,  remained  in 


520  THE  GLACIAL  LAKE  AGASSIZ. 

general  the  same  from  preglacial  time,  through  the  Ice  age,  to  the  present, 
with  only  changes  of  slope,  commonly  small  in  any  limited  tract,  which,  in 
long  distances,  allowed  great  upheavals  and  depressions.  The  elevation  of 
the  central  part  of  glaciated  areas,  with  downward  slopes  on  all  sides, 
favored  the  outward  flow  of  the  ice-sheets  and  their  erosion  and  transpor- 
tation of  the  drift.  But  mountains  and  hills  jutted  upward  in  ridges  and 
peaks  within  the  moving  ice-sheets,  as  they  now  stand  forth  in  bold  relief 
above  the  lowlands;  and  the  ice,  with  its  inclosed  di'ift,  was  pushed  around 
and  over  them,  some  portions  being  deflected  on  either  side,  and  usually  a 
larger  part  being  earned  upward  across  their  tops. 

EPEIR06ENIC   MOVEMENTS   INDEPENDENT  OF   GLACIATION  OFTEN  COMBINED  V/ITH 
OTHERS    DUE    TO    THE    ICE    WEIGHT    AND    TO    ITS    REMOVAL. 

The  foregoing  review  of  the  Pleistocene  epeirogenic  movements  of 
various  parts  of  the  world  shows  that  many  of  them  have  affected  coun- 
tries Avhich  never  were  glaciated.  In  these  areas  the}^  have  been  mostly 
or  wholly  without  any  demonstrable  relationship  to  glaciation.  Again,  in 
counti'ies  which  have  become  ice-covered,  we  learn  from  fjords  and  sub- 
merged river  valleys  that  great  epeirogenic  elevation  of  the  land  preceded 
the  accumulation  of  the  ice-sheets.  These  movements  also  were  evidently 
independent  of  glaciation,  not  being  caused  by  it,  though,  on  the  other 
hand,  the  writer  lielieves  that  they  were  the  cause  of  the  ice  accumulation 
and  of  its  resulting  drift  deposits.  The  more  extended  epeirogenic  move- 
ments of  the  earth  within  the  Pleistocene  period  have  probably  arisen  from 
the  relationship  of  the  earth's  crust  and  interior,  and  in  areas  of  suffi- 
ciently high  latitudes,  and  in  mountain  districts,  they  have  here  and  there 
produced  epochs  of  glaciation. 

While  so  widespread  earth  movements  not  due  to  glaciation  have  been 
taking  place  throughout  this  period,  it  is  evident  that  some  of  them  would 
probably  be  in  progress  in  glaciated  countries  at  the  same  time  with  the  ice 
accumulation  and  after  the  departm'e  of  the  ice-sheets,  being  combined  in 
their  effects  with  other  crustal  movements  due  to  the  weighting  of  the  crust 
by  the  ice-load,  and  to  its  relief  by  the  ice-melting.  Thus,  for  example, 
while  we  may  refer  the  rise  of  the  greater  part  of  North  America  from  the 


UPLIFT  HEBE  DUE  TO  DEPARTURE  OF  THE   ICE.  521 

Late  Glacial  or  Champlaiu  subsidence  to  the  resilience  of  the  earth's  crust 
on  account  of  the  departure  of  the  ice,  the  uplifting  of  northern  Labrador 
and  of  northern  Greenland  and  Grinnell  Land  has  been  too  great  in  verti- 
cal extent  to  be  proportionate  with  the  probable  thickness  of  the  ice-sheet 
on  those  areas.  Their  uplifting  has  been  in  its  greater  part  probably  due 
to  a  movement  independent  of  glaciation. 

Epeirogenic  movements  of  regions  which  have  not  been  ice-covered 
seem  in  some  instances  referable  to  a  transfer  of  disturbances  from  glaciated 
districts.  Accompanying  the  subsidence  of  ice-loaded  tracts,  there  were 
doubtless  uplifts  of  contiguous  regions,  perhaps  sometimes  including  outer 
portions  of  the  country  glaciated.  For  example,  the  upheaval  of  the  St. 
Elias  range  and  of  its  foothills,  found  by  Russell  to  have  taken  place  sub- 
sequent to  a  long  and  severe  glaciation  of  that  region,^  may  very  probably 
have  been  correlative  with  the  Champlain  subsidence  ending  the  Glacial 
period  in  the  northern  United  States. 

UPLIFT  OF  THE  BASI3^^  OF  LAKE  AGASSIZ  APPARENTLY  ATTRIBUTA- 
BLE WHOLLY  TO  THE  DEPARTURE   OF  THE  ICE-SHEET. 

Within  the  basin  of  the  glacial  Lake  Agassiz  I  believe  that  high  pre- 
glacial  altitude,  affecting  likewise  all  the  North  American  glaciated  area, 
was  terminated  by  tlie  depression  of  the  land  while  it  was  ice-burdened. 
All  the  movements  which  this  basin  has  since  experienced,  as  recorded  by 
the  changes  of  levels  of  the  beaches,  seem  to  have  resulted  from  the  tend- 
ency of  the  earth's  crust  to  regain  equilibrium,  after  the  ice  melted  away, 
by  a  moderate  uplift,  with  inflow  of  the  plastic  or  molten  magma  beneath. 
The  very  regular  gradation  in  the  differential  uplifting  of  tlie  old  shore- 
lines, and  its  progress  almost  to  completion  while  this  lake  was  still  held  by 
an  ice  barrier,  accord  well  witli  this  explanation.  No  element  of  epeiro- 
genic disturbance  is  known  here  which  is  not  readily  accounted  for  by  this 
hypothesis.  The  explanation  is  found  to  be  adequate  and  applicable  to  all 
the  features  of  the  progressive  changes  in  the  levels  of  the  beaches.  The 
very  small  component  which  could  be  ascribed  to  postglacial  change  in  the 

'  "Mount  St.  Elias  and  its  glaciers,"  Am.  Jour.  Sci.  (3),  Vol.  XLIII,  pp.  1G9-182,  with  map,  March, 
1892.  - 


522  THE  GLACIAL  LAKE  AGASSIZ. 

temperature  of  this  part  of  the  earth's  crust  on  account  of  the  departure  of 
the  ice  would  be  practically  insignificant  in  comparison  with  the  direct 
effects  of  the  removal  of  the  ice  weight;  and  its  small  proportion  in  the 
whole  result  would  be  to  diminish  instead  of  to  increase  its  amount.  Upon 
this  district,  therefore,  it  seems  well-nigh  certain  that  no  other  important 
movement  of  elevation  or  of  depression  has  taken  place  in  connection  with 
that  dependent  on  relief  from  the  previously  existing  ice  load. 

But  a  fraction  of  the  changes  in  the  levels  of  this  basin  was  due  to 
the  diminution  and  final  cessation  of  the  ice  attraction  in  its  effect  to  draw 
water  surfaces  and  the  geoid  level  upward  in  the  direction  of  the  ice  mass. 
The  proportion  of  this  element  may  apparently  have  been  as  large  as  a 
sixth  or  a  quarter  of  the  measured  changes  of  levels;  but  its  supposed 
amount,  so  far  as  I  am  able  to  indicate  it,  is  derived  from  estimates  of  the 
volume  of  the  ice-sheet,  rather  than  from  a  discrimination  of  this  part  from 
that  due  to  elevation  of  the  land.  The  two  agencies  of  change  were  nearly 
synchronous  in  their  action  upon  the  levels  of  the  old  shores,  their  eflPects 
were  distributed  in  the  same  manner  in  their  relationship  to  time  and  space, 
and  both  had  almost  ceased  within  this  basin  when  the  ice  barrier  of  the 
glacial  lake  was  melted  away. 

After  progressively  uplifting  the  area  of  Lake  Agassiz,  first  chiefly  in 
its  southern  half  and  afterward  mostly  at  the  north,  but  nearly  ending  their 
work  here  while  the  glacial  lake  yet  existed,  these  agencies  have  since  been 
elevating  the  basin  of  Hudson  and  James  bays.  The  latter  part  of  their 
labor  remains  unfinished,  but  during  each  century  approaches  considerably 
toward  its  completion,  which  will  fully  restore  equilibrium  or  isostasy  to 
this  portion  of  the  earth's  crust. 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.  XXXVI 


s  eiEN  a  CO  ' 


NL\P  SHO>VlNG  'nil-:  OISTHIBin'IOX  .\ND  !)I':i>TUS  OK  .MH'KSIAN  Wi:iJ.S  IN  Till':  UKU  UlSV.n  VAIJ.l-:^'. 

Scak-,  about  VJ  niUes  to  nii  incli. 

Artesian  Veils  wholiv  u\  \\u-  \^v\U       "'.*\\  Ailnsiaii  W.-lls  and  otlicr  Horiii£s  rp<-H'hiuo  lo  U\c  IV-d  |{orks    iV*oi 

/j(^//ffLS  r'ljf  nt}ff(J  ill  ti-ft  bt^lnw  fju-  .snrthcc.  tor  flicir  n:J<ifjnii.\Jn/>  in  tJif  st-a  Jcx-fi,  sff*  Plfiio  X . 


CHAPTER  X. 

ARTESIAN   AND   COMMON   WELLS   OF  THE   RED   RIVER 

VALLEY. 

On  the  broad,  fertile  plain  called  the  Red  River  Valley,  which  was  the 
central  and  deepest  portion  of  the  bed  of  the  glacial  Lake  Agassiz,  many 
artesian  wells  have  been  obtained  within  the  thick  drift  sheet,  deriving  their 
supply  of  water  from  porous  beds  or  veins  of  sand  and  gravel  beneath,  and 
frequently  between,  deposits  of  bowlder-clay  or  till.  The  depths  of  these 
wells  vary  from  40  feet,  or  rai'ely  less,  to  about  250  feet,  or  rarely  300  feet, 
while  a  few  others  penetrate  deeper,  passing  into  the  underlying  Cretaceous 
beds,  or  northward  into  Silurian  strata.  The  height  to  which  the  water  is 
capable  of  rising  above  the  surface  of  the  ground  is  often  only  a  few  feet 
and  seldom  more  than  25  to  50  feet.  Hundreds  of  these  flowing  wells, 
commonly  1  to  2  inches  in  diameter  of  pipe,  are  in  use  on  farms,  at  grain 
elevators,  and  for  the  supply  of  towns,  on  both  the  Minnesota  and  North 
Dakota  sides  of  the  Red  River.  Their  distribution  and  range  of  depth, 
both  in  the  United  States  and  in  Manitoba,  are  shown  in  PI.  XXXVII. 
Some  tracts  of  considerable  area  within  this  valley,  however,  fail  to  find 
artesian  water,  but  even  these  generally  encounter  water-bearing  layers  at 
depths  corresponding  with  those  of  the  artesian  wells,  from  which  water 
rises  nearly  to  the  surface. 

Common  wells  throughout  the  whole  area  of  Lake  Agassiz  and  upon 
the  adjoining  country  usually  obtain  a  supply  of  water  sufficient  for  ordi- 
nary farm  and  domestic  uses  within  depths  ranging  from  10  feet  to  50  feet 
or  occasionally  more.  But  the  quality  of  their  water,  as  also  of  the 
artesian  wells,  is  often  disagreeable.  The  fame  of  the  Red  River  Valley 
for  its  large  harvests  of  "No.  1  hard"  wheat,  averaging  20  bushels  to  the 
acre,  is  nearly  equaled  by  the  unenviable  reputation  of  the  water  sup- 
plied by  its  wells.  The  drift  here  contains  much  of  the  carbonates  and 
sulphates  of  lime  and  magnesia,  derived  from  the  Cretaceous  strata  which 

523 


524  THE  GLACIAL  LAKE  AGASSIZ. 

covered  this  area  and  were  plowed  up  by  the  ice-sheet,  mixed  with  much 
di'ift  from  the  region  of  granites,  gneiss,  and  crystalHne  schists  on  the 
northeast,  and  redeposited  as  till.  The  soluble  alkaline  ingredients  of 
the  soil  impregnate  all  the  waters  of  wells,  springs,  and  streams  in  this 
region ;  and  in  the  dry  season  they  are  often  seen  forming  a  white  or  gray 
efflorescence  on  the  surface  of  the  land,  resembling  frost,  sometimes  a 
quarter  of  an  inch  thick,  being  the  residue  from  the  evaporation  of  mois- 
ture rising  through  the  porous  ground.^ 

Wheat  thrives  better  where  the  soil  contains  a  considerable  proportion 
of  these  alkaline  salts,  so  that  their  presence  throughout  the  Red  River 
Valley  is  one  principal  cause  of  its  superiority  in  wheat  raising;  and  this, 
grown  year  after  year,  gradually  takes  away  these  ingredients  and  pre- 
pares the  land  for  other  crops.  But  their  etfect  as  dissolved  everywhere 
in  wells  and  streams  partly  offsets  this  benefit,  and  makes  the  water  of  all 
this  region  objectionably  hard,  and  sometimes  in  wells  and  springs  notice- 
ably bitter  or  salt. 

The  hardness  of  the  water,  on  account  of  which  it  will  not  dissolve 
soap,  is  produced  by  the  carbonates  of  lime  and  magnesia,  which  it  has 
taken  up  in  soaking  through  the  ground.  The  best  way  to  provide  water 
satisfactory  for  washing  with  soap  is  by  collecting  the  rain  from  roofs.  By 
the  construction  of  cisterns,  this  soft  water,  which  also  is  preferable  for 
drinking  and  cooking,  may  be  kept  constantly  on  hand,  there  being  gener- 
all}^  a  good  supply  of  rain  in  all  seasons  excepting  winter,  when  it  falls  as 
snow. 

The  water  of  streams  and  wells  in  this  district  contains  a  small  pro- 
portion of  the  alkaline  sulphates  of  lime,  soda,  magnesia,  and  potassa,  and 
carbonate  of   soda,  though  not  usually  enough  to  be  perceptible  to  the 

'An  analysis,  by  Prof.  James  A.  Dodge,  of  an  "alkali ''  efflorescence  from  a  surface  of  till  in 
Murray  County,  southwestern  Minnesota,  showed  it  to  be  a  hydrous  sulphate  of  magnesia,  with 
slight  traces  of  soda,  potash,  and  lime.  The  proportions  of  sulphur  trioxlde  and  magnesia  were  the 
.same  as  in  epsomite  (epsom  salt),  but  it  had  less  than  half  the  percentage  of  water  of  crystallization 
required  by  epsomite.  (Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Tenth  Annual  Report,  for  1881, 
p.  202.) 

Efflorescent  saline  matter  from  one  of  the  alkaline  lakes  of  the  Missouri  Coteau,  analyzed  by 
Dr.  G.  M.  Dawson,  contained  of  sulphate  of  magnesia,  49.06  per  cent;  sulphate  of  soda,  47. 7S  per 
cent;  and  cliloride  of  sodium,  O.7.")  jier  cent.  A  similar  saline  incrustation  from  the  Souris  Valley, 
examined  qualitatively  by  Dr.  Dawson,  showed  only  the  magnesic  and  sodic  sulphates.  (Geology 
and  Kesources  of  the  Forty-ninth  Parallel,  p.  293.) 


SOURCES  OF  THE   ARTESIAN  WATER  SUPPLY. 


525 


taste.  These  waters,  however,  more  readily  than  pure  water,  decompose 
the  wooden  curbing,  which,  being  the  most  convenient  and  cheapest 
material,  is  too  commonly  used  in  this  region,  destitute  of  stone  quarries. 
The  wooden  well-curbing,  which  is  commonly  pine,  soon  contaminates  the 
water,  and  when  such  wells  are  left  stagnant  or  only  drawn  from  slightly, 
the  water  becomes  too  foul  in  smell  and  taste  to  be  drunk,  even  by  cattle, 
and  it  may  be  the  cause  of  sickness,  as  intestinal  diseases  and  typhoid 
fevers,  before  reaching  this  stage.  Let  such  wells  be  pumped  so  as  to  fill 
them  with  new  water  every  day,  and  these  offensive  qualities  are  princi- 
pally removed.  If  bricks,  stone,  or  cement  pipe  are  used  for  lining  wells, 
and  the  water  in  them  is  frequently  renewed  by  being  largely  di-awn  from, 


I 


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'tACUSr^"^£^=^  Ar^o  ■=  Al    L  Uu/AL  ~CIA  yS  1^=^^ 


^yjr-Z'Xic'::^^:.-^ 


ry'S}=-J^A'r£ff^0^A.9i^!i  ^\4AY£rffis^    ano.'.'. 


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_^V£INS),or.  SAND.  .AN^D     -GffA^  ve-i.'  ■'.  >_ 


b;."",-'"'.'.-"'';  v;~: 


'■•-.'d7'^';-;'  o''':<s 


>^''Li;''i'-'.'''.".''.'.'^^^W-:--^r^'-'.».''.o'''-i'^^'.',w;^'  ''''•' 


Fia.  31,— Diagram  indicating  the  jtrobable  relationsliip  of  aoiircea  of  ai-tesian  water  at  Grandin,  N.  Dak. 

it  is  generally  wholesome  and  palatable,  and  is  well  adapted  for  nearly  all 
uses,  excepting  for  washing  with  soap,  as  before  mentioned,  and  for  steam 
boilers,  in  which  the  large  amount  of  scale  deposited  from  it  in  evaporation 
is  objectionable.^ 


SOURCES    OF    THE   ARTESIAN  WATERS. 

The  narrow  areas  that  may  be  sometimes  occupied  by  the  sand  and 
gravel  layers  in  the  drift  sheet  yielding  artesian  water,  or  the  thin  and  in 
some  places  entirely  deficient  condition  of  these  layers,  is  illustrated  by  the 

'See  two  articles  by  Prof.  N.  H.  WiuebBll.  on  "The  water  supply  of  the  Red  River  Valley," 
Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Sixth  Annual  Report,  for  1877,  pp.  0-42,  and  Niuth  Annual 
Report,  for  1880,  pp.  166-174. 


526  THE  GLACIAL  LAKE  AGASSIZ. 

diffei'eut  depths  at  which  a  flow  of  water  was  first  encountered  by  four 
wells  in  the  village  of  Grandiu,  N.  Dak.  These  wells,  whose  probable 
relationship  in  their  supplies  of  water  may  be  nearly  as  shown  in  fig.  31, 
are  on  an  area  only  about  50  rods  in  extent,  and  their  several  depths  are 
105  feet,  158  feet,  187  feet,  and  248  feet.  Either  the  upper  water-bearing 
beds  here  are  narrow,  like  a  stream  course,  so  that  they  were  not  found  by 
the  deeper  wells,  or,  if  they  exist  as  sheets  of  great  width  as  well  as  length, 
they  are  in  some  parts  thinned  out,  allowing  the  impervious  till  above  to 
rest  on  that  below.  The  experience  in  well-boring  here  is  representative 
of  inequalities  in  depths  of  flowing  wells  near  together  in  many  other 
places.  More  frequently,  however,  water  is  obtained  from  a  nearly  uni- 
form depth  throughout  a  considerable  area,  and  it  is  then  evidently  derived 
from  a  single  broadly  continuous  stratum. 

FRESH   WATER   FROM    POROUS   BEDS   OF   THE    DRIFT   SHEET. 

Though  the  water-bearing  gravel  and  sand  inclosed  between  deposits 
of  till  often  occur  in  narrow  veins  or  in  beds  which  sometimes  thin  out, 
even  near  where  they  yield  copious  artesian  flows,  they  must  have  a  great 
extent  in  the  direction  from  which  the  water  supply  is  received,  descending 
from  levels  higher  than  the  Red  River  Valley  plana,  where  the  flowing 
wells  are  situated.  At  least,  this  must  be  the  case  where  the  water  is  fresh 
or  only  very  slightly  saline,  as  at  Grandin  and  in  all  the  southern  part  of 
the  valley  as  far  northward  as  the  vicinity  of  Crookston,  in  Minnesota,  and 
Blanchard,  in  North  Dakota,  and  in  a  large  district  of  Manitoba,  including 
Winnipeg  and  the  Mennonite  reserve  east  of  the  Red  River. 

Upon  the  higher  lands  adjoining  both  sides  of  this  valley  the  water  of 
rains  is  partly  absorbed  by  percolation  into  the  drift  sheet,  chiefly  tlu-ough 
the  most  sandy  and  gravelly  layers.  Thence  it  passes  in  these  porous 
veins  and  beds  downward  to  the  valley  plain,  where  it  is  heavily  pressed 
by  the  head  of  water  filling  their  upper  portions.  When  a  boring  pene- 
trates the  impervious  overlying  beds  of  alluvial  and  lacustrine  clay  and 
of  till  the  water  usually  rises  with  a  strong  flow  above  the  surface  (fig.  32). 
If  the  height  and  pressure  of  its  head  are  inadequate  for  this,  it  rises  in  the 


SALINE   WATEE  FEOM  THE  DAKOTA  SANDSTONE. 


527 


pipe  to  a  permaneut  level,  below  wliicli  iu  most  cases  it  cau  not  be  lowered 
by  pumping,  as  a  continual  supply  is  received  from  the  distant  portions 
of  the  subterranean  reservoir. 

SALINE  AND  ALKALINE  WATEK  FROM  THE  DAKOTA  SANDSTONE. 

North  of  Crookston  and  Blanchard  to  the  international  boundary  and 
in  the  south  edge  of  Manitoba  the  water  of  the  artesian  wells,  almost  with- 
out exception,  tastes  distinctly  saline  and  alkaline.     It  seems  very  probable 


I300 


lOOC 


loo 


Fig.  32.— Section  across  the  Red  Eiver  Valley,  showiug  the  water  supply  of  its  fresb  artesian  wells.    Horizontal  scale, 
15  miles  to  an  inch. 

that  the  water-bearing  beds  of  that  large  portion  of  the  Red  River  Valley 
differ  widely  in  the  origin  of  their  water  supply  from  the  foregoing.  Instead 
of  deriving  their  water,  like  the  fresh  artesian  wells,  from  rainfall  upon 
higher  parts  of  the  drift  surface  contiguous  to  the  Red  River  Valley,  there 
seem  to  be  good  reasons  for  beUeving  that  the  brackish  water  is  mainly 


Baset^tfieffocAy  Ainn^. 

Cretaceous    Series 

The  6rea-t  Plains 


^      Surfaced  o/'G/ac/a/ Or/ff 

COTSAU     & 


Fig.  33 — Section  from  the  Rocky  Mountains  to  the  Red  River  Valley,  showing  the  water  supply  of  its  saline  artesian 
wells.    Horizontal  scale,  150  miles  to  an  inch. 

from  the  Dakota  sandstone,  which  forms  the  base  of  the  Cretaceous  series  in 
the  upper  Missouri,  Assiniboine,  and  Saskatchewan  basins,  coming  tln-ough 
that  sandstone  from  its  outcrops  on  the  flanks  of  the  Rocky  Mountains 
and  Black  Hills,  and  permeating  upward  into  the  drift  of  the  Red  River 
Valley  from  areas  where  this  sandstone  is  the  underlying  bed-rock  (fig.  33). 
That  the  saline  artesian  waters  found  within  the  basin  of  Lake  Agassiz 


528  THE  GLACIAL  LAKE  AGASSIZ. 

come  from  these  distant  sources  is  indicated  by  the  artesian  wells  obtained 
farther  west  in  North  and  South  Dakota,  which  also  need  to  be  somewhat 
particularly  described  here,  since  they  are  intimately  related  with  the  saline 
springs  and  flowing  wells  of  the  Red  River  Valley. 

Belationshl])  to  the  artesian  wells  of  Devils  Lake  and  the  James  Biver 
Valley. — Deep  artesian  wells  of  somewhat  saline  and  alkaline  water,  like 
that  of  the  part  of  the  Red  River  Valley  just  described,  are  obtained  on  a 
belt  that  extends  across  North  and  South  Dakota  from  Devils  Lake  to 
Yankton  and  Vermillion,  including  the  greater  part  of  the  James  River 
basin.  Wherever  borings  along  this  belt  have  i^enetrated  to  the  Dakota 
sandstone,  the  lowest  Cretaceous  formation  in  the  upper  Missom-i  region, 
artesian  water  has  been  found.  Probably  as  many  as  200  wells  have  been 
bored,  then-  depths  ranging  from  900  to  1,550  feet,  except  in  the  southern 
part  of  the  James  and  Vermillion  valleys,  where  many  wells  are  only  600 
to  750  feet  deep,  and  a  few,  the  farthest  southeast,  are  between  300  and 
400  feet  in  depth.  These  wells  are  mostly  5  or  6  inches  in  diameter,  and  their 
strong  pressure,  commonly  trom  50  to  175  pounds  per  square  inch  at  the 
surface,  makes  them  valuable  not  only  for  fire  hydrants  but  also  to  furnish 
power  for  manufacturing  purposes.  Several  wells  have  been  bored  at 
Aberdeen,  and  five  years  ago  fifteen  wells  were  in  use  in  Yankton.  The 
pressure  of  the  wells  in  Yankton  is  sufficient  to  raise  the  water  129  feet, 
and  in  numerous  places  along  the  middle  portion  of  the  James  River  Valley, 
as  Huron,  Redfield,  and  Aberdeen,  the  pressure  con-esj^onds  to  a  rise  of  more 
than  400  feet  above  the  surface. 

The  sections  of  these  deep  wells  in  North  Dakota  and  on  the  high 
land  between  the  James  and  Missouri  rivers  in  South  Dakota  include, 
beneath  the  di-ift,  the  Fort  Pierre,  Niobrara,  and  Fort  Benton  divisions  of 
the  Cretaceous  series;  but  along  the  lower  part  of  the  James  River  and 
on  the  Vermillion  erosion  during  the  Tertiary  era  removed  the  upper 
portion  of  these  beds,  leaving  only  the  Fort  Benton  shales  or  a  part  of 
that  formation  over  the  Dakota  sandstone. 

At  Devils  Lake,  Avhere  an  artesian  well  was  bored  in  1889,  about  6 
feet  above  the  depot,  or  1,470  feet  above  the  sea,  the  section  was  as  follows: 


SECTIONS   OF   ARTESIAN   WELLS.  529 

Section  of  well  at  Devils  Lake, 

Feet. 

Glacial  drift,  till  as  on  the  surface 25 

Dark  shale,  nearly  alike  through  its  whole  thickness,  including  the  Port  Pierre 

and  Fort  Benton  formations,  with  no  noticeable  calcareous  beds  at  the 

intermediate  Niobrara  horizon 1,  403 

Gravel,  of  granitic  iiebbles  up  to  a  half  inch  in  diameter,  firmly  cemented  Avith 

nodular  pyrite 3 

Dakota  sandstone,  or  rather  a  bed  of  loose  sand,  very  fine,  white,  or  light  gray, 

the  base  of  which  was  not  reached 80 

Total 1, 511 

From  the  sandstone,  at  the  depth  of  1,470  feet,  brackish  artesian 
water  came  up  with  a  rush,  but  sand  soon  filled  the  pipe  so  that  the  supply 
became  small.  It  is  from  this  level  that  the  present  flow  comes,  through 
narrow  slits  cut  in  'the  pipe.  The  boring  was  continued  40  feet  deeper, 
but  no  such  strong  flow  was  obtained  below.  In  July,  1889,  when  the 
well  was  completed,  it  supplied  1,800  ban-els  of  water  in  twenty -four 
hours,  or  about  40  gallons  per  minute,  the  diameter  of  the  pipe  being  8 
inches,  reduced  to  3.^  in  the  lower  portion.  The  stream  flowing  away  was 
then  turbid  Avith  the  exceedingly  fine  particles  of  sand  brought  up  from 
the  bottom. 

The  Jamestown  well,  bored  in  the  winter  of  1886-87,  about  8  feet 
below  the  depot,  or  1,400  feet  above  the  sea,  went  tlu-ough  a  similar  sec- 
tion of  about  1,400  feet  of  shales,  with  no  distinctly  different  portion  to 
indicate  the  place  of  the  Niobrara  fonnation. 

At  Deloraine,  in  Manitoba,  1,644  feet  above  the  sea,  situated  close 
northwest  of  the  Turtle  Mountain  and  about  100  miles  northwest  from  the 
city  of  Devils  Lake,  an  unsuccessful  boring-  for  an  artesian  well  has  found, 
under  a  thickness  of  94  feet  of  glacial  di-ift,  a  somewhat  uniform  section  of 
shales,  largely  calcareous  in  their  lower  half,  extending  to  the  total  depth 
of  1,800  feet,  according  to  Mr.  J.  B.  Tyrrell,  of  the  Geological  Survey  of 
Canada.^  At  that  depth,  which  was  bored  during  the  years  1888  to  1890, 
the  top  of  the  Dakota  sandstone  had  not  been  reached,  so  that  it  is  known 
to  be  at  least  nearly  200  feet  lower  than  at  Devils  Lake  and  more  than 
156  feet  below  the  sea-level. 

1  Trans.,  Roy.  Soc.  Canada,  Vol.  IX,  Sec.  IV,  1891,  pp.  91-97. 
MON   XXV 34 


530 


THE  GLACIAL  LAKE  AGASSIZ. 


Artesian  ivelU  deriving  water  from  tlie  Dakota  sandstone  in  North  and  Soidh  Dakota. 


Locality. 


Devils  Lake  . . 
Jamestown  .  - . 

Oakes 

EUendale 

Britton 

Columbia 

Andover 

Groton 

Aberdeen 

Ipawich 

Mellette 

Ashton 

Doland 

Eedfleld 

Faulkton 

Hitchcock 

Huron 

Miller 

Highmore 

Harold 

"Woonsocket . . 

Letclier 

Mitchell 

Plankinton  . . . 

Kimball 

Vermillion 

MeckliDg 

Yankton 

Tyndall 

Fort  Eandall . 


Distance  on  latitude 
and  longitude  from 
the  southeast  corner 
of  South  Dakota. 


North. 


390 

305 

252 

243 

228 

216 

202 

204 

206 

204 

186 

174 

167 

166 

176 

148 

130 

140 

141 

141 

108 

97 

84 

85 

87 

20 

23 

27 

34 


Miles. 


119 

110 

80 

101 

72 

92 

72 

82 

101 

127 

101 

101 

81 

103 

132 

97 

88 

126 

148 

163 

91 

85 

79 

102 

126 

24 

31 

46 

71 

106 


Depth. 


Feet. 

1,511 

1,476 

944 

1,087 

1,004 

965 

1,070 

960 

908 

1,270 

900 

915 

950 

900 

1,210 

950 

863 

1,148 

1,552 

1,453 

750 

600 

600 

750 

1,068 

365 

338 

610 

730 

600 


Pressure 

at  surface 

per  square 

inch. 


Head  above 
surface, 
computed 
from  pres- 
sure. 


Pounds. 


95 


125 


175 

90 

'187 

175 
70 


175 


175 
175 
125 
25 
80 
153 


140 
95 
15 


Altitudes  above  the  sea. 


288 


404 
208 
432 
404 
162 


404 
404 
288 
58 
185 
353 


56 


323 
219 
35 


Source  of 
water  in 
upjter  part 
of  the  Da- 
kota sand- 
stone. 


Feet. 


0 
—76 
378 
362 
350 
339 
406 
344 
392 
260 
400 
381 
405 
395 
363 
389 
424 
439 
338 
348 
558 
700 
701 
778 
720 
785 
818 
586 
688 
660 


Surface, 

railroad  at 

statlou. 


Feet. 
1,464 
1,408 
1,322 
1,449 
1,354 
1,304 
1,476 
1,304 
1,300 
1,530 
1,300 
1,296 
1,355 
1,295 
1,573 
1,339 
1,287 
1,587 
1,890 
1,801 
1,308 
1,300 
1,301 
1,528 
1,788 
1,150 
1,156 
1,196 


Head,  com- 
puted from 
pressure. 


1,619 


1,737 


1,708 
1,684 
1,736 
1,704 
1,692 


1,411 


21,260 


1,743 
],691 
1,875 
1,948 
1,986 
1,661 


1,851 
2,007 
1,185 


1,325 


1,364 


>  The  pressure  reported  at  Ashton  is  100  or  125  pounds  less  than  would  be  expected  in  proportion  with  other  localities, 
and  at  Groton  it  is  somewhat  more.  The  discrepancy  of  the  latter,  however,  is  no  greater  than  may  be  due  to  the  superior 
permeability  of  the  water-bearing  stratum. 

^Approximate  altitude  of  high  water  of  the  Missouri  River  at  Fort  Randall. 

For  the  greater  part  of  my  notes  of  the  artesian  wells  of  South 
Dakota,  also  of  EUendale  and  Oakes,  in  North  Dakota,  I  am  indebted  to 
"Resources  of  Dakota,"  publi.shed  by  the  Territorial  commissioner  of 
immigration  in  1887,  and  to  recent  correspondence  with  Prof  Gr.  E.  Culver, 
then  of  the  University  of  South  Dakota,  and  with  Prof  C.  W.  Hall,  of 
the  University  of  Minnesota.  These  data,  with  those  obtained  by  me  at 
Devils  Lake  and  Jamestown,  I  have  placed  in  tabular  form  for  convenient 
comparison,  showing  (1  and  2)  the  distances  of  the  localities  north  and 


ARTESIAN   WELLS  IN  NOETH  AND   SOUTH    DAKOTA.  531 

west  from  the  mouth  of  the  Big  Sioux  River  at  the  southeast  corner  of 
South  Dakota ;  (3)  depths  of  the  wells ;  (4)  their  pressure  at  the  surface, 
wherever  it  has  been  obtainable,  in  pounds  per  square  inch ;  (5)  the  con-e- 
sponding  height  or  head  to  which  the  water  would  rise  above  the  surface ; 
(6)  the  altitude,  with  reference  to  the  sea-level,  of  the  source  of  the  arte- 
sian water  in  the  Dakota  sandstone ;  (7)  the  altitude  of  the  surface ;  and 
(8)  the  height  of  the  computed  head  of  water  above  the  sea. 

The  flow  of  water  from  the  Dakota  sandstone  at  Devils  Lake  is  found 
exactly  at  the  sea-level,  but  the  top  of  the  sandstone  formation  is  39  feet 
higher.  At  Jamestown  the  flow  rises  from  a  depth  of  76  feet  below  the  sea- 
level,  indicating  that  the  top  of  the  Dakota  sandstone  there  sinks  slightly 
lower  than  at  Devils  Lake.  Along  the  distance  of  8.5  miles  from  north 
to  south  between  these  points  its  level  is  probably  nearly  constant,  and 
borings  at  intervening  towns,  as  New  Rockford  and  Carnngton,  will  doxibt- 
less  find  artesian  water  at  or  slightly  below  the  sea-level.  Farther  south 
the  top  of  the  sandstone  and  its  water  supply  are  found  throughout  a 
large  district  of  South  Dakota  and  the  south  edge  of  North  Dakota  at 
a  plane  from  250  to  450  feet  above  the  sea.  Continuing  still  southward, 
from  Woonsocket  to  the  Missouri  River  the  water-bearing  stratum  rises  to 
altitudes  from  558  to  818  feet  above  the  sea,  the  highest  levels  being  at 
Meckling  and  Vermillion,  the  most  southeastern  localities  of  this  list. 

The  same  southeastward  ascent  of  the  Dakota  sandstone  reaches  to 
its  outcrops  on  the  southwest  side  of  the  Missouri  in  Dakota  County,  Nebr., 
whence  its  name  is  derived,  opposite  to  the  southeast  corner  of  South 
Dakota.  There,  and  at  other  extensive  outcrops  in  western  Iowa  and  east- 
ern Nebraska,  having  approximately  the  same  elevations  as  the  surface  at 
Vermillion  and  Yankton,  the  water  coursing  through  this  sandstone  finds 
outlet  in  springs;  and  these  avenues  of  discharge  explain  the  gradual 
reduction  in  the  altitude  of  the  head  of  water  above  the  sea-level  as  the 
series  of  wells  is  followed  from  north  to  south  and  from  west  to  east. 
Somewhat  uniform  altitudes  of  1,619  to  1,743  feet  are  recorded  as  the 
heights  to  which  water  would  rise  in  pipes  for  all  the  wells  where  pressure 
is  reported,  from  Jamestown  to  Huron  and  Woonsocket,  excepting  those 
west  of  Huron,  which  will  be  considered  later,  and  the  well  at  Ashton, 


532 


THE  GLACIAL  LAKE  AGASSIZ. 


where  the  reported  pressure  is  probably  eiToneous,  lacking  100  pounds  or 
more  of  its  triie  amount.  At  Hitchcock  the  head  of  water  has  a  computed 
altitude  of  1,743  feet  above  the  sea;  18  miles  to  the  south,  at  Huron,  it 
is  1,691  feet;  22  miles  farther  south,  at  Woonsocket,  it  is  1,661  feet;  and 
81  miles  still  farther  south,  at  Yankton,  it  is  only  1,325  feet.     Fig.  34  illus- 


Fig.  34. — Section  showing  the  series  of  artesian  wells  from  De\ils  Lake  and  Jamestown  southward  to  Yankton  and 
Vermillion.    Horizontal  scale,  75  miles  to  an  inch. 

trates  this  relationship  of  the  series  of  artesian  wells  extending  from  north 
to  south  in  the  James  River  Valley. 

Equally  distinct  gradients  of  the  plane  of  water  head  are  found  descend- 
ing from  west  to  east  on  and  near  the  latitudes  of  Huron  and  Yankton. 
Thus  at  Harold,  75  miles  west  of  Hm'on,  the  head  is  1,986  feet  above  the 
sea;  at  Highmore,  15  miles  east  of  Harold,  it  is  1,948  feet;    at  Miller  it 


Fig.  35. — Section  showing  the  series  of  artesian  wells  from  Harold  eastward  to  Huron.    Horizontal  scale,  15  mileB  to 
an  inch. 

has  declined  73  feet  in  a  distance  of  22  miles  farther  to  the  east;  and  in 
the  38  miles  thence  to  Huron  it  falls  184  feet  more.  The  relationship  of  the 
wells  at  these  places  is  shown  in  Fig.  35.  From  Kimball  to  Plankinton,  in 
24  miles  from  west  to  east,  the  water  head  declines  156  feet-.  Between  Fort 
Randall  and  Yankton,  in  a  distance  of  60  miles  from  west  to  east,  this  plane 


ARTESIAN  WELLS  IN  NORTH  AND   SOUTH   DAKOTA.  533 

descends  at  least  40  feet,  but  the  descent  is  more  if  the  well  at  Fort  Ean- 
dall  is  at  a  considerable  height  above  the  Missouri  River.  In  26  miles  from 
Tyndall  eastward  to  Yankton,  the  water  head  sinks  probably  150  or  200 
feet.  In  the  next  22  miles  eastward  to  Vermillion  the  descent  is  140  feet. 
This  feature  of  the  artesian  water  supply  is  caused,  as  before  stated,  by  its 
outlets  through  springs  in  outcrops  of  the  Dakota  sandstone,  which  begin 
30  to  40  miles  southeast  of  Vermillion  and  extend  thence  southeast  and 
south. 

All  the  eastern  outcrops  of  the  Dakota  sandstone  are  lower  than  the 
upper  portions  of  the  James  River  basin  and  the  wells  farther  west  at  High- 
more  and  Harold.  These  outcrops,  therefore,  can  not  be  the  sources  from 
which  the  sandstone  receives  its  artesian  water,  but,  as  we  have  seen,  they 
are  the  avenues  of  its  natural  outflow.  We  must  look  instead  to  the  western 
outcrops  of  this  formation,  where  it  skirts  the  Black  Hills  and  exposes  its 
upturned  edges  along  the  base  of  the  Rocky  Mountain  ranges,  for  the  areas 
upon  whicli  the  water  is  carried  downward  into  the  sandstone.  Thence  we 
know  this  stratum  to  be  continuous  beneath  the  plains  to  the  James  River 
Valley,  for  there  are  no  nearer  or  other  inlets  from  which  the  copious  sup- 
ply of  the  artesian  wells  can  come.  At  a  plane  of  similar  or  greater  depth 
an  artesian  reservoir  exists  beneath  much,  if  not  all,  of  the  country  west- 
ward to  the  mountains.  The  gradients  of  the  altitudes  to  which  the  water 
of  wells  is  capable  of  rising  along  east-to-west  lines  in  South  Dakota,  as  at 
Huron,  Miller,  and  Highmore,  are  approximately  the  same  as  the  average 
westward  ascent  of  the  country,  demonstrating  this  western  origin  of  the 
water  supply,  and  indicating  that  such  wells  may  be  obtained  upon  an 
extensive  region  of  the  arid  plains. 

The  quantities  of  alkaline  matter  and  salt  dissolved  in  the  water  of  these 
wells  usually  give  it  a  brackish  taste,  and  make  it  unfit  for  drinlcing  by 
people  and  for  ordinary  domestic  uses;  but  it  is  drunk  freely  by  cattle  and 
horses,  with  no  unfavorable  effects.  These  mineral  ingredients  seem  to  have 
been  derived  from  the  Cretaceous  shales,  and  probably  in  part  from  beds 
in  the  Dakota  formation,  with  which  the  water  has  been  in  contact  durinsr 
its  slow  percolation  hundreds  of  miles  through  the  sandstone.  They  are 
the  same  in  kind  and  similar  in  amount  with  the  mineral  matter  of  Devils 


534  THE  GLACIAL  LAKE  AGASSIZ. 

Lake,  concentrated  by  evaporation  without  outlet  from  the  water  of  inflow- 
ing streams  and  springs,  which  bring  vevj  small  amounts  of  these  salts 
dissolved  from  the  drift  and  Cretaceous  shale  of  the  adjoining  country. 

Much  shale  gravel  and  detritus,  rich  in  sulphates,  are  present  in  the 
glacial  drift  over  nearly  the  entire  Red  River  basin,  and  the  percolating 
rain  water  found  by  the  fresh  artesian  wells  in  the  di-ift  of  the  southern 
and  northern  ends  of  the  Red  River  Valley  has  acquired  minute  quantities 
of  alkaline  and  saline  matter.  But  where  its  proportion  is  large,  as  in  the 
brackish  water  of  the  wells  from  Crookston  and  Blanchard  northward  to 
the  edge  of  Manitoba,  it  seems  impossible  that  so  remarkable  difi'erence 
can  be  due  to  diversity  in  the  material  of  the  di-ift,  or  to  longer  time  and 
better  opportunity  afforded  to  the  water  for  such  impregnation  while  perco- 
lating tlu'ough  porous  beds  or  veins  in  the  di-ift.  The  saline  and  alkaline 
artesian  waters  of  the  drift  gravel  and  sand  along  this  central  portion  of 
the  Red  River  Valley  therefore  appear  to  be  received  mainly  from  the 
same  Dakota  sandstone  which  supplies  the  deep  wells  of  the  James  River 
Valley. 

Several  wells  in  the  vicinity  of  Casselton,  Blanchard,  and  Mayville, 
ranging  from  317  to  404  feet  in  depth,  pass  tlu'Ough  the  drift  and  enter  a 
very  fine  white  sandstone,  probably  the  Dakota  formation,  from  which  they 
obtain  flows  of  brackish  water.  About  a  dozen  miles  east  of  Blanchard 
the  drift  was  found  to  have  a  total  thickness  of  310  feet,  below  which  a 
boring  went  107  feet  into  exceedingly  fine  white  sandstone,  finding,  how- 
ever, no  artesian  water,  apparently  because  of  the  very  close  texture  of  the 
rock.  The  top  of  the  sandstone  in  these  wells  is  650  to  575  feet  above 
the  sea.  If  it  is  the  Dakota  sandstone,  as  seems  probable  and  nearly  cer- 
tain, it  has  an  ascent  of  about  600  feet  in  75  miles  east  from  the  meridian 
of  Devils  Lake  and  Jamestown,  rising  in  its  approach  toward  the  Silurian, 
Cambrian,  and  Archean  areas  of  Minnesota  and  Manitoba.  Along  a  line 
about  1 3  miles  north  of  the  international  boundary  the  top  of  the  Dakota 
sandstone  ascends  eastward  from  a  depth  at  Deloraine  exceeding  156  feet 
below  the  sea-level  to  a  depth  of  only  320  feet  below  the  surface  at  Morden, 
where  it  is  encountered  658  feet  above  the  sea.^     The  Dakota  sandstone 

'J.  B.  Tyrrell,  "Three  deep  wells  in  Manitoba,"  Trans.,  Roy.  Soc.  Canada,  Vol.  IX,  Sec.  IV,  1891, 
pp.  91-104. 


SOURCES   OF  SALT  IN  ARTESIAN  WELLS.  535 

there  rises  more  than  800  feet  iu  a  distance  of  106  miles  from  west  to  east. 
It  appears  thus  to  be  the  bed  rock,  on  which  the  drift  is  deposited,  beneath 
extensive  tracts  in  the  middle  part  and  on  the  western  border  of  the  Red 
River  Valley,  discharging  there  its  alkaline  and  saline  artesian  water  into 
the  permeable  beds  of  gravel  and  sand  in  the  drift  sheet,  whence  it  rises  in 
the  brackish  wells  of  that  district. 

Relationship  to  artesian  wells  at  Totver  City  and  Grafton,  N.  Dak.,  Hum- 
boldt, Minn.,  and  Morden  (not  artesian)  and  Bosenfeld,  Manitoba. — An  artesian 
well  at  Tower  City,  50  miles  east  of  Jamestown,  is  4  feet  lower  than  the 
depot,  behig  1,168  feet  above  the  sea.  Its  depth  is  670  feet,  through  drift, 
163  feet;  Cretaceous  shales,  with  occasional  beds  of  sandstone,  502  feet; 
and  quicksand,  into  which  the  boring  advanced  only  5  feet.  Salty  and 
alkaline  water  outflows  9^  gallons  per  minute,  and  is  capable  of  rising  33 
feet  above  the  surface.  The  scanty  flow  and  low  head  of  this  well  suggest 
that  the  water-bearing  stratum  may  be  inclosed  within  the  Fort  Benton 
shales ;  but  its  altitude,  500  feet  above  the  sea-level,  accords  with  that  of  the 
sandstone  reached  by  wells  at  Blanchard  and  Mayville,  so  that  more  prob- 
ably it  is  the  top  of  the  Dakota  formation.  The  plane  of  the  head  of  water 
supplied  from  this  formation  would  show  a  marked  descent  northeastward, 
as  is  thus  indicated  at  Tower  City,  still  more  distinctly  at  Morden  (page 
81),  and  in  less  degree  at  Devils  Lake,  in  comparison  with  Jamestown 
and  Ellendale,  if  there  are  abundant  natural  outlets  of  this  artesian  water 
along  the  Red  River  Valley,  as  appears  to  be  true,  by  springs  rising  through 
the  drift.  These  brackish  springs  occur  on  many  of  the  streams  tributary 
to  the  Red  River  both  in  North  Dakota  and  Minnesota,  the  most  remark- 
able being  on  Forest  and  Park  rivers,  which  therefore  were  formerly  called 
the  Big  and  Little  Salt  rivers.^ 

Beneath  the  central  part  and  western  side  of  the  Red  River  Valley, 
the  Dakota  sandstone,  forming  the  base  of  the  great  Cretaceous  series  which 
is  penetrated  by  the  wells  at  Deloraine,  Devils  Lake,  and  Jamestown, 
probably  abuts  in  many  places,  with  horizontal  or  only  slightly  inclined 
stratification,  upon  the  eroded  western  edges  of  the  similarly  almost  hori- 
zontally bedded  Silurian  rocks.     Undoubtedly  a  part  of  the  salt  contained 

'Translations  of  their  Ojibway  names,  according  to  Eev.  J.  A.  Gilfillan,  Fifteenth  Annual  Report, 
Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  for  1886.  p.  463. 


536  THE  GLACIAL  LAKE  AGASSIZ. 

in  the  water  of  the  artesian  wells  in  the  drift  of  the  Red  River  Valley,  as 
well  as  of  its  saline  springs,  has  been  supplied  directly  from  tlie  underlying 
Silurian  formations,  which,  as  stated  in  Chapter  III,  yield  an  artesian  flow 
of  brackish  water  at  Grafton,  N.  Dak ,  and  flows  of  rather  strong  brine  at 
Humboldt,  Minn.,  and  Rosenfeld,  Manitoba.  The  relationship  of  these 
rocks  to  the  adjacent  Dakota  sandstone  suggests  a  question  whether  possi- 
bly some  of  the  salt  in  the  water  of  this  sandstone  at  Morden,  Tower  City, 
Devils  Lake,  and  along  the  James  River  Valley  may  have  come  from  the 
same  source.  The  gradients  of  the  head  of  the  artesian  wells  of  North  and 
South  Dakota  show,  however,  by  their  descent  toward  the  east  and  south- 
east, that  the  currents  of  water  running  through  the  Dakota  sandstone  come 
from  tlie  Rocky  Mountains  and  Black  Hills,  and  that  they  find  egress  by 
springs  in  the  Red  River  Valley  and  in  the  valley  of  the  Missouri  south- 
east of  Yankton.  On  account  of  the  greater  weight  of  saline  than  of  fresh 
water,  this  subterranean  drainage  of  the  vast  western  plains  may  have  con- 
tribvited  much  to  the  quantity  and  strength  of  the  brine  contained  in  the 
deep  reservoir  of  the  Silurian  strata  beneath  the  bed  of  Lake  Agassiz.  It 
seems  to  me,  therefore,  more  likely  that  the  Dakota  sandstone  has  been 
chiefly  a  giver  rather  than  a  recipient  of  salt,  in  its  relation  to  the  Silurian 
formations  penetrated  by  the  Humboldt  and  Rosenfeld  wells. 

ANALYSES  OF  WATERS  FR03I  WEEES,  STREAMS,  AND  EAKES  IN  THE 
RED   RIVER  VALEEY  AND  THE  ADJOINING  REGION. 

The  following  analyses  show  the  composition  of  the  mineral  matter 
which  had  been  held  in  solution  and  was  left  after  evaporation  by  the 
waters  of  several  wells,  streams,  and  lakes  in  this  region.  The  first  column 
in  each  analysis  gives  the  proportion  of  the  several  ingredients  to  the 
weight  of  the  natural  water  in  parts  per  million.  In  the  second  column 
their  percentages  are  stated,  and  the  third  notes  the  weight  of  each  in 
grains  per  standard  gallon  of  the  United  States,  containing  231  cubic 
inches.  Nos.  1,  3  to  7,  and  10  to  12  were  analyzed  under  the  direction  of 
Prof.  James  A.  Dodge,  of  the  University  of  Minnesota,  by  his  assistants, 


ANALYSES  OF   ARTESIAN  WATERS. 


537 


Mr.  C.  F.  Sidener^  and  Prof.  William  A.  Noyes."  No.  2  was  analyzed  by 
Mr.  Gr.  Clu-istian  Hoffman,'  and  Nos.  8  and  9  by  Mr.  Frank  D.  Adams,*  of 
the  Geological  Sm-vey  of  Canada.  The  hardness  of  these  waters,  when 
noted,  is  in  degrees  of  Wanklyn's  scale. 


1.   Brine  from,  the  artesian  ivell  at  Humboldt,  Minn.  (pagA  74-76). 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina 

Carbonate  of  iron 

Siilpli.ite  of  lime 

Sulphate  of  magnesia  . 
Carbonate  of  magnesia 
Cliloride  of  magnesium 
Chloride  of  calcium  . . . 
Chloride  of  potassium  . 
Chloride  of  sodium. . . . 
Phosphoric  acid 

Total 


Parts  per 
million. 


208.5 

40.9 

18.5 

1,  990.  2 

1,  236. 4 
1,347.5 
1, 567.  6 

2,  684. 0 
724.3 

47, 402. 5 
Traces. 


57, 220.  4 


Percent- 
age. 


0.4 
0.1 


3.5 
2.1 
2.4 
2.7 
4.7 
1.3 
82.8 


100.0 


Grains  per 
gallon. 


12.15 

2.38 

1.08 

110.  08 

71.12 

78.60 

91.44 

1.56. 55 

42.26 

2,  764.  99 


3,  336.  65 


The  proportion  of  common  salt  in  the  total  dissolved  solids  of  this 
water  is  82.8  per  cent,  or  about  five-sixths.  "This  gives  it,"  as  Prof  N.  H. 
Winchell  remarks,  "more  than  the  average  per  cent  of  chloride  of  sodium 
found  in  the  Michigan  brines,  while  the  total  solid  matter  in  solution  is 
only  from  one-third  to  one-half  as  much."^ 

'Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Thirteenth  Annual  Report,  pp.  43,  98, 101, 102  (Nos.  1, 
10,  and  11);  and  Fourteenth  Annual  Report,  p.  .345  (No.  4).     Am.  Geologist,  Vol.  VI,  p.  218  (No.  3). 

^Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Eleventh  Annual  Report,  pp.  172-175  (Nos.  5,  6,  7, 
and  12). 

^Geol.  and  Nat.  Hist.  Survey  of  Canada,  Annual  Report,  nevr  series.  Vol.  I,  pp.  13-15  M. 

<Ibid.,  Report  of  Progress  for  1878-79,  pp.  8-11  H.  (Reduced  to  refer  to  United  States  standard 
gallon.     Compare  pp.  7-12  C.) 

'Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Thirteenth  Annual  Report,  p.  43. 


538 


THE  GLACIAL  LAKE  AGASSIZ. 

2.  Brine  from  the  artesian  well  at  Bosenfeld,  Manitoba  {pages  78-SO). 


Ingredients  dissolved  in  the  water. 

Parts  per 
million. 

Percent- 
age. 

Grains  per 
gallon. 

12.6 

Traces. 

77.7 

4, 151. 1 

Traces. 

1,  722.  5 

398.2 

417.9 

36,  497. 1 

0.73 

Carbonate  of  irou      

Carbonate  of  lime 

0.2 
9.6 

4.53 
242. 05 

Borate  of  soda         

Cliloride  of  iiiao"nesiuiu ... 

4.0 

0.9 

1.0 

84.3 

100.  44 

23.22 

24.37 

2,  128. 15 

Chloride  of  calciuiu 

Ohloride  of  potR^siiiT" 

Total 

43, 277. 1 

100.0 

2, 523.  49 

Bromine  and  iodine  are  both  present,  the  former  apparently  exceeding 
the  latter.  The  proportion  of  magnesium  assumed  to  be  in  combination 
with  them  as  bromide  and  iodide  amounts  to  59.6  parts  per  million.  This 
brine  is  slightly  purer  than  that  of  the  Humboldt  well,  but  its  content  of 
salt  is  one-fourth  less. 


3.    Water  from  the  artesian  well  at  Jamestown,  N.  Dak.  (page  529). 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina 

Carbonate  of  iron 

Carbonate  of  lime 

Sulphate  of  lime 

Sulphate  of  magnesia 

Sulphate  of  soda 

Sulphate  of  potash  . . . 
Chloride  of  sodium  . . . 
Phosphates 

Total 


Parts  per 
million. 


35.7 

3.5 

2.2 

188.0 

249.0 

154.2 

1,  139.  4 

81.5 

369.1 

Traces. 


2, 222. 6 


Percent- 
age. 


1.6 
0.2 
0.1 
8.5 

11.2 
6.9 

51.2 
3.7 

16.6 


Grains  per 
gallon. 


2. 0823 

.2041 

.1283 

10.  6743 

14. 5241 

8.  9944 

66.  3602 

4.  7523 

21.  5296 


100. 0  I     129.  2496 


Hardness  of  this  water,  21  degrees.  In  the  test  for  the  amount  of  its 
dissolved  organic  matter,  by  Tidy's  permanganate  method,  the  oxygen 
consumed  in  three  hours  was  0.7  part  per  million. 


ANALYSES  OF  ARTESIAN   WATEES, 


539 


The  water  of  the  Jamestown  well  tastes  strongly  brackish,  and  is 
representative  of  many  of  the  wells  of  the  James  River  Valley  deriving 
their  supply  from  the  Dakota  sandstone;  but  some  are  less  brackish  and 
even  palatable,  while  some  others  are  more  saline.  According  to  Prof. 
Henry  Montgomery,  of  the  University  of  North  Dakota,  the  water  of  the 
artesian  well  at  Devils  Lake  (page  529)  contains  approximately  0.25  per 
cent  of  chloride  of  sodium  (common  salt),  as  compared  with  the  whole 
weight  of  the  water,  or  seven  times  more  than  the  Jamestown  water;  and 
about  0.37  per  cent  of  sulphate  of  soda  (Glauber's  salt),  or  nearly  three 
and  a  half  times  more  than  is  shown  in  the  foregoing  analysis. 

4.    Water  from  the  Miniwaste  artesian  well,  Browns  Fallei/,  Minn,  (page  S9). 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina 

Protoxide  of  iron 

Sulphate  of  lime 

Sulphate  of  magnesia. 

Sulphate  of  soda 

Phosphate  of  lime 

Chloride  of  sodium 

Chloride  of  potassium 

Carbonic  acid 

Nitrates 


Total. 


Parts  per 
million. 


13.0 

0.4 

0.7 

51.8 

27.9 

1,452.G 

5.0 

912.  7 

Traces. 

Traces. 

Traces. 


2,464.1 


Percent- 


0.5 


2.1 
1.1 

.59.0 

0.2 

37.1 


Grains  per 
gallon. 


0. 7583 

.0233 

.0408 

3. 0215 

1. 6270 

84.  7302 

.2916 

58. 2378 


100. 0  I    143. 7305 


The  test  for  organic  matter,  with  permanganate  of  potash,  showed 
1.63  parts  oxygen  consumed  per  million.  This  water  has  a  considerable 
reputation  for  its  aperient  and  alterative  medicinal  properties.  Its  content 
of  Glauber's  salt  is  about  one-fourth  more  than  in  the  water  of  Jamestown, 
and  it  has  two  and  a  half  times  as  much  common  salt. 


540 


THE  GLACIAL  LAKE  AGASSIZ. 


5.   Water  from  an  artesian  well  at  Carman,  Polk  County,  Minn. 


Ingredients  dissolved  iu  the  water. 


Silica 

Alumina  and  oxide  of  iron 

Carbonate  of  lime 

Carbonate  of  magnesia  . . . 

Carbonate  of  litbia 

Carbonate  of  potash 

Nitrate  of  potash 

Carbonate  of  soda 

Sulphate  of  soda 

Borax 

Chloride  of  sodium 

Bromide  of  potassium 

Iodide  of  potassium 

Total 


Farts  per 
million. 


26.2 

1.5 

88.6 

52.9 

Traces. 
11.5 

Traces. 
73.8 
47.5 

Traces. 
156.5 

Traces. 

Traces. 


458.5 


Percent- 
age. 


5.7 

0.3 

19.4 

11.  G 


Grains  per 
gallon. 


1.529 

.087 

5.171 

3.087 


2.5 

.671 

16.2 
10.1 

4.308 
2.773 

34.2 

9. 134 

100.0 


26. 760 


Nitrates,  absent;  phosphates,  absent.  The  test  with  joermanganate 
showed  0.85  parts  oxygen  consumed  by  organic  matter  per  1,000,000 
water.  Hardness,  12.5  degrees.  This  well  is  less  saline  and  alkaline  than 
many  others  on  both  sides  of  the  Red  River  thence  northward  to  the 
international  boundary;  but  it  is  more  so  than  most  of  the  artesian  wells 
southward  in  this  valley. 

6.    Hater  from  the  Red  River  at  Fergus  Falls,  Minn. 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina  and  oxide  of  iron 

Carbonate  of  lime 

Carbonate  of  magnesia  . . . 

Carbonate  of  lithia 

Carbonate  of  potash . 

Bromide  of  potassium 

Nitrate  of  potash 

Nitrite  of  potash 

Carbonate  of  soda 

Sulphate  of  soda 

Chloride  of  sodium 

Total 


Parts  per 
million. 


14.3 

1.2 

101.0 

71.4 

Traces. 

4.2 

Traces. 

Traces. 

Traces. 

5.8 

1.8 

2.3 


202.0 


Percent- 


7.0 

0.6 

50.0 

35.4 


2.1 


2.8 
0.9 
1.2 


100.0 


Grains  per 
gallon. 


0. 83412 

.  06999 

5. 89133 

4. 16476 


. 24919 


.  33831 
.  10499 
.  13456 


11. 78725 


ANALYSES  OF  WATEE  OF  RED  ElVEE. 


541 


Iodine,  absent;  phosphoric  acid,  traces.  The  permanganate  test  showed 
1.4  parts  oxygen  consumed  by  organic  matter  per  1,000,000  water.  Hai'd- 
ness,  9.5  degrees. 

7.   Water  from  the  Bed  River  at  St.  Vincent,  Minn. 


lugredients  dissolved  in  the  water. 


Silica 

Oxide  of  iron  ami  alumiua 

Carbonate  of  lime 

Sulphate  of  lime 

Nitrate  of  lime 

Carbonate  of  magnesia  . . . 

Phosphate  of  lithia 

Sulphate  of  potash 

Nitrite  of  potash 

Bromide  of  potassium 

Sulphate  of  soda 

Chloride  of  sodium 

Total 


Parts  per 
million. 


13.0 

1.0 

97.8 

35.7 

1.1 

81.9 

0.6 

8.7 

Traces. 

Traces. 

21.7 

22.9 


284.4 


Percent- 
age. 


4.6 

0.4 

34.3 

12.6 

0.4 

28.7 

0.2 

3.1 


7.6 
8.1 


100.0 


Gr.iius  per 
gallon. 


0. 75829 
. 05833 

5. 70467 

2. 08238 
. 06416 

4.  77723 
.  03499 
. 50747 


1. 26576 
1.  33576 


16.  58904 


Iodine,  absent.     In  the  permanganate  test  the  oxygen  required  for 
oxidation  was  3.5  per  milUon.     Hardness,  19  degrees. 


8.   Water  from  the  Bed,  River  one-fourth  of  a  mile  above  the  mouth  of  the  Asslniboine, 


Ingredients  dissolved  in  the  water. 


Parts  per 
million. 

Percent- 
age. 

105.6 

20.4 

154.3 

29.8 

96.3 

18.6 

14.5 

2.8 

67.4 

13.0 

79.  9 

15.4 

518.0 

100.0 

Grains  per 
gallon. 


Carbonate  of  lime 

Carboniite  of  magnesia 

Sulphate  of  lime 

Sulphate  of  potash. ... 

Sulphate  of  soda 

Chloride  of  sodium 

Total 


6.155 
8.996 
5.614 
.846 
3.938 
4.656 


30. 205 


The  hardness  of  this  water  is  23.9  degrees. 


542  THE  GLACIAL  LAKE  AGASSIZ. 

9.   Water  from  the  Assiniboine  River  one-fourth  of  a  mile  above  its  junction  with  the  Hcd  River 


Ingredieuts  dissolved  iu  the  water. 


Carbonate  of  lime 

Carbonate  of  magnesia 

Sulphate  of  potash 

Sulphate  of  soda 

Chloride  of  sodium 

Total 


Parts  per 
million. 


173.0 

137.7 

13.2 

117.4 
46.8 


488.1 


Percent- 


35.4 
28.2 

2.7 
24.1 

9.6 


100.0 


Grains  per 
gallon. 


10.090 

8.027 

.769 

6.845 

2.730 


28. 461 


The  hardness  of  this  water  was  20.6  degrees,  behig  slightly  less,  like 
its  total  content  of  mineral  matter,  than  in  the  water  of  the  Red  River  at 
the  confluence  of  the  Assiniboine.  The  stage  of  rivers,  whether  in  partial 
flood  or  at  the  low  level  of  seasons  of  drought,  decides  to  a  large  extent 
whether  their  dissolved  ingi-edients  are  little  or  much.  The  amount  of 
clayey  mud  and  fine  sand  borne  along  mechanically  suspended  iu  the 
water  of  rivers  is  vastly  increased  by  their  rise  and  stronger  currents  in 
times  of  floods;  but  the  amount  of  matter  dissolved  in  the  water,  which  is 
the  only  portion  considered  in  these  analyses,  is  then  much  less  than  at 
their  lowest  stages,  when  they  hold  little  or  no  mud  in  suspension. 

Although  in  the  waters  of  the  last  two  analyses  the  Red  River  had 
more  dissolved  matter,  both  mineral  and  organic,  than  the  Assiniboine,  the 
average  proportion  of  the  latter  throughout  the  year  is  probably  the  greater. 
Samples  of  water  from  these  streams,  similarly  collected  by  Dr.  Robert  Bell 
and  analyzed  by  Dr.  Baker  Edwards,  showed  only  about  two-thirds  as 
much  of  both  mineral  and  organic  matter  in  the  Red  River  as  in  the  Assini- 
boine.^ These  samples  were  collected  October  18,  1873,  and  those  of 
analyses  8  and  9  were  taken  on  October  26,  1879.  Recent  rains  in  larger 
amount  on  one  of  these  basins  than  on  the  other,  or  differences  iu  their 
volume  due  to  lack  of  rainfall,  probably  account  for  these  different  results 
of  the  analyses! 


'Geol.  and  Nat.  Hist.  Survey  of  Canada,  Eeport  of  Progress  for  1878-79,  pp.  7-12  C. 


ANALYSES  OF  WATERS. 

10.   Water  from  Big  Stone  Lake. 


543 


Ingredients  disaolved  in  the  water. 


Silica 

Carbonate  of  irou 

Carbonate  of  lime 

Carbonate  of  magnesia 
Sulphate  of  magnesia  . 

Sulphate  of  potash 

Sulphate  of  soda 

Chloride  of  sodium 

Phosphates 

Total 


Parts  per 
miilion. 


106. 50 

2.20 

110.50 

63.00 

148. 05 

12.48 

95.63 

15.12 

Traces. 


553.  48 


Percent- 
age. 


19.2 

0.4 

20.0 

11.4 

26.7 

2.3 

17.3 

2.7 


100.0 


Grains  per 
gallon. 


6.  2090 

.1283 

6. 4455 

3. 6748 

8. 6358 

.7280 

5.  5781 

.8819 


32. 2814 


Oxyg'eu  cousuined  by  organic  matter  in  the  permanganate  test,  1.32 
parts  per  million.  This  Avater  is  remarkable  for  its  large  proportion  of 
silica. 

11.   Water  from  the  Mississippi  Biver  at  Brainerd,  Minn. 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina 

Carbonate  of  iron 

Carbonate  of  lime 

Carbonate  of  magnesia 
Carbonate  of  potash . . . 

Carbonate  of  soda 

Sulphate  of  soda 

Chloride  of  sodium 

Nitrates 

Phosphates 

Total 


Parts  per 
million. 


18.2 

3.9 

4.2 

111.1 

27.7 

6.0 

19.4 

3.0 

1.5 

Traces. 

(') 


Percent- 


9.3 
2.0 
2.2 
57.1 
14.2 
3.1 
9.9 
1.5 
0.7 


195.0 


100.0 


(Jrains  per 
gallon. 


1. 0616 
.2275 
.2453 

6. 4787 

1. 6169 
.3499 

1. 1292 
.1749 
.0875 


11.  3715 


'  Slight  traces. 

Oxygen  required  for  the  oxidation  of  organic  matter  by  the  perman- 
ganate test,  1.28  parts  per  million. 


544 


THE  GLACIAL  LAKE  AGASSIZ. 


12.    Water  from  Lake  Siqierior,  collected  at  Grand  Marais,  Minn. 


Ingredients  dissolved  in  the  water. 


Silica 

Alumina  and  oxide  of  iron. 

Carbonate  of  lime 

Carbonate  of  magnesia 

Carbonate  of  lithia 

Carbonate  of  potasb 

Nitrate  of  potash 

Nitrite  of  potash 

Carbonate  of  soda 

Sulphate  of  soda 

Chloride  of  sodium 


Total 


Parts  per 
million. 


0.5 

Traces. 

30.8 

9.1 
Traces. 

1.9 

0.2 

(') 
0.5 
0.6 
2.1 


45.7 


Percent- 
age. 


1.1 


67.4 
19.9 


4.2 
0.5 


1.1 
1.3 

4.5 


100.0 


Grains  per    ( 
gallon. 


0. 02917 


1.  79656 
. 53080 


.  11083 
.  01167 


.  02917 
.  03499 
.  12249 


2.  66568 


'  Minute  traces. 


Iodine  and  bromine,  absent;  phosphates  and  borates,  absent.  The  test 
with  permanganate  showed  0.35  parts  oxygen  consumed  by  organic  matter 
per  1,000,000  water. 

Hardness,  3.5  degrees,  so  low  amount  being  less  than  the  average  of 
"soft"  well  and  spring  waters. 

This  analysis  of  the  very  pure  water  of  Lake  Superior  (perhaps  even 
more  remarkable  for  its  small  content  of  organic  than  of  mineral  matter) 
is  presented  for  comparison  with  the  waters  of  the  Red  River  Valley.  It 
contains  less  than  one-fourth  as  much  mineral  matter,  and  only  slightly 
more  than  this  proportion  of  organic  matter,  as  compared  with  the  water 
of  the  Upper  Mississippi  River  at  Brainerd.  These  proportions,  in  compar- 
ison with  the  water  of  Big  Stone  Lake,  are  respectively  one-twelfth  and 
about  one-fourth.  The  Red  River  at  Fergus  Falls  has  about  four  and  a 
half  times  as  much  mineral  matter  as  Lake  Superior,  and  four  times  as  much 
organic  matter;  but  at  St.  Vincent  these  proportions  are  increased  respec- 
tively to  6  and  10,  and  the  former  is  still  further  raised  to  11  at  the  mouth 
of  the  Assiniboine  and  the  city  of  Winnipeg. 

The  artesian  water  at  Carman  has  ten  times  as  much  mineral  matter 
and  two  and  a  half  times  as  much  organic  matter  as  Lake  Superior,  and 
these  proportions  for  the  Jamestown  artesian  well  are  respectively  about 


IRRIGATION  BY  ARTESIAN  WELLS.  545 

49  and  2.  But  a  far  greater  contrast  is  afforded  by  the  water  of  the  Hum- 
boldt artesian  well,  which  contains  about  1,250  times  more  dissolved  mineral 
matter  than  Lake  Superior,  while  the  ratio  of  their  salinity  is  22,572  to  1. 
It  should  be  remarked,  however,  that  these  comparisons  are  made  with 
one  of  the  purest  lakes  of  the  world.  Few  analyses  of  the  natural  waters 
of  lakes  and  streams  show  so  little  dissolved  mineral  and  organic  matter. 
Reindeer  Lake,  lying  in  the  great  Archean  area  of  central  Canada,  north 
of  Lake  Winnipeg,  is  one  of  these,  for  it  has  only  about  three-fifths  as 
much  dissolved  matter  as  Lake  Superior;  and  an  equally  small  amount,  or 
even  slightly  less,  is  found  in  the  waters  of  Bala  Lake,  in  Wales,  and  Loch 
Katrine,  in  Scotland.^ 

USE  OF  ARTESIAK  WATER  FOR  IRRIGATIO]V. 

Within  the  agricultural  eastern  half  of  both  North  and  South  Dakota, 
occasional  years,  and  sometimes  two  or  three  years  in  succession,  have  much 
less  rainfall  than  the  average.  These  years  of  drought  and  consequent 
complete  or  partial  failure  of  crops  have  been  exceedingly  discouraging  to 
the  people  of  these  States,  checking  the  immigration  which  poured  in  rapidly 
during  a  series  of  comparatively  wet  years,  with  magnificent  crops,  from 
1880  to  1885.  The  great  fertility  of  the  soil,  however,  when  supplied  with 
sufficient  moisture,  causes  the  questions  to  be  asked:  Can  artificial  irriga- 
tion be  provided  during  seasons  of  drought  on  this  area!  and,  Can  artesian 
wells  be  profitably  used  for  this  purpose? 

These  questions  are  not  of  so  great  importance  for  the  Red  River 
Valley,  where  no  drought  has  severely  affected  the  crops  during  the  fifteen 
or  twenty  years  since  the  earliest  settlement  and  development  of  farming, 
as  for  the  closely  adjacent  country  on  the  west,  from  the  vicinity  of  Devils 
Lake  southward  along  the  Sheyenne  and  James  rivers,  where  many  farmers 
sowing  50  to  200  acres  or  more  in  wheat  harvested  little  or  nothing  dur- 
ing the  very  dry  years  of  1887  to  1889.  But  within  the  Red  River  Valley 
portions  of  the  summers  of  these  and  other  years  have  been  so  day  that 
artificial  irrigation  would  have  benefited  the  grain  fields.    In  a  few  instances 

'  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1880-81-82,  pp.  6,  7  H. 
MON   XXV 35 


546  THE  GLACIAL  LAKE  AGASSIZ. 

and  on  a  small  scale  tlie  water  of  artesian  wells  in  tliis  valley  lias  been ' 
ajDplied  to  jjatches  of  garden  vegetables  and  other  crops  near  dwellings. 

Will  it  be  profitable,  on  a  larger  scale,  to  store  the  water  of  artesian 
wells  in  reservou-s  for  use  in  the  season  of  growing  crops,  and  especially 
during  severe  di-oughts!  To  this  inquuy  we  may  reply  by  computing  the 
amoimt  of  water  needed  for  irrigating  a  given  space,  as  a  quarter-section  of 
160  acres,  the  usual  area  of  a  homestead.  Allowing  a  depth  of  12  inches 
of  water  for  this  use  during  the  growing  season,  the  year's  supply  of  water 
from  a  well  flowing  100  gallons  per  minute  is  required,  without  allowance 
being  made  for  leakage  or  evaporation  fi'om  the  reservoir.  The  Devils 
Lake  well  would,  therefore,  imgate  only  64  acres,  and  the  Jamestown 
well,  flowing  375  gallons  per  minute,  will  water  less  than  a  section  1  mile 
squai-e.  But  each  of  these  wells  cost  about  S7,000,  to  which  must  be  added 
the  cost  of  the  construction  of  reservoirs  and  imgating  ditches,  placing  the 
expense  of  such  water  sujjply  fai-  beyond  its  prospective  value  for  ordinary 
agricultui-e. 

Unusual  difficulties  were  encountered  in  boring  these  wells,  which  are 
the  deepest,  excepting  only  the  well  at  Highmore,  in  the  list  on  page  530. 
With  the  experience  now  acquhed,  they  might  probably  be  bored  for  half 
as  great  expense;  and  shallower  wells,  from  600  to  1,000  feet  deep,  as  at 
Yankton,  Woonsocket,  and  Aberdeen,  may  be  bored  and  piped  at  a  cost 
ranging  from  S800  to  $1,500.  The  still  shallower  artesian  wells  in  the 
di-ift  of  the  Red  River  Valley,  varying  in  depth  from  35  feet  to  250  or  300 
feet,  cost  from  $50  to  8200  or  $300.  Each  of  these  wells  could  supply 
water  sufficient  for  the  irrigation  of  a  few  acres,  and  those  ha-vang  the  most 
copious  flow  would  irrigate  50  acres  or  more  if  their  water  were  stored  in 
reservoirs  for  use  only  during  the  summer. 

An  important  objection,  however,  against  the  use  of  this  water  for 
u-rigation  seems  to  lie  in  its  dissolved  alkaline  and  saline  matter,  which 
must  be  left  in  the  soil.  After  continued  use  duiing  many  years,  the 
residuum  from  the  water  would  quite  certainly  prove  injurious  to  crops,  so 
that  the  land  would  become  worthless.  Such  results  have  attended  imga- 
tion  with  only  very  slightly  sahne  Avater  on  the  allu\aal  plains  of  the  arid 
northwestern  provinces  of  India.     The  proportion  of  sulphate  of  soda  in 


IRRIGATION  BY  ARTESIAN  WELLS.  547 

streams  flowing-  dowu  from  the  Himalayan  range  and  in  canals  taking 
water  from  them  varies  from  9  to  43  parts  in  a  million,  and  the  proportion 
of  common  salt  is  from  0.23  to  15  parts;  yet  under  the  dry  climate  of  north- 
western India  the  natural  evaporation  of  so  nearly  pure  water,  and  its  use 
in  irrigation,  have  caused  extensive  tracts  of  land  formerly  productive  to 
become  bari'en.^ 

Neither  the  water  of  the  Red  River  at  St.  Vincent  nor  that  of  the  very 
slightly  brackish  artesian  well  at  Carman  is  more  suitable  for  ii-rigation 
than  the  Himalayan  waters  mentioned;  while  the  bitter  water  of  the  James- 
town and  Devils  Lake  artesian  wells,  on  account  of  its  larger  content  of 
common  salt  and  of  Glauber's  and  Epsom  salts  (sulphates  of  soda  and 
of  magnesia),  would  be  far  worse  for  the  land,  in  which  saline  and  alkaline 
matter  would  be  accumulated  by  the  evaporation  of  the  water. 

Concerning  the  results  following  the  use  of  artesian  water  for  irrigation 
in  the  Red  River  Valley,  Prof  C.  W.  Hall,  of  the  University  of  Minnesota, 
writes  me  as  follows,  under  date  of  January  14,  1891: 

Officers  of  our  agricultural  experiment  station  say  that  in  tlie  Red  River  Valley 
experiments  already  show  that  ground  watered  from  artesian  wells  is,  after  three  or 
four  years,  almost  wholly  unsuited  to  raising  the  current  crops.  Several  large  farmers 
iu  that  region  have  sunk  wells  to  secure  a  supply  of  water  for  gardens,  and  have  found 
that  very  soon  their  garden  patches  must  be  moved  to  other  places. 

In  many  portions  of  the  great  arid  region  of  the  western  plains  and 
the  Cordilleran  mountain  belt  sufliciently  pure  water  for  irrigation  is  furnished 
by  streams,  especially  where  they  flow  from  neighboring  mountains,  and  less 
frequently  by  artesian  wells.  But  it  must  be  reluctantly  said  that  within 
the  agricultural  area  of  Lake  Agassiz,  and  upon  the  adjoining  district  of 
North  and  South  Dakota,  neither  the  rivers  nor  artesian  wells  can  supply 
water  well  adapted  for  application  to  the  land  during  a  long-  series  of  years. 
Fortunately,  irrigation  is  not  greatly  needed  in  any  part  of  this  lacustrine 
area;  and  on  the  adjoining  region  the  bountiful  harvests  of  the  years  of 
copious  rainfall  may  fully  offset  the  occasional  failure  of  crops.^ 

'Medlicott  and  Blanfoid,  Manual  of  the  Geology  of  India,  pp.  413-415. 

^  See  Rejiort  of  the  Special  Committee  of  the  United  States  Senate  on  the  Irrigation  and  Reclama- 
tion of  Arid  Lands,  four  volumes  (bound  in  two),  Washington,  1890. 


548  THE  GLACIAL  LAKE  AGASSIZ. 

NOTES   OF  ARTESIAN  AND   COMMON  WELLS. 

The  following  notes  present  many  sections,  showing  in  detail  the  char- 
acter and  order  of  the  drift  deposits  penetrated  by  artesian  and  common 
wells  in  the  Red  River  Valley  and  on  the  contiguous  higher  eastern  and 
western  borders  of  Lake  Agassiz.  A  few  of  these  wells  pass  tlu-ough  the 
drift  and  afford  information  of  the  underlying  Cretaceous  and  Lower  Silu- 
rian strata.  Among  the  many  records  of  wells  gathered  during*  the  survey 
of  the  shore-lines  of  Lake  Agassiz,  this  list  selects  in  general  the  most  note- 
worthy, as  those  remarkable  for  their  depth,  for  abundant  flow  or  sudden 
rise  of  water,  or  for  their  sections  of  the  drift  and  older  formations.  At 
the  same  time  the  ordinary  or  average  depth,  or  the  range  in  depth  of  other 
wells,  and  the  quantity  and  quahty  of  their  water  supply,  are  often  stated, 
with  the  prevailing  character  of  the  drift,  lacustrine,  and  alluvial  beds. 

Two  classes  of  wells,  peculiar  respectively  to  the  beach  ridges  and  the 
deltas,  may  be  here  described  once  for  all,  so  that  no  examples  of  them  will 
appear  in  the  following  pages.  Many  farmers,  in  selecting  the  site  for  their 
dwellings,  have  wisely  placed  them  on  the  beautifully  rounded,  wave-like 
ridges  of  gravel  and  sand  which  mark  the  former  shores  of  Lake  Agassiz. 
Their  houses  have  dry  cellars,  and  their  wells,  after  passing  10  to  15  feet 
through  the  gravel  of  the  beach  to  the  underlying  till,  usually  obtain  an 
ample  supply  of  excellent  water,  healthful  for  people,  horses,  and  cattle  to 
drink.  The  water  is  hard,  or  unfit  for  washing  with  soap,  because  of  the 
presence  of  the  carbonates  of  lime  .and  magnesia  dissolved  from  the  gravel, 
sand,  and  till;  but  it  is  usually  free  from  alkaline  matter,  such  as  is  often 
contained  in  the  water  of  this  district  when  it  has  percolated  tlu-ough  the 
till  jand  its  inclosed  sand  iind  gravel  beds  for  longer  distances. 

On  the  deltas  of  Lake  Agassiz  wells  also  usually  have  water  of  the 
same  good  quality,  but  it  is  found  at  a  gi-eater  depth.  Usually  on  these 
tracts  the  depth  to  water  ranges  from  20  to  50  feet;  but  on  the  Pembina 
delta  and  near  the  outer  border  of  the  Assiniboine  delta  a  thickness  exceed- 
ing 100  feet  in  their  porous  sand  and  gravel  deposits  must  be  penetrated 
before  the  plane  of  saturation  or  of  water  running  thi-ough  their  basal 
portion  is  reached.     Along  the  foot  of  the  frontal  slope  of  the  delta,  or 


WELLS  ON  DELTAS.  549 

on  the  banks  of  the  river  which  has  cut  tlirough  it,  this  water  issues  in  large 
sjjrings. 

The  deepest  well  of  this  class  noted  was  on  the  Pembina  delta,  close 
north  of  the  river,  in  the  northeast  quarter  of  section  36,  township  163, 
range  67,  where  T.  R.  McLaughlin  had  dug  145  feet  and  bored  30  feet 
farther,  in  all  175  feet,  not  yet  obtaining  any  water.  The  material  of  the 
section  was  all  water-deposited  sand  and  gravel,  some  layers  having  pebbles 
as  large  as  3  or  4  inches  in  diameter,  but  mostly  sand.  A  well  only  a  half 
mile  to  the  north,  on  the  same  delta,  has  a  good  supply  of  water  at  the 
depth  of  30  feet,  and  in  some  places  springs  issue  only  halfway  down 
the  bluffs  inclosing  the  Pembina  River,  which  flows  some  225  feet  below  the 
delta  plateau  upon  which  these  wells  are  situated.  Here  and  there  some- 
what clayey  layers  in  the  delta,  or  otherwise  comparatively  impervious 
beds,  caiise  water  to  be  found  by  wells  before  reaching  the  bottom  of  the 
sand  or  the  general  plane  of  its  saturation.  More  frequently  wells  must 
go  to  that  plane,  lying  in  the  Pembina  delta  mostly  at  a  great  depth,  as 
exemplified  also  by  the  wells  mentioned  on  page  359. 

The  arrangement  of  these  notes  is  in  three  divisions,  under  the  States 
of  Minnesota  and  North  Dakota  and  the  Province  of  Manitoba.  In  each  of 
the  two  States  the  counties  are  taken  separately,  in  their  order  from  south 
to  north.  In  each  county  the  geographic  order  of  the  townships  whose 
wells  are  described  is  from  south  to  north,  and  secondarily  from  east  to  west; 
and  in  any  township  where  several  wells  are  noted  they  are  given  in  the 
numerical  order  of  the  sections  (as  shown  on  page  11). 

It  has  been  found  most  convenient  to  note  in  the  same  list  both  the 
artesian  and  the  common  wells.  The  artesian  water  often  flows  only  to 
the  surface  or  a  few  feet  above  it;  and  many  other  wells  obtain  water 
which  rises  from  a  deep  source  to  within  a  few  feet  below  the  surface, 
coming  evidently  from  the  same  beds  that  elsewhere  supply  the  flowing 
wells.  Among  the  common  wells  of  less  depth  and  not  so  nearly  related 
with  the  artesian,  the  water  often,  and,  indeed,  usually,  rises  several  feet 
above  the  porous  bed  or  vein  in  which  it  is  found.  The  shallow  wells, 
however,  of  which  there  are  many  only  10  to  15  or  20  feet  deep,  generally 
are  supplied  by  the  seepage  of  surface  water. 


550  THE  GLACIAL  LAKE  AGASSIZ. 

WELLS    ON   THE    AREA    OF    LAKE    AGASSIZ    IN    MINNESOTA 

TRAVERSE   COU>'TY. 

Browns  Valley. — The  section  of  the  artesian  well  in  this  village  has  been  given 
on  page  89,  and  an  analysis  of  its  water  on  page  539. 

Doleysnwunt. — Eudolph  Heidelberger,  southeast  quarter  of  section  G:  Well,  30 
feet  deep;  till,  22  feet;  and  sand  with  water,  not  rising,  14  feet,  to  the  bottom  and 
continuing  lower. 

Emil  Heidelberger,  northeast  quarter  of  section  6 :  Artesian  well,  79  feet  deep, 
in  drift,  chiefly  till;  flow  scanty. 

Grohe. — Cyrus  B.  Stevens,  northeast  quarter  of  section  12:  Well,  GO  feet  deep; 
soil,  gravel,  and  sand,  5  feet;  till,  50  feet;  and  quicksand,  penetrated  5  feet  and  con- 
tinuing lower,  so  soft  that  the  auger  fell  3  or  4  feet.  Water,  so  alkaline  that  it  can 
not  be  used,  rose  from  this  sand  to  3  feet  below  the  surface. 

Clifton. — William  McClymond,  in  section  13,  has  two  artesian  wells,  each  about 
85  feet  deep,  in  drift.  There  are  several  other  flowing  wells,  60  to  75  feet  deep,  in  this 
northeastern  i)art  of  the  township. 

J.  T.  Blaisdell,  in  section  31,  has  two  flowing  wells.  The  one  at  the  farmhouse  is 
119  feet  deep,  bored  all  the  way  in  till,  yellowish  for  25  or  30  feet,  and  dark  bluish 
below,  hardest  in  its  lowest  6  or  8  feet,  beneath  which  water  was  struck  in  coarse 
gravel,  and  rises  to  the  surface,  overflowing;  a  good  supply.  The  other  well,  nearly  a 
mile  northeast  from  the  foregoing,  is  182  feet  deep.  Water  rises  from  quicksand  at 
the  bottom,  and  is  of  good  quality,  but  only  a  small  supply.  This  well  was  bored 
after  that  at  the  farmhouse,  so  that  water  was  expected  at  119  feet,  but  none  was 
found,  nor  was  any  layer  of  gravel  and  sand  noticed  at  that  depth. 

Wheaton. — Common  wells  at  Wheaton  are  25  to  35  feet  deep,  in  till;  water 
usually  rises  to  10  or  15  feet  below  the  surface,  and  is  mostly  alkaline;  but  the  town 
well,  in  the  middle  of  the  street,  30  feet  deep,  drained  every  day  by  its  general  use, 
has  fairly  good  water. 

Boring  for  an  artesian  town  well  went  to  the  depth  of  300  feet,  obtaining  no 
flow  at  the  surface.  This  well  found  at  200  feet  a  large  supply  of  gocd  water,  which 
rose  to  15  feet  below  the  surface.  It  came  fi'om  the  top  of  a  bed  of  sand  and  gravel 
about  10  feet  thick,  and  rose  with  such  force  that  it  filled  40  feet  of  the  pipe  with 
sand.  Next  below  was  clay,  probably  till,  about  65  feet,  lying  on  Cretaceous  shale, 
into  which  the  boring  was  continued  about  25  feet. 

Another  unsuccessful  boring  for  artesian  water  was  done  in  this  village  at  T.  E. 
Dunn's  livery  stable,  to  a  depth  of  390  feet.  Till  extended  from  the  surfiice  to  a 
depth  of  280  feet,  inclosing  layers  of  sand  and  gravel  at  130  feet  and  at  other  depths 
to  200  feet.  The  lower  110  feet  were  hard,  dark  bluish  shale,  probably  belonging  to 
the  Fort  Benton  division  of  the  Cretaceous  series. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  551 

Tintah. — Several  shallow  wells  ia  this  township  have  ample  flows  of  good  water 
from  the  drift.  The  well  at  the  railway  tank  is  48  feet  deep,  with  water  rising  only 
to  the  surface.  J.  E.  Henry  has  three  or  more  artesian  wells  at  his  extensive  farm 
buildings  near  Tintah  railway  station.  The  well  at  the  farmhouse  is  45  feet  deep, 
with  water  rising  nearly  to  the  surface,  but  not  overflowing.  At  the  barns,  about 
50  rods  southeast,  a  well  G7  feet  deei^  flows  6  inches  above  the  surface.  Another  well, 
about  halfway  between  these  two,  is  45  feet  deep,  with  water  rising  6  feet  above  the 
surface. 

Taylor. — In  the  north  edge  of  this  township,  and  near  the  Bois  des  Sioux  River, 
Mr.  Bruce  has  an  artesian  well  106  feet  deep,  flowing  3  gallons  per  minute. 

C.  M.  Harmon,  northwest  quarter  of  section  3:  Well,  73  feet  deep;  till  extends 
to  the  depth  of  70  feet,  being  yellowish  for  its  first  15  feet,  and  dark  bluish  below, 
yielding  much  alkaline  water  at  18  feet,  also  some  seeping  water  from  lower  gravelly 
streaks.  At  the  bottom,  water  of  excellent  quality  was  found  in  a  bed  of  gravel  and 
sand,  and  rose  within  a  few  minutes  to  a  level  6  feet  below  the  surface.  This  water- 
bearing bed  is  only  3  or  4  feet  thick,  as  was  shown  by  boring  deeper,  when  the  pipe 
shut  off  the  water,  and  was  therefore  lifted  back. 

David  Warriner,  section  31 :  A  boring  at  the  farmhouse  went  165  feet  in  till,  find- 
ing no  supply  of  water.  About  15  rods  distant  to  the  north,  on  land  6  feet  lower, 
another  well  went  50  feet  in  till,  to  gravel  and  sand  yielding  a  large  supply  of  good 
water,  which  quickly  rose  to  a  permanent  level  14  feet  below  the  surface. 

A  large  number  of  other  vpells  in  this  county  are  described  in  Geology 
of  Minnesota,  Vol.  II,  pp.  530,  531. 

WILKIN  COUNTY. 

Champion. — This  township  has  probably  as  many  as  thirty  artesian  wells,  ranging 
from  50  to  110  feet  in  depth,  in  the  drift.  One  of  the  earliest  bored  and  most  coijious 
in  flow  is  on  the  Fountain  Valley  Farm,  section  3,  owned  by  Col.  C.  H.  Brush  &  Co. 
This  well  is  66  feet  deep,  being  till,  56  feet,  and  sand,  10  feet,  and  continuing  deeper, 
from  which  the  artesian  flow  is  obtained.  The  diameter  of  the  pipe  is  1  foot,  reduced 
below  to  7  inches.  A  large  stream  of  very  clear,  cold  water  constantly  flows  from  this 
well,  its  estimated  volume  being  7  or  8  barrels  per  minute,  or  about  250  gallons.  The 
water  is  of  excellent  quality  for  house  and  farm  use,  but  is  hard  and  slightly  irony, 
and  deposits  a  rusty  sediment  in  the  channel  of  the  stream.    Its  temperature  is  46°  F. 

In  section  11,  nearly  2  miles  southeast  from  the  foregoing,  a  well  was  bored  to 
the  dej)th  of  about  50  feet,  and  was  left  dry  by  the  workmen  when  they  stopped  at 
night;  but  in  the  morning  it  was  found  overflowing  and  flooding  the  surrounding 
land.  In  1887  this  well  had  been  thus  running  six  years,  baffling  all  efforts  to  shut  it 
ofl',  and  spoiling  or  damaging  a  tract  equal  to  half  a  section  by  its  inundation. 


552  THE  GLACIAL  LAKE  AGASSIZ. 

George  Barnes,  northwest  quarter  of  section  14:  Artesian  well,  S3  feet  deep,  In 
till,  to  quicksand  at  the  bottom,  into  which  the  auger  fell  suddenly  2  or  3  feet,  obtain- 
ing a  very  powerful  flow  of  water. 

George  W.  Mace,  southeast  quarter  of  section  22:  Well,  107  feet  deep;  water 
rises  5  feet  above  the  surface,  but  has  only  a  feeble  flow. 

T.  B.  Bushnell,  southwest  quarter  of  section  23,  about  40  rods  east  of  the  last 
and  on  land  several  feet  higher:  Well,  105  feet;  artesian  water  rises  with  much  force, 
probably  sufBcient  to  carry  it  to  a  height  of  40  feet.  It  flows  22  gallons  per  minute 
from  a  pipe  1  inch  in  diameter. 

Nash  Brothers,  northwest  quarter  of  section  26,  about  a  half  mile  south  of  the 
last:  Well  also  105  feet;  water,  found  at  95  feet,  rises  with  similar  force,  bringing  up 
quicksand.  It  has  a  temperature  of  48°  F.,  and  is  of  the  best  quality,  being  softer 
than  the  water  of  neighboring  shallow  wells. 

In  the  southeast  quarter  of  section  34,  near  Tintah,  a  well  95  feet  deep  found 
much  lignite  in  the  upper  part  of  a  water-bearing  bed  of  sand,  into  which  the  boring 
went  5  feet,  obtaining  water  that  rises  nearly  to  the  surface. 

Campbell. — The  railroad  well  in  the  village,  260  feet  deep,  went  all  the  way  in 
till,  excepting  occasional  layers  of  sand  and  gravel,  mostly  thin,  but  at  one  place  8 
feet  thick,  from  165  to  173  feet  below  the  top.  Numerous  fragments  of  lignite  were 
found  in  the  till  of  this  well,  especially  from  125  to  150  feet,  and  they  were  abundantly 
mixed  with  the  thick  bed  of  sand  mentioned,  making  about  10  per  cent  of  the  deposit. 
Some  of  its  pieces  brought  up  from  the  depth  of  173  feet  were  incrusted  with  pyrite. 
The  lower  portion  of  the  pipe  becoming  filled  with  mud,  it  was  found  necessary  to 
liuncture  the  pipe  and  admit  water  above  the  clay  filling.  This  was  done  at  176  feet. 
The  water  rose  within  4  feet  of  the  surface.  Higher  water-bearing  veins  were  encoun- 
tered in  boring  the  well  at  125,  150,  and  165  feet. 

F.  W.  Maechler,  of  Campbell,  who  has  bored  nearly  a  hundred  deep  wells  within 
a  radius  of  5  miles,  states  that  shallow  wells,  which  are  dug  10  to  25  feet  deep,  have, 
almost  without  exception,  disagreeable  alkaline  water;  but  that  the  bored  wells,  50 
to  100  feet,  or  occasionally  more,  in  depth,  have  very  good  water,  frequently  artesian. 
At  Mr.  Maechler's  house  the  well  is  55  feet  deep;  till,  20  feet;  sand,  with  some  layers 
of  fine  gravel,  35  feet,  and  continuing  lower ;  water  rises  to  3  feet  below  the  surface. 
This  exceptionally  thick  bed  of  sand  also  supplies  water  to  several  other  wells  in  the 
village;  but  some  of  the  wells  here,  including  the  railroad  well  before  noted,  are 
wholly  till,  inclosing  no  important  sand  or  gravel  layer  and  having  no  inflow  of  water, 
for  a  depth  of  100  to  125  feet. 

W.  D.  Cross,  1  mile  northwest  from  Campbell  village:  Boring,  176  feet,  entirely 
in  till,  less  stony  in  its  lower  half  and  there  containing  streaks  of  gravel  and  sand  6 
to  12  inches  thick;  no  supply  of  water.  Another  well,  however,  124  feet  deep,  bored 
only  a  few  hundred  feet  distant,  was  quite  different,  being  till,  81  feet;  sand  and 


NOTES  OF  ARTESIAlSr  AND  COMMON  WELLS.  553 

gravel,  31  feet,  and  sandy  clay,  12  feet,  continuing  lower.  This  well  obtains  artesian 
water,  just  flowing  to  the  surface;  but  it  is  found  to  be  inexhaustible,  and  can  be 
lowered  only  a  few  feet  by  pumping. 

In  section  32  a  boring  for  Charles  Mullen  went  272  feet,  obtaining  no  water.  A 
mile  to  the  southwest,  at  Mr.  Maechler's  farmhouse,  in  the  northwest  quarter  of 
section  27,  a  well  88  feet  deep  has  water  which  rises  to  18  inches  below  the  surface 
and  can  not  be  lowered  by  pumping. 

Bradford. — Charles  Covell,  southeast  quarter  of  section  10:  Artesian  well,  50 
feet  deep ;  water  rises  15  feet  above  the  surface. 

W.  H.  Fish,  southeast  quarter  of  section  12,  on  land  20  feet  above  the  foregoing: 
Well,  49  feet,  wholly  in  till;  water,  slightly  alkaline,  rose  from  gravel  and  sand  at  the 
bottom  to  a  permanent  level  3  feet  below  tbe  surface.  This  well  was  dug  with  a 
diameter  of  5  feet,  and  was  thus  filled  almost  to  overflowing  within  ten  minutes  after 
the  water  was  reached. 

Henry  Poor,  northeast  quarter  of  section  14 :  Artesian  well,  48  feet  deep,  bored 
2  inches  in  diameter;  very  copious  flow,  not  under  control,  rising  in  a  bowl-like  spring 
about  6  feet  across,  and  running  away  in  shallow  depressions  of  the  adjoining  prairie. 

Edward  H.  Boustead,  southwest  quarter  of  section  18:  Artesian  well,  85  feet 
deep;  water  of  good  quality,  pleasant  in  taste,  and  found  to  be  healthful,  but  peculiar 
in  containing  gas.  Immediately  after  the  water  reaches  the  surface  the  gas  collects 
into  very  minute  bubbles,  so  that  the  water  for  about  a  minute  seems  to  be  filled  with 
light  gray  dust  particles,  after  which  it  quickly  becomes  clear,  as  it  also  was  on  first 
flowing  from  the  pipe. 

C.  W.  Keyes,  in  the  southwest  quarter  of  section  31,  about  a  mile  northeast  ol 
Campbell,  bas  a  flowing  well  of  good  water,  64  feet  deep.  Previous  to  this  boring,  a 
well  dug  61  feet  in  till,  supplied  mainly  with  surface  water  of  inferior  quality  from 
a  thin  bed  of  gravel  and  sand  at  21  feet,  had  been  used  several  years. 

Brechenr'ulge.— Covings,  for  artesian  wells  in  this  town  have  been  unsuccessful. 
The  drift-sheet,  chiefly  till,  inclosing  only  few  and  tbin  layers  of  sand  and  gravel,  is 
found  to  have  a  thickness  of  202  feet,  underlain  by  dark  Cretaceous  shale,  probably 
the  Fort  Benton  formation.  The  shallow  wells  are  mostly  alkaline,  and  the  water  of 
the  Eed  River,  which  is  better,  has  been  generally  used. 

Andrea. — The  drift  in  this  township  is  commonly  till  to  the  depth  of  40  or  50  feet 
or  more,  its  lowest  4  or  5  feet  being  very  "hard;  then  quicksand,  5  to  10  feet-or  more, 
into  which  the  boring  must  go  a  few  feet,  as  in  the  following  examples  of  artesian 
wells,  to  get  a  good  supply  of  water. 

L.  Manske,  northeast  quarter  of  section  10:  Flowing  well,  50  feet  deep. 

P.  H.  Funkley,  southeast  quarter  of  section  26:  Well,  60  feet;  large  flow;  rising 
10  feet  above  the  surface. 

E.  Mcintosh,  southeast  quarter  of  section  27 :  Flowing  well,  86  feet  deep. 


554  THE  GLACIAL  LAKE  AGASSIZ. 

P.  Heider,  northwest  quarter  of  section  34:  Well,  43  feet;  water  rises  4  feet 
above  the  surface. 

Alcron. — Albert  Lutti,  northeast  quarter  of  section  34:  Artesian  well,  3G  feet 
deep;  in  till,  to  gravel  and  sand  at  the  bottom;  water  of  good  quality  rises  4  feet 
above  the  surface.  Another  flowing  well  in  the  southeast  quarter  of  this  section  is 
only  34  feet  deep. 

McCauleyville. — The  two  following  wells  are  in  the  village,  about  25  feet  above 
the  low-water  stage  of  the  Eed  Eiver,  whose  alluvium  is  thus  known  to  reach  some  20 
feet  below  that  level. 

James  Nolan:  "Well,  33 J  feet  deep;  soil,  2J  feet;  brownish  yellow  alluvial  clay, 
26  feet;  dark  quicksand,  4  feet;  gravel  containing  shells,  like  the  bottom  of  a  lake, 
with  water,  1  foot  and  continuing  lower. 

In  Cyril  Boutiette's  well,  alluvial  clay  extended  to  the  depth  of  45  feet,  where 
was  found  a  layer  of  abundant  remains  of  rushes  and  sedges,  some  of  them  having 
their  flowering  and  fruiting  panicles  and  spikes  distinctly  preserved. 

Mitchell.— G.  R.  Cleason,  northeast  quarter  of  section  28:  Well,  27  feet;  soil,  2; 
yellowish  gray  till,  G;  gray  sand,  i  inch;  much  harder  dark  bluish  tiU,  18  feet,  con- 
taining plentiful  rock  fragments  up  to  G  inches  in  diameter;  underlain  by  sandy  black 
mud,  in  which  were  many  small  gasteropod  shells.  This  doubtless  interglacial  fossil- 
iferous  layer,  and  an  interglacial  forest  bed  found  under  12  feet  of  till  at  Barnesville, 
in  Clay  County,  both  within  the  area  that  was  covered  by  Lake  Agassiz,  show  that 
there  was  a  sufficiently  long  warm  epoch  in  the  midst  of  the  great  Ice  age  to  cause 
the  ice-sheet  to  retreat  northward  beyond  Barnesville. 

The  recession  of  the  ice  seems  referable,  as  indicated  on  page  280,  to  the  Aftonian 
stage  of  the  Glacial  period,  between  the  Kansan  and  lowan  stages  of  ice  accumula- 
tion. The  upper  part  of  the  great  channel  occupied  by  Lakes  Traverse  and  Big 
Stone  and  the  Minnesota  Eiver  was  probably  eroded  by  southward  outflow  from  the 
Eed  Eiver  Valley  at  that  time  to  a  depth  somewhat  below  the  level  of  the  upper  or 
Herman  beach  of  Lake  Agassiz,  and  was  not  subseqiiently  filled  with  drift  when  the 
ice-sheet  again  covered  the  land  far  southward  to  its  lowan  limits.  This  interglacial 
erosion  may  have  reached  below  the  levels  of  the  fossiliferous  layers  in  the  wells  of 
Mitchell  and  Barnes^^Ue,  allowing  these  parts  of  the  Eed  Eiver  Valley  to  have  a 
land  surface,  while  its  deeper  central  part  held  a  lake;  or,  more  probably,  as  I  think, 
the  valley  may  then  have  sloped  southward,  on  account  of  differential  northward 
elevation  of  the  region,  so  that  no  lake  would  be  formed  during  the.Aftonian  glacial 
recession  in  this  basin.' 

Atherton. — In  the  southwest  quarter  of  section  9,  a  well  37  feet  deep  has  water 
which  rises  3  feet  above  the  surface. 

1  Am.  Geologist,  Vol.  XV,  pp.  279-282,  May,  1895. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  555 

Michael  Starrs,  southeast  quarter  of  section  20:  "Well,  45  feet  deep,  in  till,  to 
gravel  at  the  bottom,  from  which  water  rises  to  4  feet  below  the  surface,  and  flows 
away  by  a  ditch  to  the  Deerhorn  Creek,  only  about  50  feet  distant. 

Charles  Funkhandel,  in  the  northeast  quarter  of  section  35,  has  a  well  only  11 
feet  deep,  which  yields  a  copious  artesian  flow. 

Descriptions  of  many  other  wells  in  this  county  are  given  in  Geology 
of  Minnesota,  Vol.  II,  pages  527-530. 

CLAY   COUNTY. 

Barnes  vlUe. — This  city  has  no  artesian  wells,  and  the  common  wells  are  12  to  40 
feet  deep,  mostly  in  till  which  incloses  beds  of  gravel  and  sand.  A  boring  by  John 
Marth  to  the  depth  of  150  feet,  on  the  west  side  of  the  main  street,  found  no  artesian 
water. 

Mr.  Marth  has  a  shallow  well,  13  feet  deep,  which  is  remarkable  for  its  interglacial 
forest  bed.  The  section  was  soil  (the  blackened  surface  of  the  till),  2  feet;  yellowish 
till,  10  feet;  then  quicksand,  1  foot,  containing  several  branches  and  trunks  of  trees, 
thought  to  be  tamarack,  up  to  8  inches  in  diameter,  lying  across  the  well,  which, 
together  with  the  inflow  of  water,  x)revented  further  digging. 

Rudolph  Sieber,  in  the  southwest  quarter  of  section  12,  Baruesville  Township, 
close  north  of  a  small  creek,  has  an  artesian  well  35  feet  deei),  from  which'water  rises* 
with  a  strong  flow  to  a  height  of  16  feet  or  more  above  the  surface. 

Sabin. — Angus  Murray:  Well,  about  80  feet  in  till,  to  gravel,  from  which  water 
of  excellent  quality  rose  to  a  level  only  3  or  4  feet  below  the  surface.  The  Minneapolis 
and  Northern  Elevator  Company  has  a  similar  water  supply  in  a  well  90  feet  deep. 
Other  wells  about  20  feet  deej)  in  this  village,  dug  mostly  in  beach  sand,  hsCve  good 
water. 

A.  E.  Henderson,  on  the  Pleasant  Ridge  Farm,  1  mile  north  of  Sabin,  has  a  well 
72  feet  deep,  with  water  rising  almost  to  the  surface. 

Glyndon. — In  the  southern  part  of  this  township,  3  to  5  miles  northeast  of  Sabin, 
there  are  several  artesian  wells  50  to  75  feet  deep. 

Two  borings  at  the  elevator  of  G.  S.  Barnes  &  Co.,  in  Glyndon  Village,  failed  to 
obtain  water,  and  the  augers  were  broken  in  the  till,  called  "hardpan,"  at  the  bottom. 
In  the  deeper  one  of  these  borings  a  depth  of  125  feet  was  reached,  the  section  being 
reported  as  soil,  3  feet;  quicksand,  22  feet;  dark  clay,  free  from  stones,  75  feet;  very 
hard  yellowish  till,  15  feet;  and  softer  till,  10  feet.  The  till  in  these  borings  is  said 
to  have  been  so  hard  that  only  a  tenth  as  fast  progress  could  be  made  in  it  as  in  the 
dark  alluvial  clay  above.  A  log  of  wood,  which  was  called  "cedar,"  about  a  foot  in 
diameter,  was  encountered  by  one  of  these  borings  in  the  dark  alluvium,  35  feet  below 
the  surface;  and  the  other  boring,  about  12  feet  distant,  found  "rotten  chi^js"  of  wood 


556  THE  GLACIAL  LAKE  AGASSIZ. 

at  the  same  depth.  In  the  well  at  the  railroad  engine  house,  somewhat  farther  west, 
vegetable  deposits,  including  sheets  of  turf  and  drift  wood,  were  found  at  the  depth 
of  13  to  IS  feet. 

Moorhead. — An  unsuccessful  boring  done  in  1889  by  this  city,  in  the  hope  of 
obtaining  artesian  water  or  gas,  went  to  the  depth  of  1,750  feet.  From  comparison 
and  combination  of  notes  published  by  Prof.  K".  H.  Winchell,"  with  others  supplied 
by  Mr.  John  T.  Gray  and  Prof.  C.  W.  Hall,  the  section  appears  to  have  been  as  fol- 
lows: Alluvial  and  lacustrine  deposits,  chiefly  flue  clayey  silt,  55  feet;  pebbly  clay, 
apparently  till,  55  feet;  gravel  and  sand,  35  feet,  yielding  water  which  rose  nearly  to 
the  surface;  till,  with  occasional  layers  of  sand,  75  feet,  extending  to  the  base  of  the 
drift  at  220  feet;  bluish  and  greenish  shales,  with  beds  of  sand,  145  feet,  probably 
belonging  to  the  Port  Benton  formation,  of  Cretaceous  age;  and  granitoid  and  gneissic 
rocks,  doubtless  of  Archean  age,  beginning  at  365  feet,  of  which  a  thickness  of  1,385 
feet  was  penetrated. 

Artesian  wells  in  the  drift  have  been  obtained  here  as  follows: 

At  J.  G.  Burgquist's  brickyard  a  well  165  feet  deep  flows  8  inches  above  the 
surface. 

Minneapolis  and  Northern  Elevator  Company:  Well,  200  feet  deep,  with  water 
rising  5  feet  above  the  surface.  In  another  well,  200  feet  deep,  at  Lamb  Bros.' 
brickyard,  the  water  rises  only  to  a  level  G  feet  below  the  surface. 

These  deep  wells  have  water  of  good  quality,  excepting  its  hardness,  while  the 
water  of  shallow  wells,  10  to  25  feet  deep,  coming  from  a  bed  of  sand  3  to  10  feet 
thick, .inclosed  above  and  below  by  the  alluvial  clay,  is  somewhat  alkaline.  Most  of 
the  water  used  for  domestic  purposes  in  both  Moorhead  and  Pargo  is  taken  from  the 
Red  Eiver  by  waterworks. 

At  the  Artesian  stock  farm  of  W.  R.  Tanner  &  Co.,  section  24,  Moorhead,  a  weU 
228  feet  deep  found  water  in  a  bed  of  sand  forming  the  lowest  3  feet  of  the  section, 
and  rises  2J  feet  above  the  surface.  It  is  free  from  any  saline  and  alkaline  taste,  and 
can  be  used  for  washing  with  soap.  Two  previous  borings  here  were  stopped  at  the 
depth  of  about  180  feet  by  encountering  bowlders  in  the  till.  Most  of  the  deep  wells 
within  a  few  miles  about  this  farm  get  water  in  layers  of  gravel  and  sand  inclosed  in 
the  till  at  depths  from  160  to  200  feet,  from  which  the  water  rises  to  a  few  feet  below 
the  surface,  not  overflowing. 

Kragnes. — Minneapolis  and  Northern  Elevator  Company :  Artesian  well,  155  feet 
deep ;  water  rises  4  feet  above  the  surface,  there  flowing  only  30  barrels  in  twenty- 
four  hours  from  a  2-inch  pipe;  but  this  well,  when  pumijcd,  supplies  an  abundance  of 
water,  and  can  not  be  reduced  more  than  20  feet  below  the  surface. 

Common  wells  on  farms  around  Kragnes  are  15  to  30  feet  deep. 

'Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Bulletin  No.  5,  "Natural  gas  in  Minnesota,"  1889, 
pp.  27-31. 


NOTES  OF  AETESIAN  AND  COMMON  WELLS,  557 

Georgetown. — C.  B.  Hill,  Osborne  Farm,  southeast  quarter  of  section  33:  Arte- 
sian well,  180  feet  deej);  the  water,  rising  i  feet  above  the  surface,  is  of  good  quality, 
but  uot  so  suitable  for  use  iu  the  boilers  of  steam  engines  as  the  river  water. 

Several  flowing  wells  in  the  northern  part  of  this  townshi])  range  from  165  to 
180  feet  in  depth. 

Numerous  other  records  of  welh  in  Clay  County  are  noted  in  Geology 
of  Minnesota,  Vol.  II,  pages  667-669. 

NORMAN  COUNTY. 

Perley.—  The  Minneapolis  and  Northern  Elevator  Company  has  an  artesian  well 
about  200  feet  deep.    Another  of  similar  depth  is  at  A.  T.  Aabye's  house. 

Lahe  Ida. — Ferdinand  Burkhardt,  southwest  quarter  of  section  2 :  Well,  80  feet 
deep;  yellow  till,  10  feet;  blue  till,  70  feet;  water  seeps,  filling  the  well  to  about  25 
feet  below  the  surface. 

Ada. — The  town  well,  217  feet  deep,  4  inches  iu  diameter,  supplies  a  stream 
which  partly  fills  a  1-inch  pi^ie.  It  was  bored  in  1881,  and  has  since  been  running  at 
the  rate  of  about  100  barrels  per  day.  This  water  is  very  clear,  and  forms  no  irony 
sediment.  Its  cool  temperature  (47°  F.)  and  its  excellent  quality  for  drinking  and 
domestic  uses,  being  called  soft  water,  nearly  equal  to  rain  water  for  washing,  make 
this  a  very  satisfactory  investment  for  the  town.    Its  cost  was  about  $500. 

Common  wells  of  Ada  and  its  vicinity  are  10  to  20  feet  deep.  Their  water  is 
hard,  but  is  considered  healthful  for  drinking. 

Henry  Downs,  one-fourth  of  a  mile  west  of  Ada,  has  a  flowing  well  about  90 
feet  deep. 

McDonaldsville. — S.  A.  Farnsworth,  southeast  quarter  of  section  4:  Well,  75 
feet;  soil,  3  feet;  yellow  alluvial  clay,  10  feet;  blue  clay,  alluvial  in  its  upper  part,  but 
doubtless  including  a  considerable  depth  of  till  below,  56  feet;  a  harder  portion  of 
the  till,  called  "hardj)an,"  5  feet;  gravel,  1  foot,  and  extending  lower;  artesian  water, 
of  similar  quality  and  amount  of  flow  as  the  Ada  town  well. 

Pleasant  View. — Two  artesian  wells,  similar  in  their  sections  to  the  last,  but  more 
feeble  in  flow,  were  noted  in  this  township,  namely,  one,  65  feet  deep,  on  William 
Hein's  farm,  in  the  southwest  quarter  of  section  2,  and  the  other,  70  feet  deep,  at 
F.  S.  Flower's,  in  the  southeast  quarter  of  section  22, 

Anthony. — Ole  B.  Halvorson,  section  19:  Well,  12  feet;  soil,  2  feet;  yellow  till, 
10  feet;  water  comes  from  a  layer  of  sand  6  inches  thick  at  the  bottom,  rising  6 
feet  to  its  permanent  level  in  a  half  day.  Mr.  Halvorson  has  also  bored  down 
65  feet,  finding  the  section  wholly  till,  dark  bluish  below  the  first  12  feet;  no  layers 
of  sand  and  no  additional  supply  of  water.  Common  wells  in  this  vicinity  range 
from  12  or  15  feet  to  30  feet  in  depth.  The  water  is  slightly  alkaline,  but  is  quite  tol- 
erable and  apparently  healthful  when  the  supply  is  daily  renewed  by  pumping. 


558  THE  GLACIA.L  LAKE  AGASSIZ. 

Halsfnd. — The  Minneapolis  and  Xorthern  Elevator  Company  has  an  artesian 
well,  which  is  reported  to  be  about  250  feet  deep.  The  common  wells  are  similar  to 
those  of  Anthony  in  their  depths  and  quality  of  water. 

LocMart. — This  townshij)  and  others  adjoining  it  have  many  flowing  wells,  vary- 
ing from  100  to  200  feet  in  depth. 

On  William  Fisher's  farm,  in  section  5,  three  artesian  wells  are  each  about  130 
feet  deep.  Their  water,  which  rises  4  feet  above  the  surface,  is  free  from  any  alkaline 
or  saline  taste. 

Leo  Gnadt,  section  G :  Artesian  well,  165  feet  deep,  from  which  good  water  rises 
3  feet  above  the  surface. 

At  the  buildings  of  the  Lockhart  Farm,  In  section  29,  a  well  5  inches  in  diameter 
was  bored  to  the  depth  of  142  feet  in  the  autumn  of  1880,  the  section  being  as  fol- 
lows: Soil,  2  feet;  yellow  alluvial  clay,  or  perhaps  in  part  till,  about  10  feet;  blue  till, 
130  feet,  to  sand  at  the  bottom,  from  which  water  of  excellent  quality  rose  to  the 
surface  with  a  powerful  flow.  The  water  was  allowed  to  run  in  its  full  amount  during 
a  month  or  more,  flooding  a  considerable  tract  for  a  mile  northward.  With  the  water 
much  sand  was  brought  up  and  deposited  by  the  stream  in  a  neighboring  slough,  its 
estimated  volume  being  approximately  300  cubic  yards,  sin-ead  on  the  average  a  foot 
thick  over  a  space  about  100  feet  in  diameter.  The  flow  of  this  well  was  reduced  after 
a  time  by  a  cap  and  gauge  to  a  small  stream ;  but  in  the  following  December  it  ceased, 
because  the  bottom  of  the  pipe  for  about  20  feet  had  been  compactly  filled  with  sand. 

In  July,  1881,  a  second  well  of  similar  diameter  was  bored  a  short  distance  south 
of  the  preceding.  Till  extended  to  a  depth  of  141  feet,  below  which  the  boring  went 
into  a  bed  of  sand  16  feet,  from  which  water  rose  to  15  feet  above  the  surface,  flow- 
ing through  an  inch  pipe  about  60  barrels  per  day.  Many  fragments  of  lignite,  up  to 
3  inches  long,  were  found  in  several  layers  in  the  sand  bed,  probably  a  half  bushel  of 
it  in  all  being  brought  up  as  the  boring  progressed,  but  no  lignite  was  encountered 
in  the  till.  One  piece  of  wood  3  or  4  inches  long,  with  numerous  smaller  fragments  of 
wood,  was  also  found  in  the  sand. 

Several  other  artesian  wells  similar  to  these  have  since  been  bored  on  this  farm. 
One  of  these,  about  700  feet  distant  from  the  first  well,  struck  water  at  137  feet,  which 
rose  with  a  much  stronger  and  alarming  flow,  and  soon  found  vent  also  alongside  the 
pipe,  making  a  large  hole  and  inundating  the  vicinity  of  the  farm  buildings  and  much 
adjoining  land.  To  carry  away  this  water  many  laborers  were  quickly  set  to  digging 
ditches  along  a  distance  of  several  miles  to  the  west.  After  some  two  weeks,  how- 
ever, the  heavy  flow  mostly  ceased,  becoming  principally  confined  to  the  pipe,  with 
only  a  moderate  and  controllable  quantity  coming  to  the  surface  outside  the  pipe. 

Shely. — Iver  Mlson,  in  section  14,  has  a  well  219  feet  deep,  with  water  at  first 
rising  to  the  surface,  but  afterward  to  about  4  feet  below  the  surface.  This  well 
goes  wholly  through  drift,  nearly  all  till,  but  including  occasional  thin  beds  of  gravel 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  559 

and  sand.  The  last  5  or  6  feet  were  quicksand,  extending  also  deeper,  from  wbich  tbe 
water  came.  One  and  a  lialf  miles  south  of  this  a  well  225  feet  deep  has  water  rising 
to  3  or  4  feet  below  the  surface;  and  a  half  mile  farther  south  a  well  with  similar 
water  supply  is  209  feet  deep.  Most  of  the  flowing  or  very  deep  wells  in  this  town- 
ship and  northward  are  slightly  saline,  but  Mr.  Nilson's  bas  no  such  taste,  and  is  well 
adapted  for  washing  with  soaj),  being  said  to  be  "as  soft  as  rain  water." 

The  common  wells  of  this  region  (a  belt  of  morainic  till  crossing  the  Red  River 
Valley  from  east  to  west)  are  10  to  25  feet  deep,  obtaining  water  which  seeps  from  the 
upper  part  of  the  till.  The  water,  though  hard  and  slightly  alkaline,  is  not  generally 
unhealthful  for  farm  and  house  use,  excepting  in  wells  that  are  contaminated  by  the 
decay  of  wooden  curbing.  When  these  wells  are  allowed  to  remain  stagnant,  without 
being  frequently  drawn  from  in  large  amount,  the  water  becomes  very  offensive  in 
odor  and  taste. 

POLK   COUNTY. 

Liberty. — Jacob  Stambaugh,  northeast  quarter  of  section  33:  Well,  52  feet;  soil, 
2  feet;  gravel  and  sand  of  the  McCauleyville  beach,  16  feet;  bluish-gray  till,  very 
hard,  31  feet,  to  quicksand,  from  whicli  water,  of  good  quality  but  hard,  rose  24  feet 
in  ten  minutes,  to  its  permanent  level.  Several  i)ieces  of  wood  were  found  in  the  till 
of  this  well.  Another  well  here,  only  17  feet  deep,  finds  an  ample  supply  of  water  at 
the  base  of  the  beach  gravel  and  sand. 

Beis. — At  Beltrami  station  the  Red  River  Valley  Elevator  Company  has  an 
artesian  well  110  feet  deep,  from  which  water  rises  12  feet  above  the  surface.  It 
has  no  saline  nor  alkaline  taste,  and  is  less  hard  than  the  water  of  the  neighboring 
shallow  wells. 

George  C.  Reis,  northeast  quarter  of  section  32:  Artesian  well,  147  feet  deep; 
soil,  2  feet;  yellow  till,  partly  so  hard  as  to  need  to  be  dug  with  a  pick,  8  feet;  and  dark- 
bluish  till,  also  very  hard,  137  feet,  containing  occasional  layers  of  sand  and  gravel  up 
to  6  inches  in  thickness.  Water,  of  the  same  excellent  quality  as  at  Beltrami,  rises 
12  feet  above  the  surface.  This  well  is  5  inches  in  diameter,  reduced  at  the  top  to  a 
1-inch  pipe,  from  which  the  flow  amounts  to  about  3  gallons  per  minute,  or  150  barrels 
in  twenty-four  hours. 

Russia. — Eric  Bjerk,  northeast  quarter  of  section  2:  Well,  60  feet  deep;  soil,  2 
feet;  till,  dark  bluish,  excepting  near  the  sui'face,  so  soft  that  it  could  be  all  spaded, 
58  feet,  to  dark  sand  which  extends  at  least  2  feet.  At  this  depth  the  well  was  left 
dry  by  the  workmen  at  the  end  of  their  day's  labor,  but  in  the  morning  it  was  filled 
■with  water  and  overflowing. 

L.  T.  Soule,  the  Russia  Farm,  section  19:  Well,  124  feet;  soil,  2  feet;  yellow 
alluvial  clay,  3  feet;  quicksand,  1  foot;  dark  bluish  till,  104  feet,  with  no  layers  of 
sand  or  gravel;  sand,  fine  above  and  growing  coarser  downward,  13  feet;  and  gravel, 


560  THE  GLACIAL  LAKE  AGASSIZ. 

1  foot  and  contiuuing  below.  All  tbe  saud  bed  yields  a  feeble  artesian  flow,  and  a 
strong  flow  comes  from  tbe  gravel.  It  is  hard  water,  but  excellent  for  drinking, 
having  no  alkaline  taste. 

Hammond. — W.  S.  Rattray,  northeast  quarter  of  section  15:  Well,  12  feet;  soil, 

2  feet;  yellow  alluvial  clay,  7  feet;  sand,  3  feet,  underlain  by  dark  blue  clay.  Good 
water,  becoming  3  feet  deep,  issues  from  the  lowest  foot  of  the  sand.  Other  wells  in 
this  township  are  10  to  15  feet  deep,  many  of  them  having  objectionably  alkaline 
water. 

Fairfax. — In  the  west  part  of  section  28  a  well  80  feet  deep  has  water  which  rises 
8  feet  above  the  surface.  There  are  also  several  other  flowing  wells  within  2  or  3  miles 
eastward  and  southward,  ranging  from  80  to  112  feet  in  depth. 

Nine  flowing  wells  in  the  northeast  quarter  of  section  18  range  from  185  to  205 
feet  in  depth;  and  one  in  the  southwest  quarter  of  this  section  is  173  feet  deep. 

Andover. — E.  S.  Corser,  Southside  Farm,  section  3 :  A  boring  205  feet  deep  in 
drift,  mostly  till,  obtained  no  artesian  water. 

In  the  northeast  quarter  of  section  23  an  unsuccessful  boring  to  the  depth  of  111 
feet  went  through  black  soil  IJ  feet,  alluvial  clay  18  feet;  a  vegetal  deposit  of  leaves 
and  partially  decayed  wood  3  feet;  and  then  clay,  probably  mostly  till,  to  the  bottom. 

Carman. — The  artesian  well  at  E.  S.  Corser's  elevator,  in  this  village,  is  191  feet 
deep,  being  yellowish  alluvial  clay,  11  feet;  yellowish  quicksand,  3  feet,  in  which 
shallow  wells  get  an  ample  supply  of  water,  slightly  alkaline;  and  dark  bluish  clay, 
alluvial  at  the  top,  but  soon  changing  to  till,  177  feet,  containing  occasional  thin  lay- 
ers of  sand  below  the  depth  of  160  feet  from  the  surface.  A  bed  of  fine  gravel  and 
sand  was  reached  at  the  bottom,  from  which  water  rose  to  the  height  of  10  feet  above 
the  surface,  and  flows  at  the  rate  of  100  barrels  a  day.  The  water,  of  which  an 
analysis  is  given  on  page  540,  is  very  good  for  drinking  and  for  all  farm  and  domestic 
uses.  For  washing  with  soap  and  for  use  in  engine  boilers,  it  is  much  better  than  the 
water  of  the  river.    The  cost  of  the  well,  bored  5  inches  in  diameter,  was  $600. 

CrooTcston. — Nels  Swanson,  in  the  south  edge  of  the  city,  south  of  the  Red  Lake 
Eiver:  Artesian  well,  185  feet  deep  in  till;  alluvial  clay  above  and  till  below  for  the 
greater  part  of  its  depth,  with  occasional  thin  veins  of  sand  and  gravel;  water  of  good 
quality. 

Another  flowing  well,  owned  by  B.  Sampson,  about  20  rods  north  of  the  preceding, 
is  also  185  feet  deep,  its.lowest  6  feet  being  sand. 

S.  M.  McKee,  southwest  quarter  of  section  3:  Well,  230  feet,  with  water  rising 
from  the  bottom  to  12  feet  below  the  surface. 

H.  A.  Wyand,  southwest  quarter  of  section  5:  Well,  236  feet;  till,  155  feet;  a 
harder  deposit  of  till,  called  "hardpan,"  11  feet;  fine  gravel  and  sand,  23  feet,  with 
water  rising  from  its  top  to  8  feet  below  the  siirface ;  again  till,  in  part  moister  and 
softer  than  the  higher  till,  38  feet;  and  quicksand,  6  feet,  also  continuing  lower,  from 
which  water  rises  to  IJ  feet  below  the  surface. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  561 

Harvey  Cook,  southwest  quarter  of  section  8:  Artesian  well,  about  180  feet  deep; 
water  rises  IJ  feet  above  tlie  surface. 

There  are  many  artesian  wells,  probably  not  less  than  a  hu;iclrecl,  within  a  radius 
of  10  miles  around  Crookston,  ranging  from  165  to  285  feet  in  depth,  wholly  in  the 
drift.    Most  of  them  have  excellent  water,  free  from  any  saline  or  alkaline  taste. 

Fisher. — Ked  Lake  Mills,  in  the  village:  Well,  190  feet  deep;  soil,  2  feet;  yel- 
lowish alluvial  clay,  12  feet;  quicksand,  about  1  foot,  yielding  water  of  sufficient 
amount  and  good  quality  for  common  wells ;  dark  bluish  clay,  mostly  tiU,  through  all 
the  remaining  depth  below,  except  that  it  incloses  infrequent  layers  of  sand  6  to  12 
inches  thick,  from  one  of  which,  at  the  depth  of  about  125  feet,  water  rose  to  6  feet 
below  the  surface,  but  no  artesian  flow  was  found. 

L.  Freeman,  in  the  north  edge  of  the  village:  Well,  198  feet;  alluvial  clay,  40 
feet;  and  till,  inclosing  occasional  seams  of  saud  and  gravel  up  to  1  foot  in  thickness, 
extended  thence  to  the  bottom.  Water  of  good  quality  rises  to  9  feet  below  the  siirface. 
By  tapping  the  pipe  at  a  slightly  lower  level  it  flows  to  the  milk  house  and  barnyard, 
which  are  situated  near  the  well,  on  the  slope  descending  to  the  river. 

Hugh  Thompson  and  F.  S.  De  Mers,  in  the  south  part  of  the  village:  Artesian 
well,  285  feet  deep,  mainly  till,  but  beds  of  gravel  and  sand  containing  fresh  water 
were  encountered  at  133  feet  and  190»feet,  each  of  these  beds  being  about  10  feet  thick. 
Brackish  water  from  sand  at  the  bottom  rises  to  1  foot  below  the  surface.  Though 
perceptibly  saline,  it  is  relished  by  horses  and  cattle  and  is  found  to  agree  with  them. 

It  seems  very  significant  that  this  well,  the  first  noted  with  considerable  salt 
water  in  proceeding  northward  on  the  Minnesota  side  of  the  Red  River,  is  close  to  a 
boring  by  C.  W.  Webster  in  the  southwest  quarter  of  section  14,  about  a  mile  east  of 
Fisher,  which  at  a  depth  of  300  feet  reached  a  very  fine-grained  white  sandstone, 
doubtless  the  Dakota  sandstone,  as  that  formation  is  encountered  at  a  similar  depth 
by  numerous  wells  on  the  opposite  side  of  this  vaUey  plain  in  North  Dakota.  This 
sandstone,  as  stated  in  the  earlier  part  of  this  chapter,  is  i^robably  the  source  of  the 
saline  water  commonly  obtained  by  deep  wells  in  the  drift  northward  from  the  vicinity 
of  Crookston  and  Fisher  to  southern  Manitoba. 

St.  Hilaire. — An  artesian  well  146  feet  deep,  wholly  in  the  drift,  chiefly  till,  was 
bored  about  three-fourths  of  a  mile  south  of  the  dejiot,  near  where  the  Crookston  road 
and  railway  turn  southwestward ;  good  water,  bat  scanty  flow. 

Euclid. — Two  miles  northeast  of  Euclid,  Mr.  AUen  has  a  flowing  well  about  75 
feet  deep;  water  rising  only  a  little  above  the  surface. 

In  the  village  common  wells  obtain  an  inexhaustible  supply  of  good  water  at  the 
depth  of  12  to  18  feet,  the  section  being  soil,  2  feet;  yellow  till,  spaded,  6  to  10  feet; 
and  gray  tiU,  darker  and  much  harder,  requiring  to  be  picked,  several  feet,  to  a  bed 
of  quicksand  from  which  the  water  rises  to  a  permanent  level  0  to  8  feet  below  the 
surface. 

MON  XXV 36 


562  THE  GLACIAL  LAKE  AGASSIZ. 

Keystone. — The  first  artesian  well  at  the  buildings  of  the  Keystone  Farm,  in  sec- 
tion 23,  was  bored  in  1881,  having  a  depth  of  110  feet.  The  section  was  soil,  2  feet; 
yellow  alluvial  clay,  12  feet;  sand,  yielding  considerable  water,  about  2  inches:  dark 
bluish  till,  71  feet;  and  sand  and  gravel,  25  feet.  Water  of  excellent  (juality,  without 
salty  taste  and  so  soft  that  it  can  be  used  for  washing  with  soap,  flows  at  the  rate  of 
40  barrels  per  day,  or  nearly  a  gallon  per  minute,  the  diameter  of  the  well  pipe  being 
5  inches.  During  all  the  boring  below  85  feet  water  rose  to  the  surface,  but  only  iu 
very  small  quantity,  until  a  hard  layer  of  gravel  was  reached  at  the  bottom.  Seven 
other  artesian  wells,  all  obtaining  good  water  iu  the  drift,  have  since  been  bored 
here,  ranging  in  depth  from  95  to  150  feet. 

Another  well  on  this  farm,  sunk  to  the  depth  of  250  feet,  reached  the  Dakota 
sandstone,  the  very  line  white  sand  coming  up  with  the  water  and  giving  it  a  milky 
appearance.  It  yielded  a  copious  artesian  flow  of  brackish  water,  and  was  therefore 
abandoned. 

Angus. — Several  borings  200  to  300  feet  deep  in  Angus  village  and  its  vicinity 
have  found  no  artesian  water. 

A.  D.  Andrews,  southwest  quarter  of  section  10:  Well,  82  feet;  soil,  2  feet; 
alluvial  sandy  silt,  5  feet ;  hard,  dark  bluish  till,  mostly  picked,  43  feet ;  much  harder 
till,  with  more  frequent  bowlders,  28  feet;  soft  sand  and  gravel,  1  feet  and  continuing 
lower,  from  which  good  but  hard  water  rose  immediately  to  its  permanent  level,  20  feet 
below  the  surface. 

A.  O.  Bailey,  section  27:  Well,  253  feet;  soil,  2  feet;  mainly  till  below,  with  no 
important  beds  or  veins  of  sand  and  gravel  belbre  reaching  the  bottom,  whence  an 
ample  supply  of  good  water,  like  that  of  the  less  deep  artesian  wells  on  the  Keystone 
Farm,  rose  to  10  feet  below  the  surface. 

Tabor. — The  depths  of  two  flowing  wells  in  the  southeast  part  of  this  township 
are  reported  to  be  about  1:5  and  70  feet.  Common  wells  are  mostly  10  to  15  feet  deep, 
with  copious  supply  of  healthful  water  from  sandy  layers  in  the  alluvial  clay. 

Farley. — Furlong  &  Eainsey;  southeast  quarter  of  section  27:  Two  borings  to 
depths  of  about  1(J5  feet  and  200  feet  obtained  salt  water,  which  rose  nearly  to  the 
surface,  but  is  not  used.  This  large  farm  takes  its  water  supply  from  two  shallow 
wells,  .each  12  feet  deep,  and  from  surface  pools  dug  a  few  feet  deep. 

MAESHAIL  COUNTY. 

Warren. — At  the  elevator  of  the  Warren  Manufacturing  Company  a  well  130 
feet  deep  has  slightly  saline  water,  which  rises  from  the  bottom  to  5  feet  below  the 
surface.  Its  section  was  alluvial  clay,  50  feet,  or  quite  probably  the  lower  part  of  this 
is  till;  then  a  bed  of  gravel,  10  feet,  with  much  water,  which  does  not  rise  to  the 
surface;  dark  bluish  till,  50  feet;  and  sand  and  gravel,  20  feet  and  continuing  lower. 


NOTES  OF  AETESIAK  AND  COMMON  WELLS.  563 

The  boring  for  a  town  well  showed  a  great  thickness  of  till  beneath  this  section, 
extending  to  the  depth  of  260  feet. 

L.  Loughridge,  in  the  village:  Well,  96  feet;  water  rises  to  4  feet  below  the 
surface,  and  is  capable  of  supplying  about  25  barrels  daily. 

Pembina  Farming  Company,  1  mile  southeast  of  Warren :  Well,  ISO  feet,  obtain- 
ing excellent  water,  not  saline,  which  rises  to  20  feet  below  the  surface. 

March  &  Spalding,  1  mile  west  of  the  village:  Well,  143  feet;  water  rises  to  4 
feet  below  the  surface,  supplyiug  7.5  barrels  in  tweuty-four  hours. 

The  common  wells  of  this  vicinity  are  10  to  30  feet  deep,  obtaining  usually  an 
abundant  supply  of  water,  which  is  very  hard,  but  has  little  or  no  alkaline  taste. 

Argyle. — A  boring  for  a  town  well  in  this  village,  150  feet  deep  in  drift,  chiefly 
till,  was  stopped  at  this  depth  by  a  bowlder,  having  found  no  considerable  supply  of 
water.    Gas  which  could  be  ignited  issued  from  the  depth  of  70  to  100  feet. 

Minneapolis  and  Northern  Elevator  Company:  Flowing  well,  155  feet  deep, 
with  water  rising  only  slightly  above  the  surface,  but  yielding  a  large  supply  when 
pumped.     It  is  saline,  but  is  used  for  the  engine  boiler. 

Middle  River. — William  Carrese,  section  22,  1  mile  south  of  Argyle:  Flowing 
well,  285  feet  deep ;  brackish  water  rises  2  feet  above  the  surface. 

O.  D.  Ford,  Stone  Farm,  section  33:  Flowing  well,  218  feet  deep;  water,  found  at 
185  feet,  rises  2  feet  above  the  surface;  brackish,  but  good  for  cattle. 

Bloomer. -^Ozx  the  Argyle  Farm,  section  23,  a  boring  200  feet  or  more  in  depth 
obtained  no  artesian  water. 

Wanger. — In  the  northeast  quarter  of  section  10  a  boring  found  combustible  gas 
at  80  feet. 

James  Headrick,  southeast  quarter  of  section  28:  Well,  28  feet  deep,  dug  26 
feet,  there  finding  a  cavity  2  feet  deep,  full  of  running  water,  which  passes  tlu'ough 
the  well  with  a  southwestward  current  estimated  at  2  miles  per  hour.  A  bucket 
dipping  water  is  apt  to  be  swept  away  under  the  southwest  side  of  the  weU.  The 
water  runs  over  a  bed  of  fine  gravel  and  forms  sand  bars  in  the  bottom  of  the  well, 
which  therefore  needs  to  be  ii-equently  cleared  out.  The  section  was  soil,  2  feet ;  clay, 
4  feet;  sand  and  gravel,  2  feet;  and  till,  18  feet.  Along  the  course  of  the  Tamarack 
Eiver  for  8  miles  thence  westward  to  Stephen  it  receives  many  small  springs,  issuing 
nearly  on  a  level  with  the  river ;  and  some  of  these  are  probably  formed  by  the  stream 
that  flows  through  this  well. 

Tamarack. — C.  W.  Culbertson,  section  31:  Flowing  well,  74  feet  deep;  water  rises 
10  feet  above  the  surface;  saline,  but  good  for  stock. 

Stephen. — Town  well,  about  240  feet  deep ;  water  rises  3  or  4  feet  above  the  sur- 
face, but  it  is  not  a  large  supply,  even  when  pumped  from  at  10  feet  below  the  surface; 
too  saline  for  any  use. 


564  THE  GLACIAL  LAKE  AGASSIZ. 

On  the  Stephen  Farm,  owned  by  Charles  M.  Ramsey,  another  saline  artesian 
well,  unused,  is  220  feet  deep. 

Parker. — J.  Q.  Cronkhite,  section  25:  Flowing  well,  95  feet  deep,  quite  salty 
water,  rising  about  10  feet  above  the  surface. 

Augsburg. — Wheeler  &  Culbertson,  sectiou  32:  Boring  about  300  feet  deep;  no 
supply  of  water. 

Sirmott. — John  Hughes,  northeast  quarter  of  section  28:  Well,  42  feet;  soil,  2 
feet;  soft,  stratified  alluvial  clay,  yellowish  above,  but  dark  bluish  for  the  greater 
part  of  its  thickness,  38  feet;  very  hard,  yellowish  gray  till,  dug  into  only  2  feet, 
containing  sandy  veins  or  layers,  from  which  water  seeping  into  the  well  filled  it  7 
feet  in  a  half  day.  Within  two  weeks  in  the  dry  season,  when  it  was  dug,  the  water 
rose  to  a  depth  of  30  feet.    It  is  of  good  quality,  hard,  but  with  no  saline  taste. 

KITTSON   COUNTY. 

Donaldson. — E.  N.  Davis,  in  the  northwest  quarter  of  section  29,  Davis,  close 
east  of  Donaldson  station,  has  a  flowing  well  45  feet  deep,  which  was  bored  in  1880  in 
a  quarter  of  a  day  with  au  ordinary  2-inch  auger.  Its  flow  ever  since  that  time  has 
been  nearly  constant,  at  the  rate  of  about  8  gallons  a  minute,  or  more  than  300 
barrels  daily.  The  section  was  soil,  IJ  feet;  yellowish  gray  alluvial  clay,  10  feet; 
dark  bluish  alluvial  clay,  28  feet;  hard  dark  gray  till,  5  feet;  and  a  very  hard  ferru- 
ginous layer,  one-half  foot,  from  beneath  which  the  water  rose  quickly  to  the  surface, 
bringing  up  sand  and  gravel.  The  temperature  of  the  water  is  42°  F.  Though  salty 
to  the  taste,  farm  stock  thrive  with  this  as  their  only  sui)ply  of  water,  which  they 
drink  very  freely;  and  it  has  been  used  by  people,  with  no  apparent  injury,  as  the 
only  water  for  drinking  and  cooking  through  several  weeks  of  drought.  The  height 
to  which  it  will  rise  is  known  to  be  more  than  23  feet,  at  which  height  the  flow  seemed 
to  be  undiminished.  On  stopping  the  pipe  of  this  well  the  water  issued  as  a  spring 
several  rods  distant. 

Kennedy. — A  boring  by  the  Kennedy  Laud  and  Town  Company  went  to  the  depth 
of  225  feet,  obtaining  no  artesian  water.  Below  the  alluvial  clay  of  the  surface  the 
section  was  chiefly  tiU.  Bowlders  were  observed  at  the  depth  of  45  feet,  and  bowl- 
ders and  gravel  in  the  till  were  encountered  thence  to  the  bottom.  Water  from  layers 
or  veins  of  sand  and  gravel  rose  nearly  to  the  surface,  but  was  too  saline  to  be  used. 

Shane. — The  Fort  Donaldson  Farm,  in  section  20,  has  an  artesian  well  95  feet  deep, 
with  water  likewise  so  salty  that  it  can  not  be  used.  But  some  other  deep  wells  in 
this  township  obtain  fresh  water  of  good  quality,  as  Lars  Lundgren's  well,  in  the  south- 
east quarter  of  section  7,  which  is  119  feet  deep,  with  water  rising  just  to  the  surface, 
not  overflowing. 

Halloch. — Eklund  elevator:  Well,  125  feet  deep;  alluvial  clay  above,  succeeded 
by  till  below  for  nearly  all  the  depth ;  very  saline  water  rises  from  gravel  and  sand  at 
the  bottom  to  a  permanent  level  4  or  5  feet  below  the  surface. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  565 

L.  N.  Ekluud,  a  sixth  of  a  mile  east  of  the  depot  and  elevator :  Well,  90  feet  deep ; 
also  very  salty  water,  risiiiif  to  5  feet  below  the  surface.  Another  well,  only  li  rods 
distant,  obtained  saline  water  at  80  feet,  which  rose  immediately  just  to  the  surface, 
not  overflowing. 

L.  B.  Riddell,  close  west  of  Hallock  village:  Well,  71  feet  deep;  saline  water, 
not  used,  rises  to  4  feet  below  the  surface. 

Granville. — W.  J.  Ross,  in  section  7,  has  a  flowing  well  of  fresh  water,  only  .30  feet 
deep.  John  Jenkins,  jr.,  in  section  18,  a  mile  south  of  the  last,  also  has  a  flowing  well 
of  similar  depth  and  good  quality  of  water. 

Northcote. — Peter  Daly,  in  this  village,  bored  7.5  feet,  obtaining  no  water.  The 
North  Branch  of  Two  Rivers  supplies  the. water  used  here,  which  is  healthful,  but 
very  hard.  A  mile  west  of  Northcote  a  salt  spring  issues  in  the  bed  of  this  stream. 
Salt  springs  also  occur  in  the  channel  of  the  South  Branch  of  Two  Rivers,  about  5 
miles  west  of  Hallock. 

Humboldt. — The  section  of  the  deep  artesian  well  on  the  farm  of  D.  H.  Valentine, 
at  this  station,  has  been  given  on  page  75,  and  an  analysis  of  its  water  on  page  537. 
This  water  has  never  been  utilized. 

8t.  Vincent. — A  well  l(i5  feet  deep  was  bored  by  the  railway  company  about  three- 
fourths  of  a  mile  east  of  St.  Vincent  in  the  winter  of  1878-79.  It  yielded  very  saline 
water,  not  used,  which  rose  10  feet  above  the  surface.  The  section  was  alluvial  clay 
and  till  to  the  depth  of  120  feet,  and  gravel  and  sand  thence  to  the  bottom,  45  feet. 

The  common  wells  of  this  county  are  10  to  30  feet  deep,  generally  obtaining  water 
which  is  slightly  alkaline,  but  may  be  used  for  all  farm  and  domestic  purposes,  if  the 
wells  are  drawn  from  plentifully  so  as  to  insure  new  inflow  every  day. 

WELLS    ON    THE    AREA    OF    LAKE    AGASSIZ    IN    NORTH    DAKOTA. 

RICHLAND   COUNTY. 

Walqyeton. — No  artesian  water  was  found  in  a  boring  120  feet  deep  at  the  Rich- 
land County  court-house,  the  section  being  till,  which  incloses  thin  layers  of  sand  and 
gravel.  A  deeper  boring  passed  through  the  drift  to  Cretaceous  shale,  probably  the 
Fort  Benton  formation,  at  19.")  feet. 

The  city  is  furnished  with  water  by  a  system  of  waterworks,  which  pumps  its 
supply  from  the  Red  River,  above  Breckenridge,  at  the  upper  end  of  a  long  ox-bow  or 
horseshoe-like  circuit  of  the  river. 

Fifteen  or  more  flowing  wells  are  reported  in  the  German  settlement  along  the 
Wild  Rice  River,  within  10  miles  southwest  of  Wahpetou,  ranging  in  depth  from  70 
feet  to  305  feet. 

Farmington. — A.  D.  Ellsworth,  1  mile  southwest  of  Farmington  station :  Flowing 
well,  93  feet  deep,  almost  wholly  in  till;  water  of  good  quality,  called  "soft,"  rises  7 


566  THE  GLACIAL  LAKE  AGASSIZ. 

feet  above  the  siirface.  There  are  several  other  flowing  wells  of  similar  depth  in 
this  vicinity. 

Fairview. — On  the  Fairview  Farm  an  artesian  well  240  feet  deep,  bored  wholly 
in  alluvial,  lacustrine,  and  drift  deposits,  has  a  powerful  flow. 

Mooreton. — Artesian  wells  at  the  Mooreton  Eoller  Mills  and  at  the  Central  Hotel 
are  about  135  feet  deep,  obtaining  moderate  flows  of  good  water,  about  4  gallons  per 
minute  from  an  inch  pipe. 

On  the  Minneapolis  Farm,  owned  by  Bull  &  Menage,  about  2  miles  northwest  of 
Mooreton,  a  well  150  feet  deep  flows  7  gallons  per  minute  from  a  three-fourths  inch 
pipe.  At  11  feet  above  the  surface  it  shows  no  perceptible  decrease  in  the  force  of 
the  flow. 

The  Antelope  Farm,  owned  by  Hugh  Moore,  about  3  miles  farther  northwest,  has 
an  artesian  well  173  feet  deeii,  with  two-thirds  as  strong  flow  as  the  last. 

Wyndmere. — The  Northern  Pacific  Elevator  Company  bored  to  the  depth  of 
267  feet,  obtaining  no  artesian  water.  The  thickness  of  the  alluvial,  lacustrine,  and 
drift  formations  was  in  total  218  feet,  below  which  the  boring  went  49  feet  in  dark 
Cretaceous  shale. 

Bwight. — Ten  artesian  wells,  from  85  to  105  feet  deep,  are  within  a  radius  of  5 
miles  around  this  village.  Their  water  is  good,  not  at  all  saline,  but  slightly  alkaline, 
though  less  so  than  that  of  the  common  wells,  which  are  10  to  25  feet  deep. 

Golfax. — H.  E.  Crandall,  Headquarters  Hotel:  Artesian  well,  85  feet  deep;  soil 
and  delta  sand,  0  feet ;  till,  79  feet,  to  sand  and  gravel  at  the  bottom. 

Depths  of  other  artesian  wells  in  Colfax  village,  all  obtaining  good  water  in  the 
drift,  are  as  follows:  At  Cargill  Bros.'  elevator,  125  feet;  at  the  Eed  River  Valley 
mill,  128  feet;  and  at  the  railway  tank,  135  feet. 

Two  flowing  wells,  55  and  CO  feet  deep,  are  reported  within  a  few  miles  east  of 
this  village. 

Walcott. — Minnesota  and  Dakota  Elevator  Company :  Flowing  well,  120  feet  deep ; 
the  water,  which  is  of  excellent  quality,  rises  only  1  foot  above  the  surface. 

The  artesian  town  well,  25  rods  east  of  the  preceding,  is  110  feet  deep.  It  ceases 
flowing  when  the  larger  pipe  of  the  elevator  well,  4  inches  in  diameter,  is  opened  to 
its  full  size. 

An  artesian  well  1  mile  nortli  of  Walcott,  227  feet  deep,  obtains  good  water, 
called  "soft,"  which  rises  only  to  the  surface.  About  2  miles  farther  north  a  well 
104  feet  deep  flows  about  50  barrels  daily,  rising  5  feet  above  the  surface.  Another 
flowing  well,  2  miles  north  of  the  last,  is  131  feet  deep. 

Common  wells  in  all  this  regiou  obtain  ample  supplies  of  water  at  depths  ranging 
from  10  to  30  feet,  and  no  salt  taste  is  noticeable  in  the  water  of  either  the  common 
or  the  artesian  wells. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  567 

CASS   COUNTY. 

Kindred. — No  artesian  wells.  The  common  wells  are  10  to  15  feet  deep,  in  fine 
loamy  silt,  obtaining  slightly  alkaline  water  from  a  layer  of  sand  1  foot  thick  at  the 
bottom. 

Davenimrt. — The  town  well  is  70  feet  deep,  in  alluvial  and  lacustrine  beds,  and 
has  about  10  feet  depth  of  water.  Several  other  wells  in  this  village  are  similar; 
none  artesian. 

Leonard. — Wells  here,  on  tlie  Sheyenne  delta  of  Lake  Agassiz,  obtain  a  copious 
supply  of  excellent  water  at  18  to  20  feet.  The  section  is  all  sand,  which  continues 
beyond  the  depth  of  the  well  bored  or  driven  40  feet  by  the  Northern  Pacific  Elevator 
Company. 

Warren. — At  the  buildings  of  the  Leech  Bros.'  farm,  in  the  southeast  quarter  of 
section  17,  a  boring  47.5  feet  deep,  finding  no  artesian  water,  went  through  the  lacus- 
trine clay,  till,  and  probably  a  considerable  thickness  of  Cretaceous  shale;  and  its 
lowest  75  feet  were  in  a  fine  white  sandstone,  very  hard  and  compact,  doubtless  the 
Dakota  sandstone,  which  here,  as  occasionally  farther  north,  is  so  close  grained  in  its 
upper  portion  as  to  be  almost  impervious  to  water. 

Durhin. — Oargill  Bros.'  elevator:  Artesian  well,  160  feet;  water  chalybeate,  at 
first  a  copious  flow,  diminished  later  by  sand  filling  the  lower  j)art  of  the  pipe. 

Common  wells  in  this  village  and  its  vicinity  are  about  30  feet  deep. 

Everest. — At  the  Cargill  Bros.'  'elevator  a  well  100  feet  deej)  derives  water  from 
gravel  at  the  oottom,  rising  nearly  to  the  surface.  The  common  wells  are  40  to  50  feet 
deep,  with  good  water  from  gravel,  filling  the  wells  to  the  depth  of  20  to  30  feet. 

QUI. — An  artesian  well  on  the  farm  of  .J.  0.  Gill,  in  the  northwest  quarter  of 
section  35,  is  about  260  feet  deep,  with  water  rising  15  feet  or  more  above  the  surface. 

Fargo. — The  alluvial  and  lacustrine  beds  and  the  glacial  drift  are  together  220 
feet  thick,  being,  in  descending  order,  stratified  clay,  95  feet;  sand  and  gravel,  10  feet, 
yielding  water  which  rises  nearly  to  the  surface:  and  till,  115  feet,  inclosing  occasional 
layers  and  veins  of  water-bearing  sand  and  gravel.  Below  the  drift  a  boring  went 
42  feet  farther,  probably  in  Cretaceous  strata  referable  to  the  Fort  Benton  formation, 
being  soft,  dark  blue  shale,  32  feet;  coarse  sand  rock,  6  feet;  and  a  second  shale,  4 
feet,  in  which  the  boring  stopped  at  a  total  depth  of  262  feet.  Water  rose  from  the 
sand  rock  to  10  or  12  feet  below  the  surface,  apparently  a  good  supply.' 

Pillsbury  &  Hulbert  elevator:  Well,  150  feet;  water  rises  to  8  feet  below  the 
surface,  in  so  copious  supply  that  it  can  not  be  lowered  by  pumping;  it  is  of  excellent 
quality,  softer  than  the  water  of  the  rivor. 

Most  of  the  water  used  throughout  the  city  is  taken  from  the  river  by  a  system 
of  waterworks. 

'  U.  S.  Geol.  Survey  of  the  Territories,  1872,  p.  301. 


568  THE  GLACIAL  LAKE  AGASSIZ, 

Mapleton. — Wells  in  this  village  are  60  to  80  feet  deep,  in  alluvial  and  lacustrine 
clayey  silt,  obtaining  slightly  alkaline  water  from  sandy  beds  at  the  bottom,  whence 
it  rises  to  be  30  to  40  feet  deep. 

Dalrymple. — Cass  &  Cheeney  Elevator  Company:  Well,  60  feet;  water  seeps, 
scanty,  alkaline. 

Casselton. — The  city  artesian  well  is  327  feet  deep,  its  section  being  yellowish 
alluvial  clay,  25  feet;  darker  bluish  clay  and  sand,  alluvial  and  lacustrine,  45  feet; 
till,  180  feet,  inclosing  thin  seams  and  veins  of  sand  and  gravel ;  aiid  very  fine-grained 
sandstone,  probably  the  Dakota  sandstone,  in  some  portions  containing  fragments  of 
lignite,  77  feet,  in  which  the  boring  ceased.  The  same  section,  to  the  depth  of  317 
feet,  was  also  found  by  the  well  at  Capt.  0.  May's  flouring  mill.  Both  these  wells 
obtain  slightly  brackish  water,  which  rises  40  feet  above  the  surface. 

Smith  Stemmel,  3  miles  west  of  Casselton,  has  a  similar  flowing  well  about  350 
feet  deep. 

Northern  Pacific  Elevator  Company:  Well,  100  feet;  water,  somewhat  saline, 
rises  from  a  layer  of  sand  to  6  feet  below  the  surface. 

The  common  wells  of  Casselton  and  its  vicinity  vary  in  depth  from  20  to  70  feet, 
the  deepest  obtaining  good  water  at  the  top  of  the  till,  whence  it  usually  rises  to  fill 
the  lower  half  of  the  well. 

Wheatland. — Slightly  alkaline  water  is  supplied  by  most  of  the  wells  in  the 
village,  which  are  20  to  30  feet  deep  in  till;  but  water  of  excellent  quality  is  obtained 
on  the  Campbell  beach,  in  the  east  edge  of  the  village,  by  wells  15  to  20  feet  deep  in 
the  beach  gravel  and  sand. 

Tower  City. — The  city  artesian  well  has  been  described  on  page  535. 

Reed. — C.  H.  Welton,  southeast  quarter  of  section  17:  Flowing  well,  153  feet 
deep,  in  alluvial  and  lacustrine  deposits  for  its  upper  part,  with  much  till  below. 
Water,  fresh,  and  soft  enough  for  washing  with  soap,  rises  4  feet  above  the  surface. 

B.  P.  Reynolds,  northeast  quarter  of  section  20,  about  40  rods  southeast  from 
the  last:  Well,  similarly  flowing,  only  130  feet  deep.  Probably  these  two  wells  are 
supplied  by  separate  water-bearing  layers. 

Baymond. — E.  Porrett,  southwest  quarter  of  section  6:  Well,  80  feet,  in  alluvial 
clay  and  till,  the  latter  containing  fragments  of  lignite;  the  water,  somewhat  alkaline, 
rises  to  1  foot  below  the  surface. 

H.  G.  Roberts,  in  the  northeast  quarter  of  section  23,  close  north  of  the  Maple 
River,  has  a  flowing  well  190  feet  deep. 

Harwood. — Minneapolis  and  Northern  Elevator  Company:  Flowing  well,  117  feet 
deep;  water  rises  from  sand  and  gravel  to  10  feet  above  the  surface;  it  is  fresh,  good 
for  drinking,  and  called  "soft"  for  washing. 

Arf/usinlle. — The  Minneapolis  and  Northern  Elevator  Company  has  three  arte- 
sian wells,  one  158  feet  deep;  another,  20  feet  distant,  157  feet;  and  a  third,  about  35 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  569 

rods  distant,  147  feet.  Below  a  small  depth  of  alluvial  and  lacustrine  clay  these  go 
through  till  with  bowlders.  The  water,  very  good  for  drinking,  comes  from  a  bed  of 
gravel  and  sand  5  to  7  feet  thick,  which  was  passed  through  to  till  beneath  in  one 
of  these  wells. 

Berlin. — Two  flowing  wells  in  the  northeastern  part  of  this  township  are  87  feet 
and  about  100  feet  deep.  The  common  wells  are  40  to  00  feet  deep,  with  water  rising 
to  10  or  15  feet  below  the  surface. 

Amenia.— The  artesian  well  at  the  elevator  of  the  Amenia  and  Sharon  Land 
Company  is  279  feet  deep ;  water  rises  5  feet  above  the  surface,  not  a  copious  flow. 
Another  boring  went  to  the  depth  of  400  feet,  finding  no  lower  artesian  water.  The 
section  was  soil,  2  feet;  yellowish  gray  till,  .'50  feet;  harder  dark  bluish  till,  about  200 
feet,  inclosing  occasional  water-bearing  layers  of  sand  and  gravel ;  and  Cretaceous 
beds  below,  the  last  100  feet  or  more  being  very  fine-grained  white  sandstone  and 
nearly  white  shale,  probably  the  Dakota  formation. 

Edward  McNeill,  a  half  mile  east  of  Amenia,  has  an  artesian  well  215  feet  deep, 
yielding  a  large  supply  of  water.  On  Lee  E.  Clark's  farm,  some  4  miles  distant  to 
the  northeast,  the  copiously  flowing  water  of  a  well  about  275  feet  deep  rises  30  feet 
above  the  surface.  All  these  deep  wells  at  and  near  Amenia  have  slightly  brackish, 
haid  water. 

William  Hinkle  Smith,  in  section  32,  has  bored  290  feet,  obtaining  no  artesian 
water.  The  well  most  used  by  this  large  farm  is  75  feet  deep,  with  a  very  abundant 
supply  of  good  water,  which  rises  to  20  feet  below  the  surface. 

On  the  farm  of  Gage  &  Davis,  in  the  southeast  quarter  of  section  9,  a  well  155 
feet  deep  has  water  which  rises  from  the  bottom  to  5  feet  below  the  surface.  This 
water,  like  that  of  Mr.  Boustead's  well,  noted  on  page  553,  contains  gas  which  is  not 
visible  when  the  water  first  flows  from  the  pump,  but  shows  in  very  minute  bubbles, 
as  flue  as  dust,  from  one-fourth  to  three-fourths  of  a  minute  later,  then  disappearing 
so  that  the  water  is  left  clear.  It  is  called  excellent  water  for  drinking  and  for  engine 
boilers. 

Eipon. — A  railway  boring  to  the  depth  of  280  feet  found  no  artesian  water. 
Common  wells  mostly  are  20  to  40  feet  deep,  obtaining  a  copious  supply  from  sand 
and  gravel  beds  inclosed  in  the  till. 

Gardner. — Minneapolis  and  Northern  Elevator  Company:  Well,  125  feet;  water 
rises  12  feet  above  the  surface. 

S.  C.  Dalrymxjle,  section  C:  Artesian  well  about  230  feet  deep;  strong  flow. 
There  are  ten  or  more  other  flowing  wells  within  a  few  miles  around  Gardner,  ranging 
from  96  feet  to  2.50  feet  in  depth.    Their  water  is  slightly  brackish. 

Grandin. — The  village  of  Grandiu  has  four  artesian  wells  within  an  extreme 
distance  of  50  rods  from  east  to  west  and  half  as  much  from  south  to  north,  as  fol- 
lows: William  Black,  105  feet  deep,  with  water  at  first  rising  12  feet,  now  8  feet;  the 


570  THE  GLACIAL  LAKE  AGASSIZ. 

Grandin  Hotel,  P.  C.  Weisbecker,  158  feet,  water  rising  15  feet;  the  Minneapolis  and 
Northern  Elevator  Company,  1S7  feet,  water  rising  113  feet;  and  J.  W.  Thorn,  at  his 
store,  248  feet,  water  rising  only  2  feet.  All  these  wells  are  slightly  saline,  bnt  are 
called  good  for  drinking  and  cooking,  except  iu  making  tea.  It  is  remarkable  that 
they  obtain  water  at  fonr  distinct  levels,  showing  that  at  least  the  upper  water- 
bearing deposits  of  gravel  and  sand  are  narrow  veins,  as  of  stream  courses;  or,  if 
they  form  broad  sheets,  those  above  are  pinched  ovit  in  places,  so  that  the  deposits  of 
overlying  and  underlying  till  come  together.     (Bee  pages  525,  526.) 

TUAILL   COUNTY. 

Mm  River. — Robert  Young,  about  a  mile  west  of  Quincy,  has  an  artesiau  well 
213  feet  deep ;  water  copious,  slightly  saline. 

Alexander  Armstrong's  well,  a  half  mile  south  of  Mr.  Young's,  is  110  feet  deep, 
with  very  strong  How,  having  scarcely  any  perce])tible  saline  taste. 

Kelso. — St.  Anthony  and  Dakota  Elevator  Comjjauy:  Well,  110  feet;  mostly  in 
till,  below  a  considerable  thickness  of  alluvial  and  lacustrine  clay;  water  at  first 
overflowed,  but  now  stands  a  few  feet  below  the  surface;  it  is  capable  of  supplying 
200  barrels  in  twelve  hours,  the  diameter  of  the  pipe  being  2  inches. 

Minneaiiolis  and  Northern  Elevator  Company:  Well,  109  feet;  water  overflows 
slightly:  ample  supply  for  pumjiing.  The  water  of  both  these  wells  is  slightly  salty, 
but  is  not  harmful  for  drinking;  it  rapidly  rusts  through  the  plate  of  engine  boilers 
iu  which  it  is  used. 

James  Johnson,  section  3:  Artesian  well,  175  feet  deep;  the  water  flows  from 
the  pipe,  which  is  2  inches  in  diameter,  at  the  rate  of  about  2  barrels  per  minute, 
forming  a  considerable  brook ;  when  confined  in  the  pipe,  it  rose  20  feet  above  the 
surface,  and  flowed  with  little  apparent  diminution.  The  water  is  saline,  but  both 
cattle  and  people  prefer  it  rather  than  the  water  of  the  adjoining  creek,  the  North 
Branch  of  the  Elm  Eiver.  This  well  was  bored  only  about  150  feet  deep,  the  section 
having  been  nearly  all  till;  then,  within  fifteen  or  twenty  minutes,  the  pipe  sank 
about  20  feet  in  quicksand,  and  it  settled  more  during  the  following  night.  When 
the  sand  filling  the  lower  part  of  the  pipe  was  cleared  out,  the  water  rose  with  such 
force  as  to  bring  up  gravel  stones  from  1  to  IJ  inches  in  diameter  in  the  2inch  pipe, 
showing  that  it  had  sunk  to  a  bed  of  gravel.  In  this  well  a  feeble  artesian  flow  was 
noted  at  about  110  feet,  as  in  the  wells  of  Kelso  village,  li  miles  distant.  There  are 
several  other  flowing  wells  within  1  or  2  miles  around  Mr.  Johnson's,  some  being 
about  110  feet  deep,  and  others  having  nearly  the  same  depth  as  his  well. 

S.  A.  Dalrymple,  southeast  corner  of  section  1:  Artesian  well,  180  feet  deep; 
2-inch  pipe,  flowing  a  stream  a  half  inch  iu  diameter  at  3  feet  above  the  surface; 
water  slightly  brackish. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  571 

Alexander  Smart,  southeast  quarter  of  section  12:  Boring  417  feet  deep,  obtain- 
ing no  artesian  water;  the  alhivial  and  lacustrine  beds  of  the  surface  have  an 
undetermined  thickness,  probably  less  than  GO  feet;  next  below,  till  extends  about 
250  feet,  inclosing  occasional  thin  beds  of  sand  and  gravel,  to  the  base  of  the  drift 
at  310  feet.  Thence  the  boring  went  107  feet  in  a  very  fine-grained  white  sandstone, 
in  part  very  hard,  but  in  other  parts  less  so  than  the  till.  The  drillings  from  this 
formation,  believed  to  be  the  Dakota  sandstone,  are  mostly  similar  to  flour  in  their 
fineness,  but  usually  they  also  contain  many  small,  rounded  quartz  grains,  from  a 
hundredth  to  a  fiftieth  of  an  inch  in  diameter, 

Bohnsacl: — K.  M.  Cunningham,  southeast  quarter  of  section  5,  township  144, 
range  .52 :  Well,  140  feet  deep,  wholly  in  till ;  water  rises  from  sand  and  gravel  at  the 
bottom  to  30  feet  below  the  surface. 

Hague. — On  Farm  No.  1  of  the  Grandin  and  Dalrymple  Farming  Company,  at 
Hague  post-office,  northwest  quarter  of  section  2.5,  township  145,  range  49,  are  two 
artesian  wells,  ICO  feet  and  210  feet  deep ;  water,  slightly  saline,  rises  from  each  to  a 
height  of  10  feet  or  more  above  the  surface.  The  well  on  Farm  No.  3,  in  the  northeast 
quarter  of  section  9,  township  144,  range  49  (Elm  liiver),  is  ICO  feet  deep,  with  water 
rising  just  to  the  surface.  From  another  artesian  well,  on  Farm  No.  C,  in  the  south- 
east quarter  of  section  33,  township  145,  range  49,  also  IGO  feet  deep,  the  water 
rises  6  feet. 

Hillsboi'o. — In  the  city  of  Hillsboro  and  within  a  distance  of  5  miles  there  are 
probably  thirty  or  more  artesian  wells,  mostly  between  100  and  200  feet  dee]),  all 
obtaining  somewhat  saline  and  alkaline  water.  Notes  of  several  in  Hillsboro  are  as 
follows : 

W.  H.  York,  in  the  northeast  part  of  the  city:  105  feet  deep;  flow  about  200 
barrels  daily;  water  slightly  brackish,  softer  than  the  water  of  the  deeper  wells. 

City  well,  at  the  intersection  of  the  two  i^rincipal  streets:  185  feet  deep;  flow 
about  75  barrels  daily,  through  C-iuch  pipe;  strongly  brackish,  used  only  for  watering 
horses  aiid  cattle. 

S.  C.  Sherwood,  in  the  north  part  of  the  city:  About  190  feet  deep;  flow  esti- 
mated at  400  barrels  daily,  through  2-inch  pipe.  The  water  of  this  well,  with  largest 
flow  in  the  town,  though  salty,  is  employed  for  all  uses  of  the  house  aud  stable, 
including  drinking  and  cooking.  But  in  general  throughout  the  city  the  principal 
supply  for  domestic  uses  is  taken  from  the  Goose  Eiver. 

Minneapolis  and  Northern  Elevator  Company :  195  feet  deep. 

J.  E.  Nunn's  livery  stable:  198  fee^  deej). 

Florence  Mill  Company :  195  feet  deep ;  flow,  250  barrels  daily. 

At  the  North  Dakota  Roller  Mill,  in  the  south  part  of  the  city,  several  borings 
have  been  made,  in  all  of  which  combustible  gas  has  been  found  at  the  depth  of  105 
to  120  feet.    The  deej)est  of  these  borings  went  G30  feet,  obtaining  no  artesian  water. 


572  THE  GLACIAL  LAKE  AGASSIZ. 

A  considerable  thickness  of  Cretaceous  beds,  apparently  the  Fort  Benton  shales  and 
the  Dakota  sandstone,  were  penetrated,  reaching  "quartzite"  at  020  feet. 

Blanchard. — Again,  probably  as  many  as  thirty  artesian  wells  exist  in  Blanchard 
Tillage  and  within  a  radius  of  5  miles  around,  varying  in  their  depth  from  150  to  404 
feet.  The  glacial  drift  extends  to  a  depth  of  about  200  feet,  below  which  these  wells 
pass  into  Cretaceous  shale  and  very  fine-grained  sandstone,  pi'obably  the  Dakota 
formation.     The  following  are  two  of  the  deepest  borings: 

S.  S.  Blanchard,  section  11,  township  145,  range  52:  Well,  375  feet:  brackish 
water,  good  for  stock  throughout  the  year  and  used  in  engine  boilers,  rises  15  feet 
above  the  surface. 

Emerson  &  Wild,  southwest  quarter  of  section  19,  township  145,  range  51,  a 
half  mile  north  of  Blanchard  Village:  Well,  404  feet  deep;  brackish  water,  capable 
of  rising  40  feet  or  more  above  the  surface,  flows  at  the  rate  of  -iO  gallons  per  minute 
from  a  2i-inch  pipe. 

Norman. — On  Jones  &  Brinker's  farm,  in  section  13,  an  artesian  well  about  350 
feet  deep  has  a  strong  flow  of  saline  water. 

Mayville.— Goose  Eiver  Mill,  owned  by  Gibbs  &  Edwards:  Artesian  well,  395 
feet  deep,  in  drift  about  200  feet  and  below  in  Cretaceous  shale  and  sandstone;  water 
brackish. 

The  city  artesian  well,  .355  feet  deep,  has  a  strong  flow  of  brackish  water,  which 
rises  22  feet  above  the  surface,  its  rate  of  flow  being  about  85  gallons  per  minute. 

Common  wells  in  Mayville  and  its  vicinity  are  20  to  40  feet  deep,  in  alluvial  clayey 
silt  and  till,  obtaining  somewhat  alkaline  water.  The  supply  needed  for  drinking  and 
cooking  is  taken  from  the  Goose  Eiver,  excepting  by  those  who  have  rain-water 
cisterns. 

Portland. — A  boring  for  the  railway  tank  is  said  to  have  gone  to  the  depth  of 
275  feet,  obtaining  no  artesian  water. 

Minnesota  and  Dakota  Elevator  Company :  Well,  90  feet;  water  rises  to  20  feet 
below  the  surface;  it  is  brackish,  and  forms  much  scale  on  the  boilers  of  eugmes. 

The  common  wells  in  Portland  are  15  to  40  feet  deep  in  till,  from  which  water 
seeps,  somewhat  alkaline. 

Hatton.—Gsirgin  Bros.'  elevator:  Well,  254  feet;  delta  silt,  about  20  feet;  till, 
inclosing  occasional  sand  and  gravel  layers,  about  200  feet;  and  sand,  34  feet.  Excel 
lent  water,  which  makes  but  little  scale  on  the  engine  boilers,  rises  to  6  feet  below  the 
surface. 

Common  wells  here  are  oo^y  10  to  12  feet  deep,  obtaining  plentiful  and  good 
water  in  the  fine  sand  of  the  Elk  Valley  delta. 

About  3  miles  southwest  of  Hatton,  in  section  25,  Newburg,  Steele  County,  a 
boring  on  the  farm  of  Smith  &  Mills  went  to  the  depth  of  .553  feet,  obtaining  a  strong 
artesian  flow,  which,  however,  soon  ceased  because  the  lower  part  of  the  pipe  became 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  573 

filled  with  sand.  The  bottom  of  this  boring  is  at  nearly  the  same  elevation  above  the 
sea  as  that  of  the  deep  artesian  wells  of  Blanchard  and  Mayville,  being,  like  them, 
doubtless,  in  the  Dakota  sandstone. 

GRAND   FORKS   COUNTY. 

Northwood. — Eed  River  Valley  Elevator  Company:  Well,  20  feet  deep,  in  delta 
sand;  water  usually  10  to  15  feet  deep,  overflowing  in  the  spring.  Common  wells 
here  are  15  to  IS  feet  deep,  supplying  good  water,  which  forms  little  scale  on  engine 
boilers. 

Kempton. — Wells  in  the  vicinity  of  Kempton  are  about  20  feet  deep,  the  section 
being  soil,  2  feet;  fine  clayey  sand,  10  feet;  a  harder  bed  of  sand,  2  feet;  and  quick- 
sand below,  which  contains  an  ample  supply  of  excellent  water. 

Grand  Forks.— A  railway  well  bored  near  the  depot  in  1881  to  the  depth  of  265 
feet,  5  inches  in  diameter,  reduced  below  to  3h  inches,  yielded  in  August  of  that  year, 
probably  after  the  lower  part  of  the  pipe  had  become  filled  with  sand,  only  a  very 
scanty  overflow;  water  saline,  not  used. 

C.  J.  Alloway,  in  the  north  edge  of  the  city:  Artesian  well,  270  feet;  alluvial 
and  lacustrine  clay,  30  feet;  till,  inclosing  occasional  beds  of  sand  and  gravel,  220  feet; 
and  sand,  20  feet;  the  water,  too  saline  to  be  used,  rises  2  feet  above  the  surface. 

The  common  wells  of  Grand  Forks,  20  to  30  feet  deep,  have  water  of  fair  quality, 
but  the  city  is  mainly  supplied  through  waterworks  which  pump  irom  the  river. 

Brenna. — Lawrence  Kennedy,  in  the  north  part  of  this  township,  about  halfway 
between  Grand  Forks  and  Ojata,  has  a  flowing  well  of  brackish  water  90  feet  deep. 

Ojata. — Minneapolis  and  Northern  Elevator  Company:  Flowing  well,  115  feet 
deep;  water  saline,  unfit  for  engine  boilers,  though  it  has  been  so  used.  Similar 
artesian  water  was  also  found  by  this  well  at  the  depth  of  about  70  feet.  Common 
wells  are  mostly  15  to  18  feet  deep,  obtaining  water  that  is  slightly  alkaline,  though 
not  perceptibly  so  to  the  taste.     When  dug  deeper  they  get  bitter  or  salty  water. 

JEmerado. — Wells  in  this  village  and  its  vicinity  are  15  to  20  feet  deep,  in  till,  with 
thin  veins  and  layers  of  sand ;  good  water.  One  well,  bored  70  feet  deep,  near  the 
depot,  found  no  water  supply,  while  another  well  10  rods  east  found  plenty  of  water 
at  20  feet. 

The  well  of  the  railway  tank  was  dug  53  feet  deep  in  a  dry  season,  and  the  work- 
men at  night  left  their  tools  at  the  bottom,  which  gave  no  sign  of  water;  but  the  next 
morning  it  was  full  of  w^ater  to  8  feet  below  the  surface. 

Arvilla. — Common  wells  at  and  near  Arvilla  are  15  to  30  feet  deep,  in  till,  obtaiu- 
ing  somewhat  alkaline  water.  The  first  boring  for  a  town  well  went  nearly  200  feet 
in  the  till,  obtaining  no  sufficient  water  supply.  A  second  boring  found  abundance 
of  good  water  at  85  feet,  whence  it  rises  to  about  30  feet  below  the  surface  and  is  not 
lowered  by  vigorous  pumping. 


574  THE  GLACIAL  LAKE  AGASSIZ. 

Larimore. — The  well  at  the  Shermau  House,  60  feet  deep  in  tbe  fine  silt  and  sand 
of  tbe  Elk  Valley  delta,  and  other  shallower  wells,  are  noted  on  pages  334,  335.  The 
water  is  copious  and  of  good  quality,  forming  little  scale  on  engine  boilers. 

Manvel. — Joseph  Oolosky,  Manvel  Hotel :  Artesian  well,  166  feet  deep,  in  alluvial 
and  lacustrine  silt  and  till,  inclosing  occasional  layers  of  sand  and  fine  gravel.  A 
large  flow  of  saline  water  was  found  in  such  a  layer  at  107  feet.  The  second  flow,  at 
166  feet,  is  very  strong,  running  from  the  2-inch  pipe  at  the  rate  of  about  40  gallons 
per  minute. 

Minneapolis  and  Northern  Elevator  Company :  Artesian  well,  175  feet;  the  water 
is  capable  of  rising  more  than  45  feet  above  the  surface,  there  flowing  from  an  inch 
pipe  (reduced  from  the  diameter  of  the  well,  which  is  2  inches)  at  the  rate  of  about 
6  gallons  per  minute.  In  1887  this  well  had  been  running  five  years  and  showed  no 
diminution  of  flow.  The  water  contains  much  sulphate  of  magnesia,  not  being  so  salt 
as  that  at  107  feet.  In  engine  boilers  it  forms  a  powdery  i>recipitate,  which  is  easily 
blown  out  by  the  engineer,  not  being  so  troublesome  as  the  usual  scale. 

Turtle  River. — Richard  Forrest,  northeast  quarter  of  section  28 :  A  boring,  seen 
when  it  was  in  progress  at  150  feet,  had  brackish  artesian  water  flowing  feebly  from 
sand  all  the  way  below  100  feet. 

Johnstown. — William  Stratton,  section  22 :  Well  in  alluvial  clay,  which  at  the  depth 
of  19  feet  contained  a  log  10  inches  in  diameter,  thought  to  be  birch.  It  was  chopped 
off  to  permit  the  well  to  go  deeiier.  Another  well  in  the  southwest  part  of  this  town- 
ship found  two  similar  tree  trunks  16  feet  below  the  surface. 

WALSH   COUNTY. 

Ardoch. — Minneapolis  and  Northern  Elevator  Company :  Artesian  well,  164  feet, 
the  section  being  mostly  till;  large  flow  of  saline  water. 

Brooks  Bros.'  elevator:  Well,  42  feet  deep,  8  feet  in  diameter,  with  plenty  of 
water.  A  boring  below  this  to  the  total  depth  of  100  feet  from  the  surface  was  stopped 
by  a  bowlder.  The  section  was  alluvial  clay,  15  feet;  sand  and  gravel,  ^  foot;  and 
till,  easy  to  dig  and  bore,  85  feet.  Alkaline  water  seeps,  much  coming  from  the  gravel 
at  15  feet. 

Common  wells  at  Ardoch  are  15  to  20  feet  deep,  most  of  them  obtaining  tolerably 
good  water.  The  town  has  two  jmblic  wells  or  cisterns,  each  13  feet  deep  and  13  feet 
in  diameter,  and  another  measui'ing  15  feet  in  these  dimensions,  for  fire  protection. 

Minto. — Minneapolis  and  Northern  Elevator  Company:  Artesian  well,  200  feet 
deep;  alluvial,  lacustrine,  and  drift  deposits,  190  feet,  the  lower  two-thirds  being  till, 
with  no  important  water-bearing  veins  or  layers ;  then  sand  and  gravel,  10  feet  and 
extending  below.  The  water  rushed  up  with  such  force  as  to  bring  pebbles  an  inch 
in  diameter,  and  rises  when  confined  in  pipes  to  a  height  of  60  feet  above  the  surface. 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  575 

It  is  quite  brackish,  but  some  persous  have  druuk  it  freely  aud  almost  solely  during 
several  years,  thinkiug  it  favorable  for  their  health. 

Brooks  Bros.'  elevator:  Well,  196  feet  deep,  with  similar  strong  flow  as  the 
foregoing. 

The  common  wells  are  15  to  20  feet  deep,  in  yellow  alluvial  clay,  to  blue  clay 
which  is  not  dug  into;  water  seeping,  slightly  alkaline. 

Grafton. — The  dee])  artesian  well  of  the  city,  passing  through  Lower  SUurian 
strata  below  the  drift,  and  obtaining  a  powerful  flow  of  brackish  water,  has  been 
described  on  jiages  77,  78. 

The  Minneapolis  and  Northern  Elevator  Company  and  the  Brooks  Bros.'  elevator 
had  artesian  wells,  each  156  feet  deep,  but  their  water  was  so  saline  aud  scanty  that 
they  are  disused. 

The  water  of  the  common  wells  here,  12  to  25  feet  deep,  is  slightly  alkaline,  but 
is  considered  healthful. 

About  5  miles  northeast  of  Grafton  a  well  is  reported  to  have  found  in  the 
alluvial  clay,  at  the  depth  of  35  feet,  a  log  about  a  foot  in  diameter,  which  was  chopped 
off  at  both  sides  of  the  well. 

Conway. — The  depths  of  the  common  wells  range  from  20  to  60  feet,  in  till. 

Park  River. — Wells  15  to  40  feet  deep,  in  till,  obtaining  a  ijlentiful  supply  of 
good  water. 

■    PEMBINA   COUNTY. 

8t.  Thomas. — Minneapolis  and  Northern  Elevator  Company:  Artesian  well,  175 
feet  deep,  mostly  in  till;  water  saline,  but  used  in  the  engine  boiler.  The  Brooks 
Bros.'  elevator  is  supplied  by  a  well  only  18  feet  deep. 

The  common  wells  are  15  to  20  feet  deep,  in  alluvial  clay;  water  slightly  alkaline. 

Glasston. — The  Minneapolis  and  Northern  Elevator  Company  has  a  flowing  well 
about  200  feet  deep,  with  water  rising  only  2  feet  above  the  surface,  but  yielding  an 
inexhaustible  supply  when  pumped.  It  is  brackish,  but  is  druuk  freely  by  stock  and 
by  some  people,  who  soon  like  it,  and  no  injurious  ettects  attend  its  use. 

Common  wells,  mostly  14  to  20  feet  deep,  have  somewhat  alkaline  water.  Several 
other  wells  within  a  few  miles  east  of  the  railway  between  St.  Thomas  and  Glasston, 
and  about  the  latter  station,  go  90  to  150  feet  through  till  to  gravel  and  sand,  from 
which  water,  slightly  brackish,  rises  immediately  to  a  permanent  level  10  to  20  feet 
below  the  surface. 

Hamilton. — Minneapolis  and  Northern  Elevator  Company:  Artesian  well,  179 
feet;  water  brackish. 

Rand  &  Nortou's  livery  stable:  Artesian  well,  175  feet;  also  brackish,  bat  agree- 
ing with  horses  and  cattle. 

The  common  wells  of  Hamilton  are  12  to  20  feet  deep,  usually  having  good 
water.    Many  other  wells  have  been  bored  in  this  vicinity  75  to  150  feet  deep,  only 


576  THE  GLACIAL  LAKE  AGASSIZ. 

rarely  obtaining  artesian  flows;  bnt  ^vater,  found  in  gravel  and  sand  at  the  bottom 
generally  rises  nearly  to  the  surface.  In  some  wells  the  water  is  too  salty  or  bitter  to 
be  used,  but  others  equally  deep  have  fresh  water.  The  former  probably  derive  their 
water  supply  from  great  distances  through  beds  of  sandstone  underlying  the  drift, 
while  the  latter  receive  their  water  from  rains  on  neighboring  areas,  percolating  only 
through  porous  sand  aad  gravel  beds  of  the  drift  sheet. 

Bathgate. — The  artesian  well  of  the  Minneapolis  and  Northern  Elevator  Com- 
pany is  143  feet  deep,  passing  through  alluvial  and  lacustrine  clay  and  till  to  coarse 
sand,  whence  a  very  copious  flow  of  water  rises  to  G  feet  above  the  surface.  It  is 
somewhat  saline  and  alkaline,  but  its  mineral  matter  is  chiefly  deposited  as  a  powdery 
sediment  in  the  boilers  of  engines,  which  can  be  easily  blown  out. 

Dui'ing  the  year  1887  eleven  artesian  wells,  ranging  from  130  to  IGO  feet  in  depth, 
were  bored  within  a  radius  of  5  miles  about  Bathgate. 

There  are  no  shallow  wells  in  this  town,  as  the  seeping  surface  water  is  too 
alkaline.    The  water  of  the  Tongue  River  is  used  for  ordinary  domestic  purposes. 

Neche. — Minneapolis  and  Northern  Elevator  Company:  Well,  aboixt  175  feet 
deep;  water  saline,  rising  to  a  few  feet  below  the  surface;  unfit  for  any  use. 

Alcra. — Abner  Freich,  at  center  of  section  18,  township  IGl,  range  55,  6  rods 
southeast  of  the  Tongue  Eiver:  Well,  dug  at  first  about  16  feet  deep,  having  good 
water,  which  seeped  from  the  alluvial  clay.  In  an  unusually  dry  season  it  was  dug  4 
feet  deeper,  and  found  a  layer  of  sand  from  which  water  of  inferior  quality  soon  rose 
6  feet,  to  the  level  of  the  river. 

WELLS    ON    THE    AREA    OF    LAKE    AGASSIZ    IN    MANITOBA. 

Artesian  or  flowing  wells  are  obtained  at  many  localities  in  Manitoba  near  the 
Ked  River,  as  in  Wiuniijeg  and  southward,  where  water  often  rises  to  the  surface  from 
layers  of  sand  and  gravel  in  the  drift. 

Winnipeg. — About  10  wells  have  been  bored  by  the  city  authorities  of  Winnipeg, 
for  supplying  water  for  domestic  use.  Mr.  H.  N.  Ruttau,  the  city  engineer,  states 
that  about  a  dozen  of  these  wells  go  into  the  bed-rock,  which  is  limestone,  while  the 
others  derive  their  water  from  layers  of  quicksand  in  or  beneath  the  till.  Several  of 
them  in  the  west  part  of  the  city  are  artesian,  but  eastward  the  water  rises  only  to  5 
or  10  feet  below  the  surface.  The  water  is  considered  of  good  (luality  for  drinking 
and  cooking,  but  it  contains  much  mineral  matter  in  solution,  chiefly  the  sulphates  of 
lime  and  magnesia. 

Alluvial  stratified  clay  extends  to  a  depth  that  varies  from  3  to  10  feet  or  more. 
This  is  underlain  by  the  glacial  till  or  bowlder-clay,  which  incloses  thin  veins  and 
layers  of  fine  gravel  and  sand,  and  frequently  is  underlain  by  sand  and  gravel,  but 
in  many  places  extends  to  the  limestone.  The  upper  part  of  the  till  here  shows  an 
imperfect  stratification,  due  to  its  deposition  in  Lake  Agassiz,  and  contains  a  less 


NOTES  OF  ARTESIAN  AND  COMMON  WELLS.  577 

proportion  of  bowlders  and  gravel  than  its  lower  part,  which  is  very  hard,  and  is 
therefore  commonly  denominated  "hardpan."  The  depth  to  the  limestone  varies  from 
30  to  60  feet  in  the  west  part  of  the  city,  and  increases  to  about  75  feet  eastward. 

One  of  these  wells,  bored  in  the  west  edge  of  the  city,  close  north  of  the  Assini- 
boine  and  IJ  miles  west  of  the  Osborne  street  bridge,  went  32  feet  in  stratified  clay 
and  till,  and  then  100  feet  in  limestone,  mostly  of  light  buff  or  cream  color,  obtaining 
water  of  good  quality  at  132  feet,  which  rose  to  5  feet  below  the  surface.  The  bed- 
rock is  nearly  like  that  which  outcrops  at  Lower  Fort  Garry  and  East  Selkirk. 

A  general  section  of  the  superficial  deposits  at  Winnipeg  is  noted  by  J.  Hoyes 
Panton  as  follows,  from  information  supplied  by  Mr.  Piper,  known  as  having  an 
extensive  experience  in  well  boring  throughout  the  city: 

1.  Surface  mold,  1  to  4  feet  thick,  dark  color,  and  exceediugly  fertile. 

2.  "Yellow  gumbo,"  2  to  3  feet;  a  very  sticky  form  of  yellowish  clay,  which  usually  holds  consid- 
erable water. 

3.  Dark  gray  clay,  30  to  50  feet  thick,  with  bowlders  scattered  throughout,  some  of  them  4  feet 
in  diameter  and  chiefly  gneissoid,  and  no  doubt  derived  from  Laurentian  rocks. 

4.  Light-colored  clay,  1  to  3  feet,  containing  many  small  stones. 

5.  Hardpan,  2  to  10  feet,  a  very  solid  and  compact  form  of  clay. 

6.  Sand,  gravel,  and  bowlders,  5  to  25  feet. 

7.  Angular  fragments,  1  to  3  feet,  usually  limestone,  and  largely  derived  from  the  solid  rock  which 
lies  immediately  below  it. 

This  loose  material  is  far  from  being  uniform,  and  varies  so  much  in  its  arrangements  that  scarcely 
any  two  borings  show  the  same  distribution.  Sometimes  there  is  little  or  no  hardpan,  while  in  other 
parts  it  is  several  feet  thick.  However,  as  a  usual  thing,  these  seven  forms  of  strata  are  passed  through 
in  boring,  and  varying  in  thickness  to  the  number  of  feet  already  mentioned. ' 

St.  Boniface. — Wells  in  St.  Boniface  are  nearly  the  same  as  in  Winnipeg,  on  the 
opposite  side  of  the  river.  The  deepest  learned  of  is  on  the  exhibition  ground,  156 
feet  deep,  being  stratified  clay  and  till,  36  feet,  its  lowest  10  feet  very  hard  and  com- 
pact; sand,  44  feet,  to  the  bed-rock  at  80  feet;  then  limestone,  of  light  cream  color  or 
nearly  white,  penetrated  76  feet  and  extending  below. 

Niverville. — Thomas  W.  Craven,  hotel:  Well,  65  feet  deep,  in  alluvium  and  till; 
water  rises  to  15  feet  below  the  surface.  Other  wells  in  this  village  have  nearly  the 
same  depth  or  less,  none  coming  to  the  bed-rock;  but  it  was  reached  by  a  well  a  third 
of  a  mile  east,  at  a  depth  of  about  100  feet. 

Four  miles  south-southeast  of  Niverville,  in  the  northeast  quarter  of  section  5,  in 
this  same  township  7,  range  4  east,  Cornelius  Freesen's  well,  situated  on  the  Niverville 
beach,  passed  through  alluvium  and  glacial  drift,  65  feet,  and  shale,  30  feet,  obtaining 
an  ample  artesian  flow  of  excellent  water. 

In  the  southwest  quarter  of  this  section,  a  half  mile  from  the  foregoing,  Adam 
Freesen  has  a  similar  flowing  well,  107  feet  deep,  which  went  37  feet  into  the  shale. 


'  Eeport  of  the  Department  of  Agriculture  and  Statistics,  Manitoba,  for  1882,  p.  176. 
MON   XXV 37 


578  THE  GLACIAL  LAKE  AGASSIZ. 

This  is  said  to  be  the  deepest  of  about  twenty  flowing  wells  in  this  Mennonite 
Reserve,  their  range  of  depth  being  from  40  to  107  feet. 

Dominion  City. — James  Speuce,  Victoria  Flour  Mills :  Flowing  well,  170  feet  deep, 
in  alluvial  clay  and  till,  the  latter  very  hard  below  the  depth  of  120  feet;  bed-rock  not 
reached;  water  brackish,  flowing  feebly,  not  used. 

The  common  wells  of  this  village,  12  to  16  feet  deep,  have  good  water  which  seeps 
from  the  alluvial  clay. 

The  Roseau  River  has  much  softer  water  than  the  wells  and  most  of  the  short 
streams  of  this  region,  so  that  the  railway  tank  at  Dominion  Oity,  taking  water 
from  the  Roseau,  is  preferred  by  the  locomotive  engineers  above  any  other  source  of 
water  on  this  branch  line. 

Hmerson. — Wells  in  Emerson  range  from  10  to  25  feet  in  depth,  in  alluvial  clay, 
and  obtain  water  tolerably  good  for  drinking  and  cooking,  but  it  is  very  hard  and 
unsuited  for  laundry  use. 

West  Lynne. — Hudson  Bay  Company's  steam  flouring  mill:  Well,  108  feet  deep, 
dug  68  feet  in  alluvial  and  lacustrine  clay,  and  bored  40  feet  lower,  apparently  in  the 
same  deposit.  The  only  water  found,  not  enough  to  supply  the  engine,  is  that  which 
seeps  from  the  clay,  coming  almost  wholly  within  the  first  20  feet  below  the  surface. 
The  ordinary  wells  in  this  village,  14  to  18  feet  deep,  obtain  good  water,  seeping  in 
sufiQcient  amount  for  domestic  use. 

Artesian  tvells  near  Letellier  and  on  the  Low  Farm. — An  artesian  well  on  the  French 
Reserve  at  the  center  of  township  2,  range  1  east,  near  Letellier,  12  miles  northwest 
from  Emerson  and  West  Lynne,  is  250  feet  deep,  not  reaching  the  bed-rock.  It 
supplies  brackish  water,  which  is  drunk  by  cattle.  Another  artesian  well  of  similar 
depth  is  on  the  Low  Farm,  about  12  miles  west  of  Morris,  the  water  of  which  is  strongly 
saline. 

West  Selkirlc. — The  well  at  the  Lisgar  House,  100  feet  deep,  reached  the  bed-rock, 
which  is  limestone,  at  65  feet. 

Stonewall. — J.  B.  Rutherford's  flouring  mill :  Well,  82  feet  deep,  consisting  of  beach 
gravel  and  sand,  10  feet;  till,  2  feet;  and  limestone,  including  red  shaly  beds,  70  feet, 
to  the  bottom,  where  the  drill  fell  1  foot  and  water  rose  immediately  to  22  feet  below 
the  surface.  Several  other  wells  in  Stonewall  have  had  a  similar  experience,  obtain- 
ing water  which  rises  from  hoUows  in  the  limestone. 

Township  15,  range  2  east. — William  Andrew,  southeast  quarter  of  section  7 :  Well, 
94  feet  deep;  till  at  the  surface  and  to  a  depth  of  11  feet;  and  limestone,  83  feet, 
mostly  hard  and  of  light  buff  color,  but  inclosing  some  25  feet  of  reddish  shaly  beds 
between  the  depths  of  45  and  70  feet.  There  are  several  such  wells  in  the  same 
vicinity. 

Betweeyi  Pleasant  Home  and  Gimli. — Mr.  Andrew  states  that  about  25  miles  north- 
east from  the  last  a  well  between  Pleasant  Home  and  Gimli  has  been  sunk  120  feet, 
wholly  in  the  glacial  drift,  not  reaching  the  bed-rock. 


NOTES  OF  AETESIAJ^  AND  COMMON  WELLS.  579 

Bosser. — The  railway  well  at  Eosser  is  29  feet  deep,  iu  till,  wliicb  forms  tlie 
surface  there  and  east  to  Little  Stony  Mountain ;  water  rises  15  feet  from  a  sandy, 
layer  at  the  bottom. 

Townshij)  11,  range  1  east. — Eobert  D.  Bathgate,  section  27:  Well,  60  feet  deep; 
till,  24  feet,  from  which  alkaline  water  seeps ;  and  light  buff,  hard  limestone,  36  feet, 
and  coutinuing  lower;  water  of  good  quality  rises  from  the  bottom  to  20  feet  below 
the  surface.  Other  wells  in  this  vicinity  mostly  get  good  water  in  veins  or  thin 
layers  of  sand  and  gravel  contained  in  the  till. 

St.  Francois  Xavier. — On  Mr.  Nan  ton's  ranch,  about  10  miles  west  of  Headingly 
and  a  quarter  of  a  mile  south  of  the  Assiniboine,  a  well  114  feet  deep  passed  through 
alluvial  clay,  14  feet;  till,  34  feet;  limestone  of  light  cream  color,  47  feet;  and  reddish 
limestone,  19  feet.    Brackish  water  rises  from  the  bottom  to  14  feet  below  the  surface. 

Meadoio  Lea.^ — Section  30,  township  13,  range  2:  Wells  in  this  vicinity  range 
from  20  to  95  feet  in  depth,  and  are  wholly  in  till,  not  reaching  the  bed-rock. 

Township  13,  range  6. — Charles  Cuthbert,  section  21,  10  miles  north-northeast 
from  Portage  la  Prairie :  Well,  16  feet  deep;  soil  and  loamy  silt,  to  water  in  quicksand 
and  fine  gravel.  The  surface  here  is  only  a  few  feet  above  the  high-water  level  of 
Lake  Manitoba. 

Portage  la  Prairie. — The  common  wells  are  12  to  16  feet  deep,  being  black  soil, 
2  to  4  feet;  then  yellowish-gray,  loamy  silt,  the  alluvium  of  the  Assiniboine,  iu  wliich 
fragments  of  driftwood,  as  small  limbs  of  trees,  are  occasionally  found,  to  water  in 
quicksand  and  fine  gravel.  The  deepest  well  here  is  that  of  the  Manitoba  and  North- 
western Eailway  tank,  which  reaches  30  feet,  to  till  at  the  bottom,  obtaining  a  very 
large  supply  of  water. 

Township  12,  range  8. — Kenneth  McKenzie,  jr.,  in  the  north  edge  of  section  2,  close 
west  of  Eat  Creek :  Well,  dug  86  and  bored  72  feet,  to  a  total  depth  of  158  feet;  soil,  2 
feet;  sand,  4  to  5  feet;  yellow  till,  4  feet;  blue  till,  76  feet,  easy  to  excavate,  with  scanty 
intermixture  of  gravel,  but  containing  occasional  stones  up  to  1  foot  or  more  in  diam- 
eter, undoubtedly  true  till,  for  the  surface  generally  through  the  south  part  of  this 
township  has  plentiful  embedded  bowlders  ui>  to  2  or  3  feet  in  diameter;  below  was 
"hardpan,"  a  more  indurated  deposit  of  till,  very  hard  to  dig  or  pick,  bored  or  drilled 
72  feet,  and  found  to  vary  much  in  its  hardness  through  this  dei^th,  some  j)ortions 
being  much  softer  than  where  the  boring  began.  A  seam  of  sand  and  fine  gravel, 
about  an  inch  thick,  was  noticed  between  the  upper  part  of  the  till,  which  was  dug, 
and  the  harder  lower  portion.  At  the  bottom  the  drill  struck  a  harder  layer,  which 
was  called  rock.  It  was  probably  shale,  for  the  drill,  being  dropped  a  few  times  upon 
it,  seemed  in  danger  of  becoming  stuck  so  that  it  could  not  be  removed.  Water  rose 
from  the  bottom  within  the  first  day  to  a  depth  of  20  or  30  feet  in  the  portion  of  the 

'Here  and  onward,  through  the  following  pages,  the  ranges  are  numbered  westward  from  the  ref- 
erence meridian. 


580  THE  GLACIAL  LAKE  AGASSIZ. 

well  that  was  dug,  and  within  a  few  days  it  reached  its  permanent  level,  abont  20  feet 
below  the  surface.  It  does  not  sink  below  this  level  iu  dry  seasons,  but  in  wet  seasons 
it  rises  to  7  feet  below  tlie  surface,  near  tlie  bottom  of  the  sand.  It  is  somewhat 
salty,  so  that  it  is  not  suitable  for  house  use,  but  it  is  drunk  freely,  and  with  no  ill 
eii'ect,  by  horses  and  cattle  during  the  entire  winter. 

A  (juarter  of  a  mile  soiith  of  this  Mr.  McKenzie's  father  has  a  similar  well  as  to 
its  depth  and  succession  of  deposits  passed  through  to  rock,  but  it  obtains  a  less  ample 
supi^ly  of  water.  Both  wells  are  864  feet,  approximately,  above  the  sea;  and  the  top 
of  the  bed-rock  is  accordingly  about  706  feet  above  the  sea  level. 

Gladstone. — Wells  vary  from  10  to  15  feet  in  depth,  in  sandy,  fine  silt.  Water 
abundant  and  of  excellent  quality. 

Arden. — In  the  vicinity  of  Arden  wells  are  10  to  50  feet  deep,  the  section  being 
till,  excepting  where  this  is  overlain  by  beach  deposits  from  5  to  15  feet  thick. 

Neepawa. — John  A.  Davidson  &  (Jo.,  store:  Well,  60  feet,  the  deepest  in  the 
town;  soil,  2  feet;  gravel  and  sand  of  the  Assiniboine  delta,  12  feet;  and  till,  dark 
bluish,  with  the  usual  proportion  of  gravel  and  bowlders,  46  feet,  and  extending  below; 
water  good.     Other  wells,  mostly  15  to  25  feet  deep,  reach  till  at  nearly  the  same  depth. 

Township  13,  range  16. — The  deepest  wells  in  this  township  go  50  to  70  feet,  wholly 
in  till;  but  commonly  a  sufiBcient  supply  of  water  is  found  within  30  feet  or  less. 

Carherry. — Wells  10  to  20  feet  deep  iu  sand,  the  Assiniboine  delta;  plenty  of 
good  water. 

Chater. — At  the  elevator,  42  feet,  and  at  the  hotel,  31  feet,  wholly  in  till,  yellowish 
above  and  dark  bluish  below;  water  rose  several  feet. 
,    Brandon. — Wells  10  to  30  feet  deep,  in  delta  gravel,  underlain  by  till ;  good  water. 

Carman. — Depths  10  to  15  feet,  in  alluvial  clay,  with  sandy  layers ;  good  water. 
Two  miles  south  of  Carman,  James  Stewart's  and  George  E.  Laidlaw's  wells  are, 
respectively,  about  100  and  120  feet  deep,  probably  passing  through  the  alluvial  and 
lacustrine  clays  and  glacial  drift  to  underlying  Cretaceous  shales.  The  water  of  the 
deeper  of  these  is  too  brackish  for  house  use,  but  is  drunk  by  cattle. 

Treherne. — In  the  vicinity  of  Treherne  wells  vary  from  15  to  50  feet  in  depth,  the 
section  being  beach  and  delta  deposits  of  stratified  gravel  and  sand;  excellent  water. 

HoUand. — Wells  at  Holland  are  10  to  20  feet  deep,  in  till  to  shale,  which  is  reached 
at  about  10  feet;  water  good,  generally  better  from  the  shale  than  from  the  drift. 
Shale  is  not  encountered  by  wells  farther  north,  on  the  Assiniboine  delta.  In  the 
adjoining  Tiger  Hills,  on  the  south,  the  depth  to  shale  varies  commonly  from  2  or  3  to 
10  or  15  feet. 

Cypress  River  and  Glenboro. — Depths,  10  to  17  feet,  in  fine  silt,  the  delta  of  the 
Assiniboine ;  water  good,  issuing  from  quicksand. 

Township  8,  range  18. — Eounthwaite  iiost-ofiQce,  section  14:  Well,  20  feet  deep; 
soil,  2  feet;  yellowish  gray  till,  13  feet;  harder  blue  till,  5  feet  and  lower;  water  seeps, 
plentiful  and  good. 


NOTES  OF  AETESIAN  AND  COMMON  WELLS.  581 

Township  7,  range  17. — Williamson,  Dignum  &  Co.,  farmhouse  iu  section  3:  Well, 
dug  30  feet  and  bored  313  feet  more;  seen  while  the  boring  was  in  i)i'ogress  at  depth 
of  62  feet;  all  till,  mostly  yellowish,  to  that  depth.  This  is  half  a  mile  north  of  the 
northern  base  of  the  Tiger  Hills,  at  an  elevation  of  about  1,350  feet  above  the  sea. 

Langs  Valley. — Langvale  post-ofBee.  at  James  Lang's  house,  section  2,  township 
6,  range  18:  Well,  18  feet  deep;  all  gravel  and  sand,  with  quicksand  at  the  bottom. 
This  is  on  the  bed  of  the  channel  of  outflow  to  the  Pembina  from  the  glacial  lake  iu 
the  Souris  basin. 

Plum  Greek. — Wells  in  this  village,  at  the  junction  of  Plum  Creek  with  the  Souris, 
are  10  to  30  feet  deep,  in  till,  not  reaching  bed-rock;  but  outcrops  of  the  Fort  Pierre 
shale  occur  ou  the  Souris,  near  by. 

Gretna. — Common  wells,  10  to  20  feet  deep,  iu  alluvial  and  lacustrine  clay,  obtain- 
ing a  scanty  supply  of  water.  A  boring  is  said  to  have  been  made  here  for  the  railway 
tank,  to  a  depth  of  150  feet,  without  finding  a  supply  of  water,  and  it  is  now  pumped 
from  the  Pembina  Eiver. 

Bheinland. — Wells  15  to  20  feet  deep,  in  somewhat  sandy  lacustrine  clay ;  excellent 
water. 

Township  3,  range  5. — John  Johnston,  section  3 :  Well,  22  feet ;  soil,  2  feet ;  yel- 
lowish till,  containing  bowlders  up  to  5  feet  in  diameter,  20  feet;  to  gravel  with  water 
which  rises  from  it  2  or  3  feet.  This  is  between  the  Campbell  and  Tintah  beaches, 
on  the  low  terrace  at  the  foot  of  the  Pembina  Mountain  escarpment.  Other  wells 
near  show  that  this  terrace  consists  of  the  Fort  Pierre  shale,  thinly  covered  with 
glacial  drift. 

Morden  and  Nelson. — The  deep  boring  recently  made  unsuccessfully  for  artesian 
water  at  Morden  has  been  described  on  page  81. 

Common  wells  in  Morden  and  Nelson  are  10  to  25  feet  deep,  in  alluvial  silt  and 
underlying  till;  water  frequently  alkaline. 


CHAPTER  XL 

AGRICULTURAL  AND  MATERIAL  RESOURCES  OF  THE  AREA 

OF  LAKE  AG-ASSIZ. 

Agriculture  must  evidently  be  always  the  chief  industry  and  source  of 
wealth  throughout  the  prairie  portion  of  the  area  of  Lake  Agassiz,  attended, 
in  villages  and  towns,  by  needed  branches  of  trade  and  manufactures. 
The  great  fertility  of  this  district  and  its  capabilities  for  agriculture  depend 
largely  on  the  character  of  the  underlying  alluvial,  lacustrine,  and  drift 
foi-mations,  which  in  their  diverse  development  upon  different  tracts  give 
considerable  variety  to  the  soils.  Beyond  and  above  the  inherent  qualities 
of  the  land,  its  value  to  the  farmer  and  herdsman  is  further  dependent  in  a 
very  large  degree  on  the  climatic  conditions  which  are  brought  by  the 
changing  seasons  of  the  year.  Both  these  factors  of  agricultural  prosperity 
had  expression,  before  the  land  was  cultivated  or  pastured,  in  the  native 
flora  of  the  country  and  in  its  former  herds  of  elk,  antelopes,  and  bufi"aloes. 
After  the  consideration  of  these  sources,  conditions,  and  natural  evidences  of 
the  adaptation  of  this  district  for  diversified  and  successful  agriculture,  the 
development  of  this  industry  is  shown  by  a  partly  statistical  review  of  its 
rapid  progress  in  the  production  of  wheat  and  other  crops  and  in  stock 
raising  and  dairying. 

The  more  strictly  geologic  resources  of  this  region  are  next  noticed, 
comprising  its  building  stone,  lime,  and  bricks,  all  of  which,  and  especially 
the  last,  have  much  economic  importance.  Mention  is  also  given  to  its  salt 
springs,  lignite,  and  natural  gas,  none  of  which,  however,  occurs  in  such 
amount  that  it  can  be  profitably  utilized. 

Lastly,  the  water  power  and  other  natural  aids  for  the  development  of 
manufactm-es  within  the  area  of  this  glacial  lake  are  considered.  Some 
of  its  streams,  as  the  Red  Lake  and  Clearwater  rivers,  the  upper  part  of  the 
Red  River  before  it  enters  this  lacustrine  area,  and  especially  the  Winnipeg 

582 


AGEICULTUEAL  AND  MATERIAL  EESOUECES.  583 

River,  are  unsurpassed  in  the  value  of  their  water  power,  which  can  be 
made  uniform  throughout  the  year  by  using  the  lakes  tributary  to  these 
streams  for  reservoirs.  Probably  much  of  the  wooded  portion  of  the  coun- 
try that  was  covered  by  Lake  Agassiz  will  be  cleared  and  used  as  farming 
land;  while  the  waterfalls  and  rapids  which  abound  on  rivers  within  the 
Archean  part  of  the  wooded  district  will  become  the  sites  of  manufacturing 
villages  and  cities. 

VARIETY   AND  DISTRIBUTIOK  OF  THE  SOILS. 

Over  nearly  the  entire  prairie  district  of  Lake  Agassiz  and  upon  the 
higher  and  more  undulating  or  rolling  country  ths,t  stretches  thence  west- 
ward, a  sandy  clay,  often  with  some  intermixture  of  gravel  and  occasional 
bowlders,  forms  the  soil,  which  has  been  colored  black  to  a  depth  of  1  or  2 
feet  below  the  surface  by  decaying  vegetation.  The  alluvial  and  lacustrine 
beds,  or  the  glacial  drift,  the  same  as  the  soil,  excepting  that  they  are  not 
enriched  and  blackened  by  organic  decay,  continue  below,  being  usually 
yellowish  gray  to  a  depth  of  10  or  15  feet,  but  darker  and  bluisli  beyond, 
as  seen  in  wells.  The  glacial  drift  contains  many  fragments  of  Cretaceous 
shale,  magnesian  limestone,  granites,  and  crystalline  schists;  and  its  fine 
detritus  and  the  silty  deposits  carried  into  Lake  Agassiz  by  its  tributaries 
are  mixtures  of  these  pulverized  rocks,  presenting  in  the  most  advantageous 
proportions  the  elements  needed  by  growing  plants. 

The  till  or  glacial  drift  of  this  region  is  remarkably  contrasted  with 
that  of  New  England  and  the  other  Northern  States  westward  to  the  Missis- 
sippi River  by  its  containing  a  smaller  proportion  of  bowlders,  cobbles,  or 
comparatively  small  rock  fragments  and  gravel.  On  an  average  the  surface 
of  the  till  in  this  southwestern  part  of  the  area  of  Lake  Agassiz  has  proba- 
bly not  more  than  one-twentieth  as  many  bowlders  as  the  average  in  the 
States  farther  east.  They  are  so  few  that  they  present  no  obstacle  to 
the  cultivation  of  the  soil,  except  on  the  occasional  morainic  belts,  where 
bowlders  are  plentiful,  often  strewing  the  ground  upon  limited  tracts, 
which  usually  are  knolly  and  hilly.  These  tracts  can  not  be  profitably 
subjected  to  tillage,  but  have  generally  a  fertile  soil  and  afford  excellent 


584  THE  GLACIAL  LAKE  AGASSIZ. 

pasturage.  The  smooth,  gently  undulating  or  nearly  flat  areas  of  till, 
which  are  far  more  extensive  than  the  morainic  belts,  can  be  plowed  often 
across  a  distance  of  several  miles,  bounded  only  by  stream  courses,  with- 
out encountering  a  bowlder  or  tree  or  bush  to  require  the  plow  to  deviate 
from  its  straight  and  continuous  furrow.  The  few  bowlders  which  are 
found  on  these  lands,  seldom  exceeding  3  to  5  feet  in  diameter  and  varying 
in  numbers  from  perhaps  one  to  five  or  ten  per  acre,  are  scarcely  so  many 
as  the  farmer  desires  for  the  construction  of  cellar  walls,  foundations  of 
buildings,  and  for  other  uses. 

Large  portions  of  the  deltas  of  Lake  Agassiz,  and  the  whole  of  the 
broad,  flat  expanses  of  lacustrine  and  alluvial  silt  which  adjoin  the  Red 
River,  have  no  bowlders  nor  gravel.  Here  the  ideal  conditions  are  found 
for  the  cultivation  of  single  fields  of  grain  occupying  hundreds  or  thou- 
sands of  acres.  Though  the  subsoil  of  many  arable  tracts  of  the  Red 
River  Valley  is  saturated  with  moisture  throughout  the  year  at  the  depth 
of- only  a  few  feet  below  the  surface,  even  these  moist  areas  have  sufficient 
slopes  to  drain  away  the  water  of  snow-melting  and  the  rains  of  spring  in 
season  for  early  sowing.  While  the  soil  of  both  the  till  and  the  lacustrine 
and  allu%dal  deposits  is  prevailingly  clayey,  it  yet  is  nearly  everywhere 
sufficiently  sandy  and  porous  to  permit  a  part  of  these  waters  and  a  large 
proportion  of  the  summer  rains  to  be  absorbed  by  it.  Whenever  a  tem- 
porary drought  comes,  the  water  thus  received  and  stored  at  a  moderate 
depth  in  the  subsoil  is  raised  by  capillary  attraction  to  the  surface.  The 
roots  of  vegetation  are  thus  nourished,  and  the  growth  of  the  crops  is  con-, 
tinned  without  check  or  a  bountiful  harvest  is  often  matm-ed  without  the 
aid  of  rainfall  during  a  month  or  more. 

Some  tracts  of  the  Red  River  Valley  are  marsh,  owing  to  the  flatness 
of  the  land  and  the  depression  of  these  tracts  a  few  feet  below  their  natural 
avenues  of  drainage.  The  marshes  vary  in  extent  from  patches  of  a  few 
hundred  acres  up  to  50  square  miles. 

An  enumeration  of  the  most  noteworthy  of  these  boggy,  partially 
inundated  areas  in  Minnesota  includes  the  marsh,  6  miles  in  diameter,  occu- 
pying the  greater  part  of  Winchester,  Norman  County,  in  crossing  which 
the  south  branch  of  the  Wild  Rice  River  becomes  diffused  and  lost,  until  it 


DRAINAGE  OF  MAESHY  TRACTS.  585 

is  gathered  again  on  the  western  border  of  the  marsh  by  the  union  of  tlie 
waters  of  many  rills,  brooklets,  and  springs;  the  marshy  grounds  in 
Anthony  and  Halstad  townships,  also  in  Norman  County,  lying  on  each 
side  of  tlie  Marsh  River;  the  great  swamp  in  southwestern  Polk  County, 
in  which  the  Sand  Hill  River  is  lost  for  about  8  miles,  being  again  formed 
by  many  brooks  that  ilow  from  the  western  edge  of  the  swamp  along  a  dis- 
tance of  5  miles  from  south  to  north ;  the  Snake  River  marsh  in  Sandsville, 
on  the  north  line  of  Polk  County;  the  marsh  in  Bloomer,  Parker,  and  Big 
Woods,  Marshall  County,  in  which  the  Middle  River  is  lost  for  5  miles  next 
above  its  junction  with  the  Snake  River;  and  the  large  swamp  in  the  north- 
ern edge  of  this  county,  extending  also  into  Kittson  County,  formed  by 
the  outspread  waters  of  the  Tamarack  River,  which  is  thus  lost  across  a 
distance  of  8  miles. 

Excavation  of  channels  for  these  rivers  through  their  marshes  and  for 
a  distance  of  several  miles  below  them  to  the  depth  of  5  to  10  feet  below 
the  present  waterways,  with  the  cutting  of  side  ditches  in  the  marshes, 
will  drain  these  wet  lands,  which  will  then  have  a  very  deep  and  fertile  soil, 
sufficiently  dry  for  tillage,  being  doubtless  the  best  and  most  enduring  in 
productiveness  among  all  the  rich  lands  of  this  valley  plain.  A  survey  for 
a  plan  of  drainage  of  the  eastern  side  of  the  Red  River  Valley,  lying  in 
Minnesota,  was  made  in  1886;  and  the  estimate  by  Mr.  C.  G.  Elliott,  the 
engineer  in  charge,  for  the  expenditure  needed  to  provide  the  main  ditches 
and  to  deepen  the  existing  watercourses  is  $746,228.  The  number  of 
acres  to  be  benefited  by  the  drainage  is  808,600,  .showing  an  average  cost 
of  92  cents  per  acre.  Minor  ditches,  which  will  be  dug  on  each  side  of  the 
roads,  following  the  section  lines,  are  not  included  in  this  estimate. 

The  jjart  of  this  flat  valley  in  North  Dakota  is  dotted  here  and  there 
with  many  small  marshes,  but  with  very  few  that  have  so  large  an  area  as 
several  square  miles.  The  most  considerable  in  size  are  the  marsh,  2  to  3 
miles  across,  in  Berlin  and  Hammond,  Cass  County,  in  which  the  Rush 
River  is  lost;  marshes  adjoining  Salt  Lake,  through  wliich  the  Forest  River 
flows  in  Ardoch,  Walsh  County;  and  a  low  meadow,  mostly  mown  for  its 
marsh  hay,  but  in  small  part  a  permanent  bog,  extending  12  miles  from 


586  THE  GLACIAL  LAKE  AGASSIZ. 

south  to  north,  with  a  width  of  a  half  mile  to  2  miles,  in  the  east  part  of 
Midland,  Pembina  County. 

In  both  Minnesota  and  North  Dakota  these  bogs  are  destitute  of  trees 
and  shrubs,  and  are  occupied  mostly  by  rushes,  sedges,  and  marsh  grasses, 
which  usually  attain  a  very  rank  growth.  No  malarial  diseases,  however, 
are  produced  by  the  marshes  in  then-  present  condition,  and  the  principal 
injury  to  be  charged  against  them  is  that  they  hinder  or  prevent  the  con- 
struction of  roads  which  would  be  a  public  convenience.  So  long  as  they 
remain  undrained,  these  lands  are  almost  or  quite  worthless,  but  when  well 
di-ained  and  brought  under  cultivation  they  will  be  a  great  addition  to  the 
wealth  and  resources  of  tliis  fertile  valley. 

East  of  the  Red  River  Valley,  the  wooded  part  of  the  area  of  Lake 
Agassiz  in  northern  Minnesota  contains  frequent  swamps,  ranging  from  a 
few  acres  to  many  square  miles  in  area,  usually  occupied  by  a  sparse 
growth  of  tall  and  slender  tamarack  and  black  spruce  trees,  but  in  their 
central  portions  often  destitute  of  trees  and  covered  by  peat  mosses,  in 
which  there  may  be  a  pool  or  lakelet,  either  of  clear  water  or  filled  with 
rushes.  Extensive  swamps  of  this  kind,  locally  called  muskegs,  adjoin  Red 
Lake,  Mud  and  Thief  lakes,  the  Lake  of  the  Woods,  and  Roseau  Lake. 
Indeed,  they  are  reported  as  covering  a  large  part  of  the  country  northeast- 
ward from  Red  Lake  to  the  international  boundary,  forming  a  region 
which  is  well-nigh  impassable  excepting  in  winter,  when  the  surface  of  the 
muskegs  is  frozen. 

The  vast  forest  region  of  Lake  Agassiz  comprised  within  Canadian 
territory  has  many  scattered  muskegs,  but  also  much  laud  with  dry  and 
rich  soil,  worthy  to  be  cleared  and  cultivated,  tlu'oughout  all  its  extent  from 
Rainy  Lake  and  River  and  the  Lake  of  the  Woods  northwestward  by  the 
great  lakes  of  Manitoba  to  the  Saskatchewan.  During  many  years  to  come 
no  attempt  will  probably  be  made  to  utilize  the  swamps  or  muskegs  of  the 
wooded  country;  but  in  Manitoba,  as  already  noted  in  Minnesota,  many 
of  the  marshes  and  swamps  of  the  prahie  region  are  being  drained  for 
agricultm-e.  The  main  ditches  are  dug  as  a  part  of  the  public  improve- 
ments by  the   Provincial  Government,  which  is  reimbursed  by  the  sales 


MAESHES  IN  MANITOBA.  587 

of  the  marsh  lands,  worthless  before  they  are  drained,  but  afterward  very- 
valuable. 

Several  of  the  prairie  marshes  of  Manitoba,  lying  west  of  the  Red 
River  and  on  both  sides  of  the  Assiniboine,  range  in  extent  from  20  to  75 
square  miles,  namely,  the  marsh  in  which  Tobacco  Creek  is  spread  out  and 
lost  east  of  Pomeroy;  the  great  marsh  similarly  formed  by  the  waters  of 
the  Boyne  River  and  Elm  Creek,  extending  15  miles  from  west  to  east,  with 
a  width  of  3  to  6  miles,  overflowing  southeastward  to  the  Red  River  by 
the  Riviere  aux  Gratias;  the  Squirrel  Creek  marsh,  lying  close  south  of  the 
White  Mud  River,  between  Westbourne  and  Woodside,  formed  by  Image, 
Beaver,  Squirrel,  Pine,  and  Silver  creeks,  which  come  from  the  northeastern 
slope  of  the  Assiniboine  delta;  and  the  Big  Grass  marsh,  extending  more 
than  20  miles  from  south  to  north,  with  a  width  of  3  to  5  miles,  in  which 
the  White  Mud  and  Big  Grass  rivers  are  lost  or  flow  sluggishly  through 
a  broad,  quaking  morass,  with  shallow,  rush-filled  lakes  along  its  axial 
portion. 

Commonly  the  water  of  the  marshes  is  supplied  almost  wholly  by 
inflowing  streams  and  by  rainfall,  but  in  some  instances  they  receive  a 
large  part  of  their  water  from  springs.  Multitudes  of  copious  springs  of 
fresh  water,  issuing  from  thick  beds  of  sand  and  gravel  which  eastward 
are  overlain  by  till,  form  the  very  remarkable  boggy  tract,  a  half  mile  to 
1  mile  wide,  which  extends  about  9  miles  from  south  to  north  along  the 
highest  shore  of  Lake  Agassiz  in  Akron  and  Tanberg,  Wilkin  County,  Minn. 
Unlike  the  level  marshes  before  enumerated,  this  tract  lies  on  a  slope  which 
descends  20  to  40  feet  upon  the  width  of  the  marshy  gi'ound  from  east  to 
west.  On  such  a  slope  the  marsh  can  be  maintained  only  by  the  constant 
issuance  of  spring  water  tlu-ough  all  portions  of  its  bed.     (See  pp.  286,  385.) 

In  several  other  marshes  of  smaller  extent,  as  on  the  Salt  Cooley  and 
Salt  River,  near  Ojata,  tributary  to  the  Turtle  River,  and  on  the  Forest 
and  Park  rivers,  it  is  known  that  saline  springs  come  up  within  the  area  of 
the  marshes,  because,  although  the  streams  flowing  into  them  are  fresh,  the 
outflowing  water  is  brackish. 

Throughout  nearly  all  the  part  of  the  Red  River  Valley  where  brack- 
ish water  is  found  by  the  artesian  wells,  and  where  it  infrequently  outflows 


588  THE  GLACIAL  LAKE  AGASSIZ. 

in  springs,  as  just  noted  and  as  observed  in  the  channels  of  Two  Rivers  and 
other  streams,  there  are  noticed  also  occasional  and  rare  patches  of  ground, 
usually  no  more  than  a  few  square  rods,  or  at  most  a  few  acres,  in  extent, 
on  which  wheat,  oats,  or  other  crops,  after  germinating  and  beginning  an 
apparently  healthy  growth,  are  soon  dwarfed  or  killed,  while  closely  adjoin- 
ing land,  sometimes  scarcel}^  distinguishable  in  the  appearance  of  the  soil, 
is  yet  divided  from  the  preceding  by  rather  definite  boundaries,  as  shown 
by  the  healthful  growth  of  vegetation  and  a  satisfactory  harvest.  These 
peculiar  spots  fail  year  after  year  to  produce  any  crop,  and  their  exceptional 
character  in  fields  which  mainly  have  a  bountiful  growth  of  waving  grain 
is  a  source  of  wonder  and  much  conjecture  to  many  farmers.  They  are 
very  simply  explainable,  however,  as  the  places  to  which  the  saline  and 
alkaline  artesian  and  spring  water  percolates  upward  through  veins  and 
layers  of  gravel  and  sand  and  somewhat  porous  or  creviced  tracts  of  the 
till  and  lacustrine  and  alluvial  beds,  until  it  comes  to  the  surface  and  is 
there  diffused  through  the  soil  of  a  small  or  somewhat  large  area,  thus 
affecting  vegetation,  though  not  issuing  in  sufficient  quantity  to  produce 
springs. 

Although  the  bowlders  of  the  till  within  the  basin  of  the  Red  Ri%'er 
are  mostly  Archean  granite,  gneiss,  and  crystalline  schists,  derived  from  the 
northeast  and  north,  with  few— probably  on  an  average  less  than  1  per 
cent — of  niagnesian  limestone,  derived  from  Silurian  and  Devonian  forma- 
tions underlying  the  drift  and  outcropping  northward  in  Manitoba,  the  latter 
forms  a  very  considerable  proportion,  usually  more  than  half,  of  the  smaller 
rock  fragments  inclosed  in  the  till  and  of  the  gravel  in  modified  drift  and 
alluvial  deposits.  Owing  to  the  greater  prevalence  of  joints  in  the  lime- 
stone, it  has  been  reduced  more  readily  to  the  size  of  gravel,  and  it  probably 
has  contributed  at  least  as  much  as  the  Archean  rocks  to  the  sandy  and 
clayey  matrix  of  the  till,  pulverized  by  the  grinding  action  of  the  ice-sheet. 
The  powdered  limestone  is  one  of  the  most  important  ingredients  of  the 
drift.  Dissolved  in  the  water  of  wells  and  springs,  as  noted  in  the  preceding 
chapter,  it  makes  them  hard,  diminishing  their  desirability  for  washing  and 
for  use  in  the  boilers  of  steam  engines,  but  not  for  drinking  and  cooking. 
On  the  other  hand,  this  element  contributes  a  large  share  toward  making 


CAUSE  OF  ALKALINE  SOILS.  589 

the  very  fertile  soil  of  this  district  and  producing  the  magnificent  liarvests 
of  wheat  which  are  its  principal  export  and  source  of  wealth. 

A  still  larger  proportion  of  the  drift  upon  the  jn-airie  district  of  Lake 
Agassiz  was  supplied  from  the  Fort  Pierre,  Niobrara,  and  Fort  Benton 
shale  formations  of  the  Cretaceovis  series.  They  are  mostly  soft  shales, 
however,  and  therefore  have  supplied  no  bowlders;  nor  are  they  usually 
represented  conspicuously  by  pebbles  of  the  till  and  in  gravel  deposits, 
excepting  near  the  western  border  of  the  ancient  lake,  where  the  Pembina 
Mountain  escarpment  and  plateau,  the  basal  part  of  the  Tiger  Hills,  and 
the  Riding  and  Duck  mountains,  consist  of  these  shales.  Many  streams 
flowing  down  from  these  highlands  have  cut  deep  ravines  and  valleys  in 
their  frontal  escarpment,  and  have  spread  much  shale  gravel  outward  for 
several  miles  along  the  Avatercourses  on  the  Red  River  Valley  i)lain.  The 
till  or  glacial  drift  on  this  western  margin  of  the  lacustrine  area  and  on 
all  the  plateau  country  extending  thence  westward  has  also  a  consider- 
able ingredient  of  shale  gravel.  But  the  greater  part  of  the  material 
contributed  from  these  shale  beds  to  the  glacial  drift  is  mingled  with  the 
pulverized  Archean  granite  and  gneiss  and  Paleozoic  limestones,  doubtless 
generally  far  surpassing  these  as  a  constituent  of  the  finely  comminuted 
rock  flour  which  is  the  most  abundant  element  of  tlie  bowlder-clay  or  till. 

The  portion  of  tlie  till  thus  received  from  the  Cretaceous  beds  has 
given  to  its  soil  the  somewhat  alkaline  character  which  is  perhaps  the  most 
noteworthy  quality  distinguishing  the  soil  of  this  district  and  of  the  plains 
on  the  west,  in  contrast  with  the  soil  of  the  Northern  States  and  Canadian 
provinces  east  of  Lake  Agassiz.  The  sulphates  of  magnesia  and  soda,  with 
other  soluble  salts,  together  termed  "alkali,"  which  are  present  in  consid- 
erable amount  in  the  glacial  drift  of  the  Red  River  Valley  and  the  western 
plains,  are  almost  wholly  due  to  the  contribution  of  the  Cretaceous  shales 
to  the  drift.  This  soluble  mineral  matter  was  contained  in  the  Cretaceous 
ocean,  and  much  of  it  became  imprisoned  and  stored  up  in  the  very  fine 
clayey  sediments  of  that  time.  On  the  areas  of  these  shale  formations 
beyond  the  limits  of  the  glacial  drift  the  soil  is  far  more  alkaline  than 
within  this  region,  where  Archean,  Paleozoic,  and  Cretaceous  strata  have 


590  THE  GLACIAL  LAKE  AGASSIZ. 

joined  in  making  tip  the  drift  tlu-oug-h  the  grinding  and  kneading  action  of 
the  ice-sheet 

Foregoing  descriptions  and  analyses  of  the  waters  of  wells,  lakes,  and 
streams  have  sufficiently  indicated  the  efiFects  of  this  alkaline  matter  of  the 
soil  upon  the  water  supply.  At  the  same  time,  the  result  of  evaporation 
from  the  soil  during  droughts,  often  producing  on  previously  moist  tracts 
a  saline  and  alkaline  efflorescence,  was  also  noticed.  Shallow  and  flat 
depressions,  into  which  the  alkaline  matter  is  brought  by  drainage  from 
higher  adjoining  land,  thus  may  have  many  times  more  of  the  soluble  salts 
in  their  soil  than  the  average  of  the  district ;  and  when  these  tracts  become 
dry  and  their  moisture  from  a  considerable  dei:)th  is  di'awn  upward  and 
evaporated  at  the  surface  it  leaves  a  whitish-gray  alkaline  incrustation. 
These  low  alkaline  lands  are  unfit  for  agriculture  until  they  have  been  well 
drained  during  several  years,  which  may  frequently  be  done  by  ditches 
only  a  few  feet  deep,  leading  into  lower  watercourses.  Excepting  such 
depressions  and  the  marshes  and  sloughs  before  described,  all  the  land  of 
this  district  has  at  least  the  very  slight  slopes  necessary  for  free  di'ainage, 
and  is  well  adapted  for  the  cultivation  of  wheat,  oats,  and  other  cereals, 
and  of  the  common  garden  vegetables  and  small  fruits  that  are  suited  to 
the  climate.  The  proportion  of  alkaline  matter  in  the  till  soils  wherever 
they  have  natural  di-ainage  is  not  prejudicial  but  rather  advantageous  for 
wheat  and  other  grains. 

Along  the  axial  belt  of  the  Red  River  Valley  plain  alluvial  clayey 
silt  usually  borders  the  river  to  a  distance  of  5  to  10  miles  on  each  side, 
and  other  tracts  are  covered  by  fine  lacustrine  sediments  of  nearly  the 
same  character,  bordering  the  pi'ominent  delta  jjlateaus.  These  areas  have 
a  somewhat  porous  soil,  composed  mostly  of  very  fine  sand  or  rock  flour 
rather  than  true  clay,  being  thus  similar  to  the  bowlder-clay  or  till;  but 
they  have  a  somewhat  less  proportion  of  the  soluble  alkaline  salts,  which 
in  the  process  of  aqueous  deposition  of  these  beds  were  partially  removed 
and  carried  away  by  the  rivers  into  the  sea. 

The  deltas  of  sand  and  gravel,  mainly  modified  drift  washed  away 
from  the  melting  ice-sheet  and  amassed  in  the  margin  of  Lake  Agassiz  by 
its  tributary  glacial  rivers,  also  contain  less  alkaline  matter  than  the  till. 


LAEGE  AREAS  ADAPTED  FOR  AGRICULTURE.        591 

They  liave  a  large  ingredient  of  limestone  gravel,  sand,  and  fine  detritus, 
so  that  their  soil  is  usually  fertile,  while  the  very  porous  subsoil  i^ermits 
early  sowing  and  is  favorable  for  the  rapid  growth  and  early  maturing  of 
crops. 

The  unique  tracts  of  dunes,  however,  consisting  of  bare  sand  di-ifted 
by  the  winds,  or  partly  or  wholly  covered  with  grasses  and  other  herbage, 
bushes,  and  small  trees,  which  occupy  extensive  portions  of  the  Sand  Hill, 
Sheyenne,  and  Assiniboine  deltas,  are  themselves  worthless  for  agricultural 
uses,  and  even  afford  only  scanty  pasturage.  But  many  well-grassed 
patches  of  ground  lie  in  the  hollows  among  the  dunes,  where  herds  find 
good  forage. 

Probably  the  parts  of  this  district  that  are  worthless  to  the  farmer, 
comjjrising  the  sand  hills,  the  alkaline  undrained  depressions,  permanently 
wet  sloughs,  the  steep  bluffs  or  banks  of  the  watercourses,  and  very  stony 
morainic  tracts,  amount  together  to  no  more  than  a  fiftieth  of  the  whole 
country.  Elsewhere  all  this  vast  area  is  fertile  and  easily  cultivated,  with 
considerable  diversity  in  the  soils  of  its  different  portions,  dependent  on 
the  nature  of  the  drift,  lacustrine,  and  alluvial  formations,  and  on  their 
conditions  of  drainage.  The  black  soil  has  usually  a  thickness  of  1  to  2 
feet,  this  color  being  due  to  enrichment  by  the  decaying  vegetation  of  all 
the  years  and  centuries  since  these  deposits  were  formed  during  the  Ice 
age  and  at  its  close. 

Looking  forAvard  to  no  very  distant  time,  it  may  be  foreseen  that  nearly 
all  the  land  here  will  be  brought  under  successful  cultivation,  and  that  a 
farming  population  of  probably  a  million  people,  perhaps  even  twice  or 
thi'ice  this  number,  will  live  on  the  prairie  area  of  Lake  Agassiz.  Many  of 
them  will  come  as  immigrants,  and  in  their  selection  of  this  rich  farming 
region  for  their  future  homes  the  most  important  inquiries  next  after  those 
concerning  the  native  quality  of  the  land  will  relate  to  climate.  The  rain- 
fall and  the  temperature  not  only  affect  very  closely  the  health  and  comfort 
of  the  people,  but  they  also  determine  whether  the  crops  sown  or  planted  in 
a  naturally  productive  soil  and  tended  with  patient  and  faithful  care  shall 
bring  forth  an  abundant  or  a  scanty  harvest. 


592 


THE  GLACIAL  LAKE  AGASSIZ. 


CLIMATIC  CONDITIONS. 

Six  stations  at  which  continuous  series  of  weather  observations  have 
been  made  are  here  selected  for  the  purpose  of  exhibiting  by  their  records 
the  general  climatic  conditions  of  the  southwestern  part  of  the  area  of  Lake 
Agassiz,  which  is  fast  becoming  occupied  by  a  dense  population  engaged  in 
agriculture.  Five  are  stations  of  the  United  States  Signal  Service,  naiiiely : 
St.  Paul,  where  observations  wei'e  begun  November  1,  1870;  Duluth,  also 
having  records  since  November  1,  1870;  Moorhead,  since  January  1,  1881; 
St.  Vincent,  since  September  5,  1880;  and  Bismarck,  since  September  15, 
1874.-'  With  these  are  also  inserted  the  records  of  observations  at  Winni- 
peg for  the  Meteorological  Bureau  of  the  Dominion  of  Canada,  beginning 
with  the  year  1871  and  published  up  to  the  year  1887,  inclusive. 

RAINFALL    AND    SNOWFALL. 

At  these  stations,  of  which  three  are  situated  on  the  Red  River,  the 
combined  amount  of  rainfall  and  snowfall  are  as  follows  for  their  series  of 
years,  with  the  resultant  means  deduced  from  each  seiies: 

Annual  and  mean  annual  precipitation,  in  inches. 


Stations. 

1871. 

1872. 

1873. 

1874. 

1875. 

1876. 

1877. 

1878. 

1879. 

1880. 

1881. 

St  Paul 

30.63 
31.20 

30.12 

34.75 
38.73 

35.51 
36.43 

30.66 
26.93 

23.67 
it2.27 

28.80 
34.31 

22.78 
28.09 

32.39 
45.28 

29.76 
38.11 

39.16 

Duluth 

37.56 

29.48 

St  Vincent 

15.51 

20.17 

30.17 

17.04 

18.31 

16.85 
27.52 

29.18 
30.92 

24.61 
17.68 

29.52 
20.23 

25.23 
22.61 

27.17 
19.75 

18.09 

15.76 

Mean  for  entire  district.. 

27.33 

30.17 

30.08 

25.49 

29.01 

26.35 

25.15 

31.38 

28.70 

25.93 

Stations. 

1682. 

1883. 

1884. 

1885. 

1886. 

1887. 

1888. 

1889. 

1890. 

Mean  annual. 

Tears. 

Mean. 

St.  Paul 

23.14 
38.  02 
34.01 
22.48 
20.75 
21.  33 

26.70 
23.20 
24. 9G 
17.88 
19.22 
15.66 

26.11 
35.85 
28.50 
21.81 
25.13 
23.36 

25.33 
19.96 
22.68 
16.58 
16.52 
13.08 

22.89 
33.37 
26.76 
15.04 
14.84 
13.26 

25.85 
28.56 
21.97 
18.47 
17.98 
16.33 

25.86 
27.31 
16.50 
17.22 

16.96 
32.04 
17.07 
14.44 

23.38 
24.09 
21.79 
22.09 

19 
20 
10 
10 
17 
16 

27.60 

Duluth            

32.07 

24.37 

18.15 

21.81 

16.51 

11.03 

15.75 

18.80 

Mean  for  entire  district.. 

26.62 

21.68 

27.13 

19.53 

22.26 

22.24 

20.68 

18.31 

21.42 

j       23.80 

'  Annual  Reports  of  the  Chief  Signal  Officer,  United  States  Army.     (In  the  year  1891  the  Weather 
Bureau  was  transferred  to  the  United  States  Department  of  Agriculture.) 


EAINFALL  AND  SNOWFALL. 


593 


The  amounts  of  the  average  or  normal  precipitation  for  each  month  at 
the  five  stations  in  the  United  States  from  the  date  of  their  establishment  to 
the  end  of  1886,  and  at  Winnipeg  during  the  fifteen  years  1871  to  1885, 


are  noted  in  the  following  table : 


^formal  precipUation,  in  inches,  for  each  month  of  the  i/ear. 


Stations. 

Janu- 
ary. 

Febru- 
ary. 

Maroli. 

April. 

May. 

June. 

July. 

Au- 
gust. 

Septem- 
ber. 

Octo- 
ber. 

Novem- 
ber. 

Decem- 
ber. 

St.  Paul 

Duluth      

1.03 

i.oe 

.77 
.36 
.57 
.54 

0.97 
I.U 
.98 
.40 
.97 
.64 

1.52 

1.56 

.88 

.30 

.89 

1.05 

2.25 
2.26 
2.38 
1.36 
1.56 
2.78 

3.34 
3.74 
3.04 
2.22 
2.37 
2.91 

4.83 
5.33 
4.47 
2.59 
3.62 
3.40 

3.26 
3.90 
4.59 
2.66 

2.87 
2.28 

3.67 
3.41 
3.42 
2.68 
3.08 
2.60 

3.38 
4.53 
2.42 
2.13 
1.91 
1.24 

2.05 
2.95 
2.77 
2.28 
1.51 
1.19 

1.37 
1.79 
1.25 
.56 
.86 
.75 

1.30 
1  31 

78 

.32 

1  00 

77 

Mean  for  entire 
district  

.72 

.85 

1.07 

2.10 

2.94 

4.04 

3.26 

3.14 

2.60 

2.12 

1.10 

.95 

From  these  tables  it  is  seen  that  the  mean  annual  precipitation  of 
moisture  as  rain  and  snow  at  difi'erent  places  in  this  district  ranges  from  18 
to  32  inches.  It  is  most  upon  the  wooded  country  east  and  northeast  of 
the  Red  River  Valley;  on  that  valley  plain  its  average  is  about  22  inches; 
but  westward  it  decreases  to  19  inches  at  Bismarck. 

The  most  plentiful  precipitation  is  during  the  season  of  the  growth  of 
crops,  increasing,  on  an  average  for  the  whole  district,  from  about  2  inches 
in  April  to  3  inches  in  May  and  4  inches  in  June,  which  is  usually  the  most 
rainy  month;  and  decreasing  to  about  3  inches  in  July,  nearly  the  same  in 
August,  and  2  J  inches  in  September.  But  many  years  depart  widely  from 
these  averages,  there  being  sometimes  during  several  consecutive  years  an 
excess  and  during  other  isolated  or  consecutive  years  a  deficiency  of  rain- 
fall. During  the  fifteen  to  twenty  years  since  agricultural  settlements  were 
first  made  in  the  Red  River  Valley  south  of  the  international  boundary, 
the  rainfall  and  temperature,  though  showing  marked  contrasts  in  diff'erent 
years,  have  always  been  so  favorable  for  farming  that  there  has  been  no 
instance  of  failure  on  this  valley  plain  to  secure  at  least  a  generally  remu- 
nerative harvest;  while  most  of  the  years  have  yielded  very  abundantly. 

A  large  portion  of  the  rainfall  is  brought  by  thunder  showers,  which 
may  occur  at  any  hour  of  the  day  or  night.     Terms  of  cloudy  and  more 
or  less  rainy  weather,  due  to  broad  storms  that  sweep  from  west  to  east, 
MON  XXV 38 


594  THE  GLACIAL  LAKE  AGASSIZ. 

occasionally  occupy  one,  two,  or  three  days,  or  very  rarely  a  whole  week; 
but  on  the  average,  in  all  seasons  of  the  year,  this  region  has  a  large 
majority  of  clear  days  with  bright  sunshine. 

In  addition  to  the  recorded  rainfall,  seasons  that  have  a  considerable 
supply  of  rain,  with  at  least  a  moderatel)'  humid  atmosphere,  receive  much 
moisture  in  the  form  of  the  nightly  dews,  which  greatly  help  the  growth 
of  crops;  but  in  seasons  of  di-ought,  with  an  arid  atmosphere,  when  all 
vegetation  gasps  for  moisture,  the  nights  condense  little  or  no  dew. 

In  winter  the  .snow  is  commonly  about  a  foot  deep  during  two  or  tlu-ee 
months,  from  December  or  January  to  March.  Sometimes  it  comes  earlier 
or  stays  later,  and  very  rarely  it  attains  an  average  depth  of  2  or  3  feet. 
Nearly  every  winter  has  from  one  to  three  or  four  severe  storms,  called 
blizzards,  in  which  the  snowfall  is  accompanied  by  a  fierce  wind  and  often 
by  very  low  temperature.  The  air  is  filled  with  flying  grains  of  snow,  by 
which  the  view  to  any  considerable  distance  is  obscured  and  the  traveler 
finds  his  eyes  soon  blinded  in  attempting  to  move  or  look  in  the  du-ection 
from  which  the  storm  comes.  The  earliest  snows,  which,  however,  are 
likely  to  be  soon  melted  away,  usually  fall  during  November,  but  very 
rarely  they  come  as  early  as  the  middle  of  September;  and  the  latest  snows 
vary  in  time  from  March  to  May. 

During  a  series  of  years  of  prevailingly  copious  rainfall  and  snowfall, 
extending  from  1871  or  earlier  to  1884,  agriculture  was  partially  or  gener- 
ally successful  upon  a  large  area  reaching  westward  from  the  southwestern 
borders  of  Lake  Agassiz  to  the  Missouri  River.  Then  a  series  of  five  pre- 
vailingly dry  years,  with  long  terms  of  severe  drought,  extended  to  1889, 
during  which  the  crops  of  that  area  were  mostly  very  scanty  and  for  large 
tracts  were  several  times  an  utter  failure,  bringing  great  distress  and  dismay 
to  the  people,  many  of  Avhom  were  compelled  to  abandon  their  lands  and 
homes  and  to  remove  to  more  favored  portions  of  the  country.  A  new 
cycle  of  plentiful  rainfall  appears  to  have  begun  in  1890,  1891,  and  1892, 
giving  again  magnificent  harvests  in  the  region  from  DcAals  Lake  to  Bis- 
marck and  southward,  Avhicli  had  suffered  most  severely  by  drought. 

Fluctuations  of  lakes  and  streams. — Tlu'ough  the  past  hundi'ed  years  max- 
imum and  minimium  stages  of  the  great  Laurentiau  lakes  have  alternated 


FLCrCTUATIONS  OF  DEVILS  LAKE.  595 

in  cycles  of  about  a  dozen  years,  dining  wliicli  comparatively  scanty 
average  rainfall  for  several  years  was  followed  by  unusually  abundant 
rainfall.^  These  fluctuations  are  similar  with  those  just  noted  in  the  rain- 
fall of  North  Dakota.  Besides  such  short  cycles,  important  secular  changes 
of  the  mean  annual  precipitation  in  this  State,  occupying  considerably 
longer  periods,  have  caused  remarkable  changes  in  the  levels  of  numerous 
lakes  which  have  no  outlets. 

Devils  Lake"  thus  shows  evidence  of  having  attained,  about  the  year 
1830,  a  level  16  feet  higher  than  its  low  stage  in  1889,  reaching  at  or  near 
the  former  date  to  the  line  that  limits  the  large  and  dense  timber  of  its 
bordering  groves.  Below  that  line  are  only  smaller  and  scattered  trees,  of 
wliich  Capt.  E.  E.  Heerman  informed  me  that  the  largest  found  by  him  and 
cut  a  few  years  ago  had  fifty-seven  rings  of  annual  growth.  Within  the 
twenty-five  years  since  the  building  of  Fort  Totten  this  lake  has  fallen  9  or 
10  feet,  and  it  has  fluctuated  4  feet  under  the  influence  of  the  changes  in  the 
,  average  annual  precipitation  of  rain  and  snow  during  the  past  dozen  years. 

The  high  stage  reached  by  this  lake  about  sixty  years  ago  appears  to 
have  been  limited  by  an  avenue  of  discharge  eastward  into  Stump  Lake, 
which  rose  at  the  same  time  to  within  about  3  feet  of  this  height.  The 
latter  and  smaller  lake,  receiving  no  large  tributary  and  lying  in  a  basin 
that  nowhere  extends  many  miles  from  the  lake,  was  prevented  by  evapo- 
ration from  rising  quite  so  high  as  Devils  Lake,  which  during  years  of 
abundant  raius  and  snows  receives  a  large  tributary,  the  Mauvaise  Coulee, 
draining  a  broad  area  that  stretches  60  miles  northwestward  to  the  Turtle 
Mountain.  The  outlet  from  Devils  Lake  into  Stump  Lake  was  nearly  due 
eastward  from  Jerusalem,  situated  on  Lamoreaux  Bay  at  the  most  eastern 
portion  of  the  entire  lake  shore.  With  an  ovei-flow  at  this  point,  Devils 
Lake  may  many  times  have  been  raised  to  this  beach  by  the  periodic 
variations  in  rainfall  during  the  many  centuries  since  the  Ice  age.^ 

'  Charles  Whittlesey,  "On  fluctuations  of  level  in  the  North  American  lakes,"  in  Smithsonian  Con- 
tributions to  Knowledge,  Vol.  XII,  1860,  pp.  2.5,  with  2  plates.  G.  M.  Dawson,  in  Nature,  Vol.  IX,  pp. 
504-506,  April  30,  1874.  Bela  Hubbard,  in  Popular  Science  Monthly,  Vol.  XXXII,  pp.  373-387,  Jan., 
1888.     G.  K.  Gilbert,  in  The  Forum,  Vol.  V,  pp.  417-428,  June,  1888. 

^See  pp.  169-171,  with  PI.  XVIII. 

'  Compare  with  Mr.  Gilliert's  hypothetic  explanation  of  the  Stansbury  shoie-line  of  Lake  Bonne- 
ville, U.  S.  Geol.  Survey,  Monograph  I,  p.  186. 


596  THE  GLACIAL  LAKE  AGASSIZ. 

At  tlie  time  when  the  last  ice-sheet  retreated,  however,  the  confluent 
waters  of  Devils  and  Stump  lakes  were  raised  to  a  shore-line  which  now 
has  a  slight  ascent  from  west  to  east,  lying  21  to  25  feet  above  the  low 
stage  of  Devils  Lake  in  1889.  This  shore  is  traceable  around  both  lakes, 
passing  above  the  watershed  that  now  divides  them.  At  the  same  height, 
as  shown  by  leveling,  a  well-marked  watercourse  is  found  running  across 
the  present  Avatershed  between  the  west  part  of  Stump  Lake  and  the  Shey- 
enne  River,  in  section  19,  township  151,  range  61.  This  glacial  channel  of 
outflow  has  a  nearly  flat  bottom  150  feet  wide,  and  is  bordered  on  both 
sides  by  moderately  steep  morainic  hills  50  to  75  feet  high. 

While  the  ice  border  was  retreating  across  these  lake  basins  the  inflow 
from  its  melting  produced  a  large  outflowing  stream,  but  there  is  no  proof 
that  any  time  since  the  departure  of  the  ice  has  been  so  humid  as  to  raise 
the  lakes  to  this  channel.  The  heavy  growth  of  timber  which  in  many 
places  borders  the  lakes  extends  across  the  highest  beach  ridge  or  line  of 
erosion  to  the  next  shore,  which,  as  before  noted,  is  the  limit  of  the  forest, 
and  therefore  is  believed  to  have  been  the  lake  margin  since  the  beginning 
of  this  centmy.  Though  the  climate  so  lately  had  during  a  considerable 
term  of  years  more  rainfall  than  now,  it  was  yet  surely  less  than  the  aver- 
age amount  in  the  region  of  the  Laurentiau  lakes  and  in  New  England, 
else  the  levels  of  both  lakes  must  have  been  raised  to  overflowing — that 
is,  to  the  continuous  highest  shore-line  and  channel  of  discharge  southwest 
of  Stump  Lake. 

The  following  are  notes  of  the  elevations  of  these  lakes,  of  their  former 
shore-lines  above  their  present  levels,  and  of  this  outlet.  A  slight  difi'eren- 
tial  uplifting,  like  that  which  gave  to  the  beaches  of  Lake  Agassiz  their 
northward  and  eastward  ascents,  is  shown  by  the  glacial  shore-line,  which 
is  now  level  thi-ough  its  western  1 8  miles  from  Minnewaukan  to  the  city  of 
Devils  Lake,  but  thence  rises  eastward  about  3  feet  in  a  distance  of  16 
miles  to  Jerusalem,  and  1  foot  more  in  the  next  6  miles  southeast  to  the 
channel  of  outlet. 


FLUCTUATIONS  OF  DEVILS  AND  STUMP  LAKES.  597 

Notes  of  leveling  in  the  vicinity  of  Devils  and  Stump  lakes. 

Feet  above 
the  sea. 

Railway  at  passenger  station,  city  of  Devils  Lake 1, 4G4 

Railway  at  passenger  station,  Minnewaukan 1,  461 

Devils  Lake,  surface  of  water  August  8,  1887 1,  431.  6 

Devils  Lake  in  1889 1,  430 

Devils  Lake,  highest  and  lowest  stages  during  the  years  1880  to  1889. .   1,  434-1,  430 

Stump  Lake,  surface  of  water  August  12,  1887 1,  417 

Former  shorelines  of  Devils  Lake  at  Minnewaukan  and  the  city  of  Devils 

Lake    1,  451,  1,  446,  1,  439 

Former  shore-lines  at  Jerusalem  on  Lamoreaux  Bay 1,  454,  1,  446,  1,  439 

Former  shore-lines  of  Stump  Lake 1,  455,  1,  443,  1,  433,  1,  426 

Bottom  of  channel  of  outflow  from  Stump  Lake  to  the  Sheyenne  River 1, 454. 6 

The  elevations  of  the  former  shores  of  Stump  Lake  were  determined 
by  leveling  on  the  northern  slope  of  a  promontory  of  till,  which  was  an 
island  at  the  time  of  the  higher  shore-lines,  rising  to  1,458  feet,  in  the 
east  part  of  section  21,  township  151,  range  61.  Postglacial  deposition  of 
alluvium,  brought  from  slight  ravines  gullied  by  rains  on  the  adjoining 
morainic  hills,  may  have  raised  the  bed  of  the  channel  of  overflow  1  to  3 
feet,  or  possibly  more.  The  outflowing  river,  like  the  River  Warren,  was 
evidently  shallow  during  the  greater  part  of  each  j^ear,  corresponding  to 
the  general  level  of  Devils  and  Stump  lakes,  then  confluent ;  and  while  the 
glacial  melting  was  most  rapid  during  the  summer  months,  this  somewhat 
extensive  body  of  water  and  its  outlet  were  probably  raised  no  more  than 
a  few  feet  above  their  minimum  winter  stage. 

Besides  the  formei'ly  higher  stages  of  these  and  other  neighboring 
lakes,  it  is  also  known  that  they  have  stood  continually  lower  than  now,  at 
least  by  several  feet,  during  a  long  period,  sufficient  for  the  growth  of  lai'ge 
foi'ests  on  the  shores  of  Stump  Lake,  and  of  the  North  and  South  Wash- 
ington lakes  and  Lake  Coe,  in  township  149,  range  63;  for  this  is  proved 
by  submerged  logs  and  stumps,  the  latter  standing  i-ooted  in  the  soil  where 
they  grew.  Many  of  these  logs  and  stumps  have  been  hauled  out  of  the 
southeastern  bay  of  Stump  Lake  by  the  neighboring  farmers  for  use  as 
fuel.  This  prolonged  epoch  of  comparative  desiccation  may  have  coincided 
with  the  yet  more  arid  conditions  in  the  Great  Basin,  which,  as  shown  by 


598  THE  GLACIAL  LAKE  AGASSIZ. 

Russell,  appear  to  have  entirely  dried  up  Pyramid,  Wiunemucca,  and  other 
lakes  of  Nevada  about  three  hundred  years  ago.^  On  the  other  hand,  the 
high  stage  of  De^dls  Lake  before  mentioned  was  near  the  time  of  the  highest 
known  flood  of  the  Red  River,  in  1826,  when  its  water  rose  5  feet  above 
the  surface  where  Winnipeg  is  now  built.  Likewise  it  should  be  noted 
that  the  highest  known  stage  of  the  Laurentian  lakes  was  in  1838,  when 
Lake  Erie  stood  6  feet  above  its  lowest  recorded  stage,  which  was  in  the 
winter  of  1819-20. 

TEMPERATURE. 

Owing  to  the  geographic  position  of  the  basin  of  Lake  Agassiz,  in  the 
central  part  of  a  large  continent  and  nearly  equidistant  between  the  equator 
and  the  north  pole,  the  difference  between  the  mean  temperatures  of  sum- 
mer and  winter  is  great,  the  winters  being  very  cold  and  usuall}'  some 
portions  of  the  summers  very  hot.  The  temperature,  however,  is  mostly 
cool  and  invigorating  tlu'ough  the  six  or  seven  months  in  which  the  land  is 
worked  and  its  harvest  gathered. 

In  summer  there  are  commonly  only  a  few  excessively  hot  days  (80° 
to  100°  F.)  in  a  single  heated  term,  which  is  preceded  and  followed  by 
longer  terms  of  agreeable  coolness,  even  at  midday.  It  is  also  important 
to  note  that,  however  hot  the  days  may  be,  the  nights,  almost  without 
exception,  through  the  whole  summer  are  cool  and  favorable  for  refreshing 
slsep. 

In  winter,  though  the  temperature  is  continuovisly  below  zero  of  the 
Fahrenheit  scale,  even  at  midday,  while  the  sun  shines  brightly,  during  days 
and  occasionalh^  weeks  together,  the  dryness  of  the  air  makes  the  extreme 
cold  (10°  to  40°  below  zero)  no  more  difficult  to  endure  than  a  temperature 
25°  to  50°  higher  with  the  moist  air  of  the  region  about  the  Laurentian  lakes 
and  on  the  Atlantic  coast.  Usually  there  is  no  considerable  thawing  at 
any  time  during  two  or  three  months  of  the  winter.  The  ordinarily  scanty 
snowfall,  which  gives  a  sheet  of  snow  seldom  exceeding  a  foot  in  average 
depth,  is  likely  to  serve  well,  if  not  too  much  drifted,  by  gales  at  the  time 

'Geological  History  of  Lake  Lahontau,  U.   S.  Geol.  Survey,  Monograph  XI,  pp.  223-237,  252. 
Compare  G.  K.  Gilbert's  Lake  Bonneville,  Monograph  I,  p.  258. 


TEMPEEATUEE. 


599 


of  its  fall,  for  sleighing  and  sledding  through  this  whole  period  of  steady 
cold.  This  season,  too,  is  more  sharply  demarked  than  in  most  other  parts 
of  the  United  States.  It  is  begun  by  a  sudden  cold  wave,  generally  dtiring 
the  first  half  of  November,  which  freezes  the  ground  and  stops  the  late 
autumn  work  of  plowing;  and  the  return  of  warmth  in  spring  is  by  a  sud- 
den transition  which  rapidly  melts  away  the  snow  and  soon  thaws  and 
dries  the  land  sufficiently  to  prepare  it  for  the  seeding  of  the  broad  wheat 
fields. 

The  foll'owing  table  shows  the  mean  temperatures  at  the  six  stations 
before  noted.  In  the  United  States  they  were  computed  from  the  daily 
extremes  of  temperature  during  a  period  of  nine  years  preceding  the  end 
of  1888.  At  Winnipeg,  Manitoba,  the  average  is  drawn  from  observations 
begun  in  1871  and  extending  through  fifteen  years. 

Normal  temperature,  in  degrees  Fahrenheit,  for  each  month  and  for  the  whole  year. 


Stations. 

Janu- 
ary. 

Febru- 
ary. 

March. 

April. 

May. 

June. 

July. 

Au- 
gust. 

Septem- 

Octo- 
ber. 

Novem- 
ber. 

Decem- 
ber. 

Tear. 

7.9 

6 
-4.8 
-9.6 
-5.7 

1.4 

15.6 
12.4 
4.2 
-0.6 
—0.1 
9.6 

27.4 
21.9 
18.6 
13.2 
11.5 
20.8 

46.2 

37.7 

40 

36.2 

33.7 

41.4 

58.6 
'48.6 
63.8 
52 
52.1 
55.7 

68.1 

58 

64.3 

62.2 

61.5 

65 

72.4 

66 

67.8 

65.2 

65.8 

69.5 

69.6 
64.2 
65.3 
62.8 
63.6 
67.2 

60.1 
56.1 
56.2 

53.4 
51.7 
57 

48 

45.2 

43.1 

40 

39 

43.9 

31.3 

29.4 
24.8 
20.6 
16.7 
27.4 

18 
16.7 

9.7 

5 

2 
13.8 

43.6 

38.5 

36.9 

33.4 

33.2 

39.4 

Mean  for  entire  dis- 

-0.8 

6.8 

18.9 

39.2 

53.5 

63.2 

67.8 

65.4 

55.7 

43.2 

25 

10.9 

37.5 

Ice  on  the  Red  River  closed  the  season  of  navigation  at  Moorhead 
and  Fargo  in  the  years  1881  to  1888  at  dates  which  range  from  the  11th 
to  the  25th  of  November;  and  navigation  was  opened,  with  the  breaking 
up  and  departure  of  the  ice,  at  dates  from  the  12th  to  the  24th  of  April. 
Throughout  the  years  1889  and  1890  navigation  was  suspended  because  of 
the  low  stage  of  water. 

The  first  severe  frosts,  destroying  tender  vegetation,  occun-ed  at  Moor- 
head and  Fargo  in  the  years  1881  to  1890  at  dates  from  August  25  to 
September  20;  and  the  last  severe  frost  there  in  spring  during  the  same 
years  ranged  from  May  2  to  June  8.  At  St.  Vincent  these  dates  for  the 
first  were  from  August  4  to  September  20,  and  for  the  last  from  April  29 
to  June  8. 


600  THE  GLACIAL  LAKE  AGASSIZ. 

WINDS. 

The  nearly  level  vast  praiiies  are  fully  exposed  to  all  currents  of  the 
ah-,  and  during  the  most  windy  months,  which  are  in  the  spring  and  autumn, 
they  seem  very  bleak  to  one  who  has  previously  lived  only  in  districts 
where  the  surface  mostly  receives  a  partial  shelter  from  the  force  of  winds 
by  the  undulations  of  hills  and  vales  and  by  the  presence  of  forests  and 
trees  cultivated  for  ornament  and  shade.  The  movements  of  the  atmos- 
phere on  the  prairie  district  of  Lake  Agassiz  do  not  appear,  however,  to 
exceed  in  their  aggregate  amount  those  on  its  wooded  district,  or  on  the 
basins  of  the  Laurentian  lakes,  or  on  the  Atlantic  seaboard.  Exposed 
places  throughout  these  areas,  as  the  tops  of  hills,  are  quite  as  severely 
swept  by  gales  as  the  prairies,  where  they  are  so  much  more  observed 
in  the  common  experience  of  the  people.  One  of  the  most  desirable 
improvements  of  the  prairie  homestead  is  the  cultivation  of  rows  of  trees, 
called  wind-breaks,  about  the  buildings. 

Winds,  usually  light,  but  on  many  days  heavj-,  are  moving  almost 
continually  over  this  area,  with  variations  in  their  direction  to  every  point 
of  the  compass.  From  the  hourly  records  of  the  velocity  of  the  winds  as 
measured  by  self-registering  anemometers  during  the  seven  years  from  1883 
to  1889,  inclusive,  their  mean  velocity  for  this  whole  period  was  6.58  miles 
per  hour  at  St.  Paul,  7.28  miles  at  Duluth,  8.81  miles  at  St.  Vincent,  and 
8.39  miles  at  Bismarck. 

With  these  means  it  will  be  instructive  to  compare  the  records  of 
several  stations  in  other  parts  of  the  country  during  the  same  time,  which 
show  for  Boston,  Mass.,  a  i«ean  velocity  of  11.18  miles  per  hour;  New 
York  City,  9.30  miles;  Washington,  D.  C,  5.39  miles;  Savannah,  7.12 
miles;  Chicago,  9.01  miles;  Cincinnati,  6.55  miles;  St.  Louis,  10.56  miles; 
New  Orleans,  7. 26  miles ;  Omaha,  8.05  miles ;  Denver,  6.99  miles ;  Salt 
Lake  City,  5.18  miles;  Portland,  Oreg.,  4.94  miles;  San  Francisco,  8.94 
miles;  and  San  Diego,  Cal.,  5.61  miles.  Among  sixty-six  stations  of  the 
United  States  Signal  Service  thus  tabulated,  the  maximum  mean  velocity 
of  the  wind  is  at  Dodge  City,  Kans.,  11.48  miles  per  hour,  and  the  mmi- 
mum  is  at  Lynchburg,  Va.,  3.76  miles.      The  least  windy  station  of  the 


FLORA  OF  THE  RED  RIVER  BASIN.  601 

United  States,  however,  appears  to  he  Pha3nix,  Ariz.,  where  the  records 
of  the  years  1879  to  1881,  inclusive,  showed  a  mean  velocity  of  only  2.37 
miles. 

FLORA    OF    TnF    BASIN    OF    THE    REI>    RIVER    OF    THE    NORTH. 

Upon  every  portion  of  the  land  area  of  the  g'lohe,  the  flora,  or  assem- 
blage of  species  constituting  its  mantle  of  vegetation,  is  a  very  sensitive 
resfister  of  its  a^ffreffate  climatic  conditions  and  of  the  value  of  its  soil  for 
agriculture.  In  almost  an  equal  degree,  also,  the  fauna,  or  representation 
of  animal  life,  testifies  what  the  capabilities  of  the  country  will  be  for 
pasturage  and  stock  raising,  and  what  crops  will  be  successfully  cultivated 
by  the  farmer,  even  before  the  coming  of  the  axman  to  fell  the  forest  and 
of  the  plowman  to  draw  the  first  furrow  on  the  prairie.  The  vast  herds  of 
liuff'alo''  and  the  frequent  droves  of  antelope  and  elk  which  roamed  over 
this  district  previous  to  the  advent  of  the  white  man  were  a  prognostication 
of  the  present  ranchman's  wealth  of  cattle,  horses,  and  sheep,  feeding  in 
the  valleys  and  on  the  plains  from  which  the  native  tall  game  and  the  abo- 
riginal huntsman  have  so  recently  vanished.  The  nutritious  and  abundant 
grasses  and  other  herbage  on  which  tlie  wild  herds  fed  are  now  succeeded 
by  luxurant  fields  of  grain,  or,  growing  in  the  yet  unbroken  sward,  they 
now  fatten  the  lieef,  rear  the  broncho  and  thoroiighbred  horses,  and  produce 
the  wool,  which  are  exported  to  Chicago  and  more  eastern  markets. 

Though  no  sti'ongly  defined  line  of  division  can  be  drawn  between 
different  portions  of  tlie  flora  and  fauna  of  the  country  from  the  Atlantic  to 
the  Rocky  Mountains  and  from  the  Gulf  of  Mexico  to  the  Arctic  Sea,  it  is 

'The  early  immigrants  fouud  tlie  bones  of  buffaloes  scattered  here  and  there  throughout  the 
whole  prairie  region.  On  account  of  their  commercial  value  for  sugar  refining  and  for  the  manufac- 
ture of  superphosphate,  these  boues  were  collected  and  sold  at  the  railway  stations  <lnring  the  first 
two  or  three  years  after  the  railway  was  built  into  any  new  part  of  the  country.  A  heaji  of  buffalo 
bones  which  I  saw  beside  the  railway  awaiting  shiximeut  at  Langdon,  N.  Dak.,  in  August,  1889,  meas- 
ured 100  feet  by  20  feet  in  area,  with  an  average  height  of  4  feet,  representing  probably  two  or  three 
thousand  anim.als.  During  the  same  m(mth  I  saw  a  much  larger  pile  of  bones  at  Minot,  in  the  same 
state,  its  contents  being  estimated  as  ec^ual  to  200  feet  by  30  feet  by  4  feet.  Tlie  dealer  informed  me 
that  the  weight  of  this  pile  was  about  600  tons,  and  that  during  the  preceding  part  of  the  year  lie 
had  purchased  and  already  shipped  some  1,200  tons,  the  average  price  paiil  being  $8  per  ton.  1  )uring 
the  one  forenoon  when  I  was  there,  ten  or  more  wagonloads  of  bones  were  brought  in  by  the  farmers 
from  the  region  around.  Probably  nearly  all  that  could  be  found  in  the  vicinity  were  collected  during 
that  year.     (Compare  page  139,  and  Geology  of  Minnesota,  Vol.  II,  p.  516.) 


602  THE  GLACIAL  LAKE  AGASSIZ. 

nevertheless  true  that  great  contrasts  exist  between  the  eastern  region,  with 
its  plentiful  rainfall,  and  the  dry  western  plains,  as  also  between  the  almost 
tropical  southern  margin  of  the  United  States  and  the  tundras  Ijeneath  the 
Arctic  Circle.  In  traveling  from  the  once  wholly  forest-covered  country 
of  the  eastern  States  across  the  prairies  to  the  far  western  plains,  bearing 
cacti  and  sagebrush,  there  is  observed  a  gradual  change  in  the  flora,  until 
a  very  large  proportion  of  the  eastern  species  is  left  behind,  and  then*  places 
are  taken  by  othei's  capable  of  enduring  more  arid  conditions.  Likewise 
in  going  from  St.  Augustine  or  New  Oideans  to  Chicago,  St.  Paul,  Wimiipeg, 
and  Hudson  Bay  and  Strait,  the  ^Jalmettoes,  the  evergreen  live  oak,  bald 
cypress,  southern  pines,  and  the  festooned  Tillandsia  or  "Spanish  moss," 
are  left  in  passing  from  the  southern  to  the  northern  States ;  and  instead  we 
find  in  the  region  of  the  Laurentian  lakes  the  bur  or  mossy-cup  oak,  the 
canoe  and  yellow  birches,  the  tamarack  or  American  larch,  the  black  spruce, 
balsam  fir,  and  the  white,  red,  and  Banksian  pines,  while  farther  north  the 
white  spruce,  beginning  as  a  small  tree  in  northern  New  England  and  on 
Lake  Superior,  attains  a  majestic  growth  on  the  lower  ]\[ackenzie  in  a  more 
northern  latitude  than  a  large  part  of  the  moss-covered  Barren  Grounds 
which  reach  thence  eastward  to  the  northern  part  of  Hudson  Bay  and 
Labrador.  Thus,  although  no  grand  topographic  barrier,  like  a  high  moun- 
tain range,  impassable  to  species  of  the  lowlands,  divides  this  great  region, 
the  transition  from  a  humid  to  an  arid  climate  in  passing  westward,  and  the 
exchange  of  tropical  warmth  for  polar  cold  in  the  journey  from  south  to 
north,  are  accompanied  by  gradual  changes  of  the  flora  by  which  in  the 
aggregate  its  aspect  is  almost  completelv  transformed. 

In  the  central  part  of  this  large  area,  the  basin  of  the  Red  River  of 
the  North,  with  my  geologic  exploration  during  a  half  dozen  summers,  I 
have  given  careful  attention  also  to  the  geographic  limits  and  relative 
abundance  of  the  species  making  iip  the  flora.  It  has  been  interesting  to 
find  there  the  intermingling  and  the  Ijoundaries  of  species  whose  23rincipal 
homes  or  geographic  range  lie  respectively  in  the  directions  of  the  four 
cardinal  points,  east  and  west,  south  and  north. 


GEOGRAPHIC  LIMITS  OF  TREES  AND  SHRUBS.  603 


FOREST  TREES  AND  SHRUBS. 


Many  species  of  trees  which  together  constitute  a  large  part  of  the 
eastern  forests  extend  to  the  Red  River  basin,  reaching  there  the  western 
or  northwestern  boundary  of  their  range.  Among  these  are  the  basswood, 
sugar  maple,  river  maple,  and  red  maple,  the  three  species  of  white,  red, 
and  black  ash,  the  red  or  slippery  elm,  and  the  rock  or  cork  elm,  the  but- 
ternut, the  white,  bur,  and  black  oaks,  iron  wood  [Ostrya  virginica  Willd.), 
the  American  hornbeam  (Carpinus  caroliniana  Walt.),  the  yellow  birch,  the 
large-toothed  poplar,  white  and  red  pine,  arbor-vitge,  and  the  red  cedar 
or  savin.  A  few  species  of  far  northern  range  find  in  this  district  their 
southern  or  southwestern  limit,  namely,  our  two  species  of  mountain  ash, 
the  balsam  poplar,  Banksian  or  jack  pine,  the  black  and  the  white  spruca, 
balsam  fir,  and  tamarack. 

Some  of  the  eastern  shrubs  which  make  the  undergrowth  of  our  forests 
also  attain  here  their  western  limits;  but  a  larger  proportion  of  these  than 
of  the  forest  trees  continues  west  along  the  stream  courses  to  the  Saskatch- 
ewan region,  the  upper  Missouri,  and  the  Black  Hills.  Among  the  shrubs 
that  reach  to  the  borders  of  the  Red  River  basin,  but  not  farther  westward, 
or  at  least  southwestward,  are  the  black  alder  or  winterberry,  the  moun- 
tain holly,  the  staghorn  sumach,  the  hardback,  the  huckleberry,  the  dwarf 
blueberry  and  the  tall  or  swamp  blueberry,  leatherwood,  and  sweet  fern. 
Shrubs  and  woody  climbers  that  have  their  northern  or  northwestern 
boundary  in  this  basin  include  the  prickly  ash,  staff  tree  or  shrubby  bittei-- 
sweet,  frost  gra2:)e,  Virginian  creeper,  and  the  four  species  of  round-leaved, 
silky,  panicled,  and  alternate-leaved  cornel.  On  the  other  hand,  shrubs  of 
the  north  which  reach  their  southern  or  southwestern  limits  in  the  Red 
River  basin  include  the  mountain  maple,  the  few-flowered  viburnum  and 
withe-rod,  several  species  of  honeysuckle,  the  Canada  blueberry,  the  cow- 
berry, Andromeda polifolia  L.,  Kalmia  glauca  Ait,  Labrador  tea,  the  Canadian 
shepherdia,  sweet  gale,  the  dwarf  birch,  green  or  mountain  alder,  beaked 
hazel-nut,  Salix  balsamifera  Barratt,  and  S.  myrtilloides  L.,  var.  pedicellaris 
Anders.,  black  crowberry,  creeping  savin,  and  the  American  yew  or  ground 
hemlock. 


604  THE  GLACIAL  LAKE  AGASSIZ. 

No  tree  of  exclusivel}'  western  range  extends  east  to  the  Rect  River 
basin,  and  it  has  only  a  few  western  species  of  shrubs,  of  which  the  most 
noteworthy  are  the  alder-leaved  Juneberry  or  service  berry  (in  Manitoba 
commonly  called  "saskatoon"),  the  silverberry,  and  the  buifalo-berry.  To 
these  are  also  to  be  added  the  shrubby  (Enothera  alhicaulis  Nutt.,  which 
occurs  chiefly  as  an  immigrant  weed,  and  the  small-leaved  false  indigo, 
which  abounds  on  moist  portions  of  the  prairie.  The  silverberry  (usually 
called  "wolf  willow"  in  the  Red  River  Valley)  is  common  or  abundant  from 
Clifford,  N.  Dak.,  and  from  Ada,  Minn.,  northward,  forming  patches  10  to 
20  rods  long  on  the  prairie,  growing  only  about  2  feet  high  and  fruiting 
plentifully,  but  in  thickets  becoming  5  to  10  feet  high.  Its  silvery  whitish 
foliage  and  fruit  make  this  shrub  a  very  conspicuous  and  characteristic 
element  of  tlie  Red  River  flora. 

The  single  species  of  true  sagebrush  belonging  to  this  basin  (^Artemisia 
cana  Pursh)  extends  east  in  North  Dakota  to  the  Heart,  Mound,  6  miles 
northwest  of  Walhalla,  or  35  miles  west  of  the  Red  River  at  Pembina,  and 
to  a  hill  close  west  of  the  Sheyenne  River,  about  8  miles  south  of  Valley 
City,  growing  in  both  places  on  outcrops  of  the  Fort  Pierre  shale.  It 
attains  a  height  of  1  to  3  feet,  and  the  tough  wood  of  its  base  is  1  to  1.J 
inches  in  diameter.  Artemisia  frigida  Willd.,  called  "pasture  sagebrush" 
by  Macoixn,  is  abundant  throughout  a  wide  area  westward,  extending  east 
locally  to  "the  ridge"  east  of  Emerson,  Manitoba,  the  Falls  of  St.  Anthony, 
and  Lake  Pepin. 

Causes  of  limitation  of  the  forest. — The  boundary  between  the  forest  and 
the  prairie,  shown  by  PI.  XXXVIII,  and  the  similarity  of  the  two  regions 
in  their  topographic  features  and  drift  deposits,  have  been  noted  in  Chapter 
II  (pp.  44-46).  The  usually  abrupt  transition  from  the  timbered  to  the 
prairie  country  and  the  general  absence  of  trees  and  shrubs  in  the  prairie 
region  have  been  often  attributed  tt)  the  effect  of  fires.  Through  many 
centuries  fires  have  almost  annualh'  swept  over  these  areas,  generally 
destroying  all  seedling  trees  and  shrubs,  and  sometimes  extending  the  border 
of  the  prairie  by  adding  tracts  from  which  the  forest  had  been  burned. 
Late  in  autumn  and  again  in  the  spring  the  dead  grass  of  the  prairie  burns 
very  rapidly,  so  that  a  fire  within  a  few  days  sometimes  spreads  50  or  100 


U.S. GEOLOGICAL  SURVEY. 


MONOGRAPH    XXV.    PL.XXXVIH. 


MAI^  OF  THE  HOIT'rHI'lHN  l^OUTION  OF  L.VlvK  xVOx'vSSlZ.SHOWlNdiVRKAS  UK  K)Rb:ST  AND  PliAIlilK. 

Scale,  about  VI  miles  to  aiiiudi. 


Forest  Ai-ea,aiul  bi'lts  ami  palilies  ol'  'rinilieT-oii  sUvams  uiul  hikes  L 


Praii'ie  L. 


CAUSES  OF  LIMITATION  OF  THE  FOEEST.  605 

miles.  The  groves  that  remain  in  the  prairie  region  are  usually  in  a  more 
or  less  sheltered  position,  being-  on  the  borders  of  lakes  and  streams,  and 
sometimes  nearly  surrounded  by  them,  while  areas  that  can  not  be  reached 
by  fires,  as  islands,  are  almost  always  wooded.  If  fires  should  fail  to  over- 
run the  prairies  in  the  future,  it  can  hardly  be  doubted  that  much  of  that 
area  would  gradually  and  slowly  be  changed  to  forest. 

Yet  it  does  not  appear  that  fires  in  the  western  portion  of  our  great 
forest  region  are  more  frequent  or  destructive  than  eastward;  and  our 
inquiry  must  go  back  a  step  further  to  ask  why  fires  east  of  the  Appala- 
chian Mountains  had  nowhere  exterminated  the  forest,  while  so  extensive 
areas  of  prauie  have  been  guarded  and  maintained,  though  not  apparently 
produced,  by  prairie  fires  here.  Among  the  conditions  which  liave  led  to 
this  difterence  we  must  undoubtedly  place  first  the  greater  amount  and 
somewhat  more  equable  distribution  throughout  the  year  of  raiu  in  the 
Eastern  States.-^ 

Evidence  that  an  increase  of  moisture  in  the  ground  suffices  to  produce 
a  heavy  growth  of  forest  trees  in  a  principally  prairie  region,  even  without 
protection  from  the  incursions  of  prairie  fires,  is  afforded  by  the  bluffs  of 
the  opposite  sides  of  the  valley  of  the  Minnesota  River,  which  was  the 
course  of  the  River  Warren,  outflowing  from  Lake  Agassiz.  Timber  is 
found  in  a  nearly  continuous  though  often  very  narrow  strip  bordering  this 
stream  through  almost  its  entire  course,  but  generally  leaving  much  of  the 
bottom-land  treeless.  The  bluff's  on  the  northeast  side  of  the  river  have 
for  the  most  part  only  thin  and  scanty  groves  or  scattered  trees.  The 
southwestern  bluff's,  on  the  contrary,  are  heavily  wooded  through  Blue 
Earth  and  Brown  counties,  excepting-  2  or  3  miles  at  New  Ulm.  They 
also  are  frequently  well  timbered  in  Redwood  and  Yellow  Medicine  coun- 
ties, but  in  Lac  qui  Parle  County  they  are  mostly  treeless  and  have  only 

'  The  dependence  of  forests  on  a  greater  supply  of  rainfall  than  is  needed  by  the  grasses  and  other 
herbaceous  vegetation  of  the  prairies  is  ably  stated  by  Prof.  James  D.  Dana,  "On  the  origin  of 
prairies,"  Am.  Jour.  Sci.  (2),  A^ol.  XL,  1865,  pp.  293-304;  and  by  Dr.  George  M.  Dawson,  with  discus- 
sion of  prairie  fires  and  the  benefits  to  be  derived  from  tree  culture.  Geology  and  Resources  of  the 
Region  in  the  Vicinity  of  the  Forty-ninth  Parallel,  1875,  pp.  311-324.  Eifects  of  drought  and  of  cold 
to  set  limits  to  forests,  and,  on  the  other  hand,  extension  of  prairies  into  formerly  timbered  areas 
through  the  agency  of  annual  fires,  kindled  by  the  Indians  for  the  puri>ose  of  driving  the  game  toward 
the  hunters  or  providing  a  better  growth  of  grass  on  which  butt'aloes  and  deer  wouhl  feed,  are  noted 
by  Prof.  N.  S.  Shaler,  Aspects  of  the  Earth,  1889,  pp.  282-290.  Other  views  which  hud  been  advanced 
by  Whitney,  A.  Winchell,  and  Lesquereux,  previous  to  Dana's  paper  on  this  subject,  seem  untenable. 


606  THE  GLACIAL  LAKE  AGASSIZ. 

occasioual  groves.  The  greater  abundance  of  timber  on  the  southwestern 
bluflfs  appears  to  be  due  to  their  being  less  exposed  to  the  sun,  and  there- 
fore more  moist,  than  the  bluffs  at  the  opposite  side  of  the  valley.  Above 
Montevideo  the  timber  is  mainly  restricted  to  a  narrow  belt  beside  the  river 
and  to  tributary  valleys  and  ravines. 

PRAIKIE    GRASSES   AND    FLOWERS. 

Among  the  fifteen  hundi-ed,  more  or  less,  indigenous  species  of  herba- 
ceous jjlants  inhabiting  the  Red  River  basin,  probably  half  are  deserving  of 
note  for  attaining  their  geographic  limit  upon  this  area,  or  at  least  the 
limit  of  their  abundant  or  frequent  occurrence.  But  thorough  and  detailed 
botanic  exploration  of  all  the  great  interior  region  of  our  continent  west- 
ward to  the  Rocky  Mountains  and  far  northward  will  be  requisite  before 
we  can  speak  with  certainty  concerning  many  of  the  less  conspicuous 
species  of  our  flora.  We  may  here  notice  briefly  some  of  those  plants 
whose  geographic  range  is  best  known,  especially  such  as  are  useful  for 
pasturage  and  hay. 

In  general,  the  flora  of  the  prairie  area  of  Lake  Agassiz  is  mostly  made 
up  of  species  that  are  familiar  to  residents  of  the  Eastern  and  Southern 
States,  occurring  also  commonly  or  abundantly  there;  but  many  of  these 
plants  reach  their  western  and  northern  limits  along  the  Red  River  of  the 
North. 

On  the  other  hand,  seventy-six  species^  of  northern  range,  some  of 
them  plentiful  beneath  the  Arctic  Circle,  are  known  to  extend  south  of  the 
forty-ninth  parallel  in  the  Red  liiver  Valley,  or  on  the  east  to  the  Lake  of 
the  Woods  or  into  northern  Miimesota,  but  not  to  the  southern  end  of  this 
valley  at  Lake  Traverse.  This  northern  element  of  the  Red  River  flora 
includes  thirteen  species  of  Carex,  and  nine  grasses,  the  latter  being  De- 
yeuxia  langsdorffii  Kunth,  Trisefum  suhspicatum  Beauv.,  var.  inolle  Gray, 
Danthonia  intermedia  Vasey,  Poa  alpina  L.,  P.  laxa   Hsenke,   Agropyrum 

'Lists  of  these  species  and  of  the  western  species  extending  into  this  district,  also  a  list  of  the 
weeds  (troublesome  to  the  farmer)  observed  in  the  district,  both  indigenous  and  introduced,  with  notes 
of  their  range  and  relative  abundance,  are  given  in  my  paper,  "Geographic  limits  of  species  of 
plants  in  the  basin  of  the  Red  River  of  the  North,"  Proc,  Boston  Soc.  of  Nat.  Hist.,  Vol.  XXV,  1890, 
pp.  UO-172. 


PRAIRIE  GRASSES.  607 

dasystachyum  Vasey,  A.  tenerum  Vasey,  Elynius  sihiricus  L.,  var.  americanus 
Watson,  and  E.  mollis  Trin. 

Another  list  of  one  hundred  and  two  species  comprises  phxnts  which 
are  known  to  attain  their  eastern  limits  within  the  Red  River  basin,  being 
common  thence  westward  on  the  plains  and  often  in  the  Rocky  Mountains 
and  to  the  Pacific.  In  this  list  are  twenty  Compositaj,  most  of  them 
abundant  and  showy;  four  species  of  Carex;  and  twelve  grasses,  namely, 
Bechnannia  erucceformis  Host,  var.  uniflora  Scribner,  Stipa  spartea  Trin.,  S. 
viridula  Trin.,  Sx)orobolus  cuspidatus  Torr.,  Avena  pratensis  L.,  var.  americana 
Scribner,  Schedonnardus  texaims  Steud.,  Bouteloua  oligostadiya  Torr.,  Distich- 
lis  maritima  Raf.,  var.  strida  Thurber,  Poa  tenuifolia  Nutt.,  Festuca  scahrella 
Tori'.,  Agropyriim  glaucum  R.  &  S.,  var.  occidentale  V.  &  S.,  and  Elymus 
sitanion  Schultes. 

The  most  plentiful  and  valuable  grasses  in  this  northeastern  part  of 
the  great  prairie  region  of  the  continent  are  as  follows,  with  notes  of  their 
habit  of  growth  and  comparative  importance: 

Spartina  cynosuroides  Willd.,  the  iirevailiug  and  ofteu  the  only  grass  of  slough.s 
(which  is  the  term  commonly  applied  to  miry  depressions  of  the  prairie),  making  good 
hay;  also  largely  used  as  fuel  by  immigrants  in  many  districts  remote  from  timber 
and  railways,  and  as  thatch  by  Mennonite  colonists  in  Manitoba. 

Bechnannia  erucceformis  Host,  var.  uniflora  Scribner,  frequent  or  common  on  wet 
ground,  where  water  stands  a  part  of  the  year,  from  Port  Arthur,  Lake  Superior,  to 
the  Rocky  Mountains,  extending  northeast  to  Hudson  Bay  and  Lake  Mistassini. 

Panicum  capillare  L.,  common  along  streams,  and  in  sandy  cultivated  fields. 

Panicum  virgaUim  L.,  frequent,  often  abundant,  on  somewhat  moist  portions  of 
the  prairie,  especially  in  southwestern  Minnesota  and  South  Dakota. 

Andropogon  furcatus  Muhl.,  abundant  on  rather  dry  tracts  iu  South  and  North 
Dakota,  where  it  is  usually  called  "blue  joint,"  and  is  highly  esteemed  for  hay;  less 
common  in  Manitoba;  whitish  and  glaucous,  not  abundant,  among  the  sand  daues  of 
the  Sheyenne  delta  of  Lake  Agassiz. 

Andropogon  scoparius  Michx.,  abundant,  occup3ring  drier  land  than  the  last. 

Chrysopogon  nutans  Benth.,  common  or  frequent  in  the  Dakotas;  less  so  farther 
north;  much  cut  for  hay,  with  Andropogon  furcatus  and  Panicum  virgatum. 

Phalaris  arundinacea  L.,  abundant  in  marshes. 

Hierochloe  borealis  R.  &  S.,  very  common  on  moist  ground  and  along  rivers  and 
lakes  throughout  this  northern  ijrairie  region. 


608  THE  GLACIAL  LAKE  AGASSIZ. 

Stipa  spartea  Trin.,  deservedly  named  "porcupine  grass,"  but  more  commonly 
called  "wild  oats"  in  Minnesota  and  the  Dakotas;  abundant  ou  the  dry  prairie, 
especially  in  South  Dakota. 

Stipa  viridula  Trin.,  extending  east,  on  sandy  alluvial  soil  of  bottom-lands,  to 
the  Eed  River ;  also  common  westward  on  the  general  ijrairie. 

Muhlenbergia  glomerata  Trin.  (chiefly  the  var.  ramosa  Vasey),  plentiful  on  moist 
land;  ft'equently  persisting  as  a  weed  in  wheat  fields  and  other  cultivated  ground. 

Sporoholus  cuspidatus  Torr.,  common  on  dry  j^ortions  of  the  prairie  iu  the  Dakotas, 
Manitoba,  and  Assiniboia. 

Sporoholus  hetcrolepis  Gray,  also  plentiful  from  Nebraska  to  northwestern 
Manitoba. 

Agrostis  alba  L.,  var,  vulgaris  Thurber,  indigenous  and  common  on  moist  land, 
especially  northward. 

Agrostis  scabra  Willd.,  abundant  along  rivers,  so  that  in  late  summer  the  wheel 
ruts  of  roads  are  often  filled  with  its  dead  panicles,  broken  oif  and  blown  thither  by 
the  wind. 

Deyeuxia  canadensis  Hook.  f.  (Calamagrostis  canadensis  Beauv.),  abundant  on  wet 
meadows  bordering  streams,  especially  in  the  forest  region. 

Deyeuxia  neglecta  Kunth  (Calamagrostis  stricta  Trin.),  plentiful  on  similar  ground 
throughout  the  prairie  region  west  of  Winnipeg. 

Ammopliila  longifolia  Benth.  {Calamagrostis  longifolia  Hook.),  which  binds  the 
sand  dunes  along  the  south  shore  of  Lake  Michigan,  is  generally  abundant  on  sandy 
ridges  through  all  the  prairie  region  from  the  Red  River  west  to  the  Rocky  Mountains. 

Arena  pratensis  L.,  var.  americana  Scribner,  common  from  Portage  la  Prairie 
westward. 

Banthonia  intermedia  Vasey,  common  from  the  Red  River  to  the  sources  of  the 
Qu'Appelle;  also  found  at  the  east  in  Anticosti  and  Gaspe,  extending  west  to  Van- 
couver Island. 

Bouteloua  oligostachya  Torr.,  the  most  valuable  and  widely  spread  of  the  "buf- 
falo grasses,"  observed  as  the  main  species  of  grass  on  large  tracts  of  the  prairie 
between  Devils  Lake  and  the  Souris  River;  described  by  Vasey  and  Havard  as  the 
commonest  species  on  the  great  plains,  surpassing  all  others  in  its  importance  as 
pasturage  for  stock  of  all  kinds,  even  in  winter,  when  its  dried  tufts  or  bunches  still 
retain  their  nutritive  quality. 

Phragmites  communis  Trin.,  abundant,  often  10  to  15  feet  high,  in  the  edges  of 
lakes.  A  prostrate  stem  20  feet  long,  rooting  at  the  joints,  was  observed  at  Red  Lake, 
Minnesota. 

Kceleria  cristata  Pers.,  very  abundant  on  the  drier  portions  of  the  country, 
affording  good  pasturage;  estimated  by  Lieberg  as  constituting  fully  half  of  the 
entire  growth  of  grass  along  the  Northern  Pacific  Railroad  between  the  James  and 
Yellowstone  rivers. 


PEAIKIE  GllASSES  AND  FLOWERS.  609 

Distichlls  maritima  liaf.,  var.  stricta  Tliuiber,  very  abiuulaiit  on  the  borders  of 
saline  and  alkaline  marshes. 

Poa  tenuifoUa  Nutt.,  one  of  the  much-prized  "bunch  grasses,"  common  from 
Brandon  westward  to  the  Eocky  Mountains,  and  the  most  important  pasture  grass  of 
British  Columbia,  Vancouver  Island,  and  southward. 

Poa  nemoraUs  L.,  forming  much  of  the  pasture  northward. 

Poa  serotina  Ehrh.,  x)lentiful  in  swampy  places  on  lakes  and  rivers. 

Poa  pratcnsis  h.,  the.  famous  "blue  grass"  of  Kentucky,  indigenous  and  abun- 
dant, rapidly  taking  the  place  of  other  species  westward,  and  destined,  according  to 
Macoun,  to  be  the  chief  pasture  grass  of  tliis  region. 

Glyceria  dista^is  Wahl.,  var.  airoides  Vasey,  abundant  lu  saline  marshes  from 
Winnipeg  westward. 

Festuca  scabrella  Torr.,  a  valuable  "bunch  grass,"  abundant  at  Brandon  and 
westward  to  the  mountains. 

Bromus  Icalmii  Gray,  abundant  northward. 

Agropyrum  glaucwm  E.  &  S.,  var.  occidentale  V.  &  S.,  common  on  moist  land, 
especially  where  the  soil  is  somewhat  saline  and  alkaline;  in  Montana,  according  to 
Scribuer,  the  most  highly  valued  of  the  native  grasses  for  hay. 

Agropyrum  tenerum  Vasey,  abundant,  with  the  preceding,  from  Winnipeg  to 
Edmonton  and  southward;  one  of  the  best  grasses  for  hay.  Dr.  Vasey  remarks 
that  in  southwestern  Minnesota  and  South  Dakota,  wherever  the  ground  has  been 
broken  and  not  cultivated,  Agropyrum  glaucum  and  A.  tenerum  Iiave  commonly  taken 
possession. 

Agropyrum  caninum  E.  &  S.,  plentiful  in  the  northern  prairie  region,  fro'u  Win- 
nipeg to  Edmonton.    . 

Hordeum  jubatumlj.,  a,  worthless  species,  well  named  "squirrel-tail  grass"  and 
"tickle  grass;"  very  abundant  by  roadsides  and  on  slightly  saline,  moist  land. 

Ulymus  canadensis  L.,  a  conspicuous  species,  common  on  the  banks  and  blufl's  of 
rivers. 

Besides  the  grasses,  the  prairies  bear  multitudes  of  native  flowers  of 
showy  red,  purple,  blue,  yellow,  and  orange  hues,  and  pure  white,  which 
bloom  from  eai'ly  spring  till  the  severe  frosts  of  autumn.  Earliest  of  all  is 
the  pasque  flower,  named  for  its  blooming  at  Easter,  common  over  all  the 
prairie  region.  With  this,  or  later  in  the  spring,  are  other  species  of  wind- 
flowers,  the  wild  columbine,  indigenous  buttercups,  violets,  and  many  more. 

During  the  summer  the  prairies  are  decked  with  species  of  larkspur, 
Psoralea,  Amorpha,  Petalostemon,  Astragalus,  Oxytropis,  Vicia,  Lathyrus, 
Geum,  rose,  evening  primrose,  many  Composita3,  nearly  all  conspicuous 
MON  XXV 39 


610  THE  GLACIAL  LAKE  AGASSIZ. 

by  their  flowers,  the  harebell,  gentian,  phlox,  Peutstemon,  Gerardia,  Ortho- 
carpus,  Pycnanthemum,  Mouarcla,  Spiranthes,  Sisyrinchium,  Uvularia, 
Sniilacina,  lily,  wild  onion,  spiderwort,  etc.  Often  I  have  seen  large  tracts 
of  the  natural  praii'ie  yellow  with  sunflowers  or  golden-rod;  other  areas 
purple  with  Petalostemon,  Liatris,  or  Gerardia,  or  blue  with  asters;  and 
still  others  white  with  the  profusely  flowering  Galium  boreale  L.  Several 
yellow-flowered  species  of  the  Compositas,  blooming-  in  the  middle  and 
later  portions  of  summer,  resemble  each  other  by  growing  frequently  in 
clumps  or  bunches,  as  the  Grindelia,  Aplopappus,  Cluysopsis,  and  Gutier- 
rezia  in  the  list  of  western  plduts,  here  noted  in  the  declining  order  of  their 
height. 

Numerous  species  of  plants  prefer  the  sandy  beaches  of  Lake  Agassiz 
and  grow  there  in  greater  abundance  and  luxuriance  than  elsewhere,  among 
these  being  the  pasque  flower,  Psoralea  argophylla  Pursh,  and  P.  esculenta 
Pursh,  two  varieties  of  Potentilla  pennsylvanica  L.,  Bosa  arkansana  Porter, 
Liatris  punctata  Hook.,  Clirysopsis  villosa  Nutt.,  Lepachys  columnaris  Torr.  and 
Gray,  Gaillardia  aristata  Pursh,  Lilium  pliiladelpliicum  L.,  and  Ammopliila 
longifolia  Benth.  Near  Arden,  Manitoba,  one  of  the  beaches  of  Lake 
Agassiz  has  been  named  by  the  settlers  Orange  Ridge,  from  its  orange-red 
lilies,  and  another  is  called  the  Rose  Ridge. 

DEVEIiOPMBNT  OF  AGRICULTURE. 

The  aboriginal  tribes  of  Ojibways  and  Dakotas,  living  on  the  southern 
portion  of  the  area  of  Lake  Agassiz,  had  made  little  progress  toward  a  sys- 
tem of  agriculture  which  would  provide  their  principal  food  during  the 
whole  year.  Like  the  other  tribes  of  hunting  Indians  who  inhabited  all 
the  area  of  the  United  States,  excepting  its  southwestern  borders,  their 
dependence  was  chiefly  on  the  chase  and  entrapping  of  game  and  on  fishing. 
But  even  their  rude  and  very  limited  efforts  in  agriculture  yielded  an  impor- 
tant and  valued  portion  of  their  sustenance.  In  pre-Columbian  times  and 
onward  to  the  present  day  the  Indians  have  cultivated  small  patches  of 
land,  carefully  tending  their  crops  and  storing  up  the  harvest  for  gradual 
use  during  the  rigors  of  winter  and  until  the  next  harvest,  supj)lementing 


INDIAN  AGEICULTUEE.  611 

thereby  their  principal  diet  of  game  and  fish.  Such  aboriginal  agriculture, 
untaught  by  wliite  men,  yet  far  from  being  despicable,  I  saw  in  September, 
1885,  at  the  Ojibway  village  a  mile  southeast  of  the  Narrows  of  Red  Lake. 
This  largest  village  of  the  Ojibway s  in  Minnesota  consists  of  thirty  or  forty 
permanent  bark  lodges,  scattered  on  an  area  which  reaches  a  half  mile  from 
northwest  to  southeast,  and  is  40  to  60  rods  wide.  Adjoining  the  village 
were  fields  of  ripening  maize  or  Indian  corn,  amounting  to  about  50  acres, 
besides  about  5  acres  of  potatoes  and  probably  an  acre  or  more  of  squashes. 
These  crops  showed  a  luxuriant  growth  and  abmidant  yield,  and  the  weeds 
among  them  had  been  held  in  check  by  hoeing.  During  the  spring,  sum- 
mer, and  autumn,  most  of  the  one  hundred  and  fifty  or  two  hundred  inhab- 
itants of  this  village  are  usually  absent  in  expeditions  for  hunting,  and  in 
successive  portions  of  the  season  to  make  maple  sugar,  to  gather  Seneca 
snakeroot  for  sate,  to  pick  cranberries,  and  to  reap  the  natural  harvest  of 
wild  rice  (Zisania  aquatica  L.)  which  grows  plentifully  in  the  streams  and 
shallow  lakes  and  forms  the  most  substantial  part  of  the  provisions  laid 
up  for  the  winter.^  In  the  prairie  country  the  place  of  the  wild  rice  is  par- 
tially supplied  by  the  very  nutritive,  turnip-like  root  of  the  pomme  de  terre 
(Psoralea  escidenta  Pursh),  which  is  dried,  pulverized,  and  used  as  flour  by 
the  Dakotas.^ 

At  an  earlier  time,  of  which  no  distinct  tradition  is  preserved  by  the 
hunting  tribes  of  Indians  inhabiting  this  region,  other  tribes,  who  built 
the  mounds  and  probably  lived  more  by  agriculture  and  less  by  the  chase, 
overspread  all  the  prairie  district  of  Lake  Agassiz,  extending  also  east  in 
the  wooded  country  to  Rainy  Lake.  The  enduring  earthworks  erected  by 
this  people  testify  of  their  formerly  wide  extension  throughout  the  Missis- 
sippi and  Red  River  basins,  and  show  that  the  sites  of  their  villages  were 
chosen  usually  on  the  banks  and  bluffs  which  overlook  the  food-giving 
rivers  and  lakes,  often  commanding  an  extensive  and  beautiful  prospect. 
Most  of  the  mounds  within  the  area  of  Lake  Agassiz  are  round  and  have 
the  form  of  a  dome,  their  height  ranging  from  3  to  10  feet  or  rarely  more 

I  The  Flora  of  Minnesota,  in  the  Twelfth  Annual  Report,  Geol.  ami  Nat.  Hist.  Survey  of  Minne- 
sota, for  1883,  p.  159. 
2Ibid.,  p.  42. 


612  THE  GLACIAL  LAKE  AGASSIZ. 

above  the  general  surface,  with  a  diameter  of  30  to  100  feet  or  more  at 
their  base.  Nearly  all  of  them  were  made  by  the  people  for  the  burial 
of  their  dead,  and  the  relics  found  with  their  bones  prove  that  they  sur- 
passed the  present  Indians  of  this  region  in  having  skill  to  make  rude 
pottery,  but  the  superiority  was  very  slight,  and  there  ai-e  no  evidences 
of  the  development  of  handicrafts  to  a  degree  at  all  comparable  with  the 
aboriginal  arts  of  Mexico  and  Peru.  There  was  some  commercial  inter- 
change from  great  distances,  but  it  was  probably  limited  to  a  few  articles 
which  were  highly  valued  for  beauty  or  regarded  as  mysterious  and  sacred. 
Thus  in  the  mounds  on  the  bluffs  of  the  Som-is  River  and  Antler  creeks,  in 
southwestern  Manitoba,  Prof  George  Bryce  found  ornaments  made  of  sea 
shells,  others  of  copper  from  Lake  Superior,  and  pipes  from  the  sacred  red 
pipestone  quarry  at  Pipestone,  Minn.,  which  Longfellow  has  described  in 
"The  Song  of  Hiawatha." 

Further  notes  of  the  mounds  of  the  area  of  Lake  Agassiz  and  the 
adjoining  country  on  the  west  are  given  in  Appendix  B. 

The  first  immigration  of  white  men  to  colonize  the  fertile  basin  of  the 
Red  River  of  the  North,  bringing  the  civilized  arts  and  agriculture  of 
Europe,  was  in  the  years  1812  to  1816,  when,  under  Lord  Selkirk's  far- 
sighted  and  patriotic  supervision,  the  early  pioneers  of  the  Selkirk  settle- 
ments, coming  by  the  way  of  Hudson  Bay  and  York  Factory,  reached 
Manitoba  and  established  their  homes  along  the  river  from  the  vicinity  of 
Winnipeg  to  Pembina.  In  its  beginning  this  colony  experienced  many 
hardships,  but,  in  the  words  of  one  of  these  immigrants,  whose  nan-ative 
was  written  down  in  his  old  age,  in  1881,  "by  and  by  our  troubles  ended, 
war  and  famine  and  flood  and  poverty  all  passed  away,  and  now  we  think 
there  is  no  such  place  to  be  found  as  the  valley  of  the  Red  River."  ^ 

Fifty  to  sixty  years  after  the  founding  of  the  Selkirk  colony  the  mar- 
gin of  the  advancing  w^ave  of  immigration  in  the  United  States  reached 
the  Red  River  Valley.  In  a  few  places  on  the  Red,  Wild  Rice  (of  North 
Dakota),  and  Sheyenne  rivers  small  bands  of  immigrant  farmers  had  begun 
the  settlement  of  this  rich  agricultural  area  a  few  years  before  the  building 

'  Manitoba :  Its  Infancy,  Growth,  and  Present  Condition,  by  Prof.  George  Bryce,  London,  1882, 
p.  166. 


IMMIGEATION  AND  AGEIOULTURAL  DEVELOPMENT.  613 

of  railroads  across  it;  but  the  main  tide  of  immigration  came  after  the  rail- 
roads had  provided  means  of  sending  the  staple  product  of  the  country, 
■wheat,  to  the  markets  of  St.  Paul,  Minneapolis,  and  Duluth.  The  Northern 
Pacific  Railroad  was  built  from  Duluth  to  Moorhead  and  Fargo  during  the 
years  1870  to  1872,  and  the  next  year  it  was  extended  to  Bismarck.  Within 
the  next  three  years  a  line  of  the  Great  Northern  Railway  (then  the  St. 
Paul  and  Pacific)  was  built  to  Breckenridge,  and  another  line  to  Crookston 
and  St.  Vincent.  From  1875  to  1885  the  settlement  of  the  Red  River 
Valley  and  of  a  large  contiguous  area  of  North  and  South  Dakota  went 
forward  very  rapidly,  nearly  all  the  land  in  this  valley  being  taken  up 
during  these  ten  years  by  homestead  and  preemption  claims  from  the 
Government  and  by  purchase  from  the  railroad  corporations  which  had 
received  land  grants. 

The  wise  policy  of  the  United  States  Government  was  to  parcel  out  its 
land  in  small  farms  to  actual  settlers,  selling  none  to  non-residents,  and 
allowing  to  no  one  rights  to  secure  more  than  three-quarters  of  a  section, 
or  a  total  of  480  acres.  This  large  amount  was  possible  to  be  obtained 
from  the  Government  only  by  use  of  three  separate  rights,  each  securing 
a  quarter  section,  according  to  the  respective  laws  for  homesteads,  preemp- 
tion, and  tree  culture.  Most  of  the  farms  received  from  the  Government 
comprise  only  160  acres;  and  these  were  deeded,  upon  payment  of  small 
fees  at  the  land  offices,  to  any  citizen,  including  naturalized  foreigners,  those 
aflfirming  their  intention  to  become  naturalized  legal  voters,  and  widows  and 
unmarried  women,  all  of  whom  were  required  to  take  the  land  to  be  their 
permanent  homes.  For  these  free  gifts  of  the  fertile  prairie  of  the  Red 
River  Valley,  surpassed  by  no  other  area  of  the  world  in  its  natural  value 
for  agriculture,  multitudes  came,  bringing  housekeeping  equipments  in  their 
emigi-ant  wagons  ("prairie  schooners"),  which  passed  in  long  processions 
tlu-ough  St.  Cloud  and  Alexandria,  Minn.,  on  their  way  from  the  older  por- 
tions of  that  State  and  from  other  States  farther  east  and  south.  Many 
also  came  directly  from  the  Old  World,  especially  from  Sweden  and 
Norway,  being  carried  from  the  eastern  seaports  by  railroads  to  the  Red 
River  and  James  River  valleys  and  other  parts  of  North  and  South  Dakota, 


614  THE  GLACIAL  LAKE  AGASSIZ. 

there  being  welcomed  and  soon  established  on  their  own  freeholds  in  near 
neighboi'hood  with  others  of  their  countrymen  who  had  come  to  the  United 
States  many  years  earlier. 

A  considerable  number  of  very  large  farms  were  acquired,  however, 
by  discerning  capitalists,  who  saw  the  capabilities  of  this  district  for  the 
convenient  employment  of  large  companies  of  laborers,  marshaled  with 
almost  military  order,  in  the  various  operations  of  farming,  as  in  plowing, 
seeding,  harvesting,  and  thrashing,  and  who,  at  an  early  stage  in  the  rapid 
progress  of  settlement,  foresaw  the  profits  of  wheat  raising  on  a  grand  scale. 
These  "bonanza  farms,"  as  they  were  afterward  called,  were  made  up  in 
great  part  by  purchasing  from  the  railroad  corporations  the  odd-numbered 
alternate  sections  which  had  been  given  as  Government  subsidies  to  foster 
the  early  railroad  enterprises  that  opened  the  region  to  settlement.  But  the 
railroad  lands  formed  no  compact  tract,  being  in  square  miles  touching  each 
other  only  at  the  corners,  like  the  spots  of  a  single  color  on  a  checkerboard. 
To  remedy  the  difficulty  and  fill  out  continuous  tracts,  many  of  the  inter- 
vening portions  Avere  obtained  by  purchase  from  settlers  who  had  received 
the  laud  from  the  Grovernment  in  good  faith,  with  the  full  intention  of 
continuing  to  live  on  it;  but  in  some  instances  claims  also  were  obtained 
from  the  Government  by  fraudulent  agents,  who  professed  their  intention  to 
comply  with  this  legal  requirement  in  taking  land  by  preemption. 

Among  the  most  famous  and  successful  of  these  extensive  fanns  are 
the  Lockhart  and  Keystone  farms,  in  Minnesota;  that  of  the  Messrs.  Dal- 
rymple,  comprising  some  30,000  acres,  in  the  vicinity  of  the  station  of  this 
name  on  the  Northern  Pacific  Raih'oad,  18  miles  west  of  Fargo;  the  lands 
of  the  Grandiu  Farming  Company,  about  40,000  acres,  in  eastern  Traill 
County;  and  the  Elk  Valley  Farm,  near  Larimore.  Nine  establishments 
of  farm  buildings  have  been  erected  by  the  Grandin  Farming  Company,  and 
these  are  connected  with  the  headquarters  (Hague  post-office)  by  25  miles  of 
telephone  lines,  the  farthest  set  of  buildings  being  at  a  distance  of  12  miles. 
About  280  horses  and  mules  are  used  by  this  company,  and  200  to  300  men 
are  employed  during  the  summer,  distributed  somewhat  equally  in  the  nine 
divisions;  but  in  winter,  when  comparatively  few  men  are  retained,  the 


WHEAT  EAISING.  615 

horses  are  stabled  at  only  two  or  three  places.  One  stable  at  the  head- 
quarters has  180  stalls.  In  some  fields  of  this  great  farm  the  teams  plow  3 
or  4  miles  straight  forward,  being  interrupted  only  by  roads  on  the  section 
lines,  where  the  plow  is  thrown  out  of  the  ground  for  a  few  rods.  The 
first  breaking  on  both  the  Dalrymple  and  Grandin  farms  was  in  1875,  the 
same  year  in  which  the  land  was  mostly  purchased,  and  their  first  crop  of 
wheat  was  harvested  in  1876.  During  every  year  since  that  time  the  har- 
vests on  these  lands  and  in  general  tln-oughout  the  Red  River  Valley  have 
been  good,  with  no  failure  on  account  of  di'ought,  which  for  several  years 
(from  1885  to  1889)  was  very  severe  upon  many  portions  of  the  Dakotas 
west  and  southwest  of  this  valley. 

WHEAT  AND  OTHER  CEREALS. 

One  man,  if  very  industrious,  with  two  pairs  of  horses  and  ample  "farm 
machinery" — that  is,  plows,  harrows  (here  often  called  drags),  seeders,  a 
self-binding  harvester,  etc. — can  cultivate  100  to  150  acres  in  wheat.  An 
intelligent  and  energetic  farmer  in  Traverse  County,  Minn.,  with  whom  I 
conversed  in  June,  1886,  informed  me  that  during  the  preceding  autumn, 
beginning  after  the  harvest  and  working  daily  until  the  ground  froze,  he 
plowed  130  acres,  walking  behind  the  plow.  In  the  spring  of  1886  the 
seeding  of  his  crop  of  210  acres  was  done  entirely  by  his  wife,  not  an 
especially  strong  woman,  who  rode  on  the  seeder,  driving  a  pair  of  horses, 
while  he  with  another  pair  was  di'agging  (harrowing)  the  plowed  lands  to 
prepare  them  for  seeding.  He  expected  to  harvest  the  whole  with  one  har- 
vester, estimating  that  this  would  occupy  fifteen  days,  working  from  the 
time  when  the  dew  would  be  mostly  gone  in  the  morning  until  it  would 
gather  heavily  in  the  evening-.  The  amount  of  work  accomplished,  how- 
ever, by  most  farmers  with  their  hired  men  is  no  more  than  to  cultivate  50 
or  75  acres  in  wheat  for  each  man  laboring  tlu'ough  the  season. 

The  seedtime  for  wheat,  oats,  and  barley  is  shortly  after  the  ground 
is  thawed  in  the  spring,  usually  occupying  the  second  half  of  April  and  the 
first  week  or  two  of  May.  The  harvest  comes  during  August,  northward 
extending  somewhat  into  September,  after  which  follow  stacking,  thrashing, 
and  plowing,  until  winter  arrives.     Harvesting  is  the  busiest  part  of  the 


616  THE  GLACIAL  LAKE  AGASSIZ. 

farmer's  work,  since  the  crop  ought  to  be  secured  as  soon  as  it  is  ripe. 
Delay  permits  much  of  the  wheat  to  be  shelled  out  of  the  heads  and 
scattered  on  the  ground.  There  is  also  much  liability  to  loss  at  this  time 
from  the  occuiTence  of  rainy  weather,  and  hail  may  destroy  or  greatly 
damage  the  crop  at  any  time  after  it  has  attained  a  considerable  height 
until  it  is  cut. 

Usually,  if  the  season  is  favorable,  the  first  crop  from  newly  broken 
prairie  land  is  somewhat  more  bountiful  than  any  to  be  obtained  in  the 
following  years,  which  range  from  10  to  20  bushels  of  wheat  on  an 
average  per  acre.  The  same  fields  have  in  many  instances  been  successfully 
cultivated  in  Avheat  ten  to  fifteen  years  or  more  in  the  Red  River  Valley 
south  of  the  international  boundary,  and  twice  as  long  in  other  parts  of 
Minnesota  and  in  the  Selkirk  settlements  of  Manitoba,  Avithout  the  use 
of  any  manm-e,  and  yet  without  exhibiting  any  noticeable  impoverishment 
of  the  soil.  The  time  must  come,  however,  after  a  few  decades  of  such 
unrequited  cropping,  when  fertilizers  will  be  needed  to  restore  and  sustain 
the  original  productiveness. 

A  rotation  of  crops  and  diversity  of  farming,  with  stock  raising  and 
butter  making,  will  doubtless  be  found  more  advantageous  than  the  pro- 
duction of  the  cereals  only,  when  a  long  series  of  years  is  considered.  The 
growth  of  villages  and  towns  in  this  district,  affording  near  markets  for 
miscellaneous  farm  produce,  and  the  tendency,  with  the  increase  of  popu- 
lation, toward  subdivision  of  the  large  farms,  and  even  of  the  ordinary 
homesteads,  into  two  or  four  farms  in  each  quarter  section,  indicate  for  the 
future  an  increasing  diversification  of  agriculture.  Wheat  and  other  cereals 
will  probably  continue  to  be  the  chief  crops  for  exportation,  but  many  other 
crops  will  attain  more  importance  than  now,  and  there  will  be  a  greatei' 
average  expenditure  of  labor  for  each  acre  cultivated,  with  proportionally 
enhanced  profits. 

Comparatively  few  Indians  were  able  to  derive  their  subsistence  by 
hunting  and  fishing  upon  the  area  of  Lake  Agassiz  or  in  any  other  region. 
Probably  their  numbers  living  at  any  time  upon  the  portion  of  this  lake 
area  within  the  United  States  did  not  exceed  5,000.  But  now  that  the  land 
is  occupied  by  white  immigrants  and  is  sown  with  wheat,  the  present  yearly 
product  is  about  285  bushels  apiece  for  each  man,  woman,  and  child  of  the 


STATISTICS  OF  WHEAT  PEJDUCTION. 


617 


161,049  enumerated  by  the  census  of  1890  in  the  twelve  counties  which  lie 
mainly  within  the  Red  River  Valley. 

Six  of  these  counties  are  in  Minnesota  and  six  are  in  North  Dakota. 
Tabulations  of  their  population  in  1880  and  in  1890,  and  of  their  pro- 
duction of  wheat  during  the  same  years  in  Minnesota  and  during  1879  and 
1891  in  North  Dakota,  are  here  presented,  for  the  pur230se  of  exhibiting  the 
rapid  progress  in  the  agricultural  development  of  the  district.  The  ratio  of 
the  wheat  yield  to  the  population  in  1880  was  69  bushels  for  each  person, 
or  less  than  one-fourth  as  much  as  in  1890  and  1891.  The  latter  high  ratio 
of  285  bushels  for  each  person  is  probably  near  the  maximum  which  this 
ratio  can  attain,  from  which  it  will  decrease  relatively  to  the  increasing 
population,  the  place  of  wheat  cultivation  being  destined  to  he  partially 
taken  by  other  crops,  by  stock  raising,  and  by  other  industries. 

An  equally  prosperous  development  of  the  agricultural  resources  of 
Manitoba  has  been  going  forward  during  the  same  time,  as  is  also  exhibited 
by  the  similar  statements  of  the  population  and  wheat  production  of  that 
province. 

Population  of  counties  m  Minnesota  lying  mainly  within 
the  lied  Iliver  Valleij. 


Counties. 

18R0. 

1890. 

Wilkin          

1,900 

5,887 

4,346 
11,517 
10,018 
30, 192 
9,130 
5,387 

Clay 

Polk     ..                     

11,433 
092 
905 

Marshall 

Total            '                          

21, 123 

71, 190 

'  Organized  in  1881  from  part  of  Polk  County. 

Population  of  counties  in  North  DaVota  lying  mainly 
u-ithin  the  lied  Hirer  Valley. 


Counties. 

1880. 

1890. 

3,597 
8,998 
4,123 
6.248 

10,751 
19,013 
10,217 
18,357 
16,  587 
14,  334 

Traill 

Walsh' 

4,802 

Total                                          

27,828 

89,  859 

'Organized  in  1881  JVoni  parts  of  Granil  Forks  and  Pembina  counties. 


618 


THE  GLACIAL  LAKE  AGASSIZ. 


The  population  of  Manitoba,  according  to  the  census  of  1881,  was 
69,954;  and  in  1891  it  was  estimated  to  be  150,000.  About  a  third  part 
of  these  and  a  small  ft-action  of  the  population  noted  in  the  Minnesota  and 
North  Dakota  counties  are  outside  the  boundaries  of  Lake  Agassiz;  but 
the  total  inhabitants  within  the  lake  area  are  nearly  a  quarter  of  a  million 
people.  Approximately  three-fourths  of  this  population  are  engaged  in 
farming,  the  other  fourth  being  resident  in  the  villages  and  large  towns 
and  engaged  in  commercial  and  manufacturing  pursuits. 

Wheat  production  of  counties  in  Minnesota  h/ing  mainly  tvithin  the  Bed  Biver  VaUey. 


Counties. 

1880. 

1890. 

Acres. 

Bushels. 

Bushels 

per  acre. 

Acres. 

Bushels. 

Bushels 
per  acre. 

Wilkin                               

9,871 
28,444 

144,424 
479,  833 

14.60 
16.87 

42,212 
93,  568 
84, 188 
222,  223 
88,  819 

474,  050 
1,  284,  651 
1,  293,  429 
3, 002.  754 
1,056,425 

11.20 
13.70 
15.30 
13.50 
11.80 

Clav                                       

Polk 

63,135 
1,121 

1,035,428 
17,  367 

16,40 
15.49 

Total 

103,  363 

1,  692, 183 

16.37 

(531,010) 
=600,  000 

(7,  111,  209) 
'8,000,000 

13.33 

^  Not  reported.  'Including  estimated  addition  for  Kittson  County. 

Wheat  production  of  counties  in  North  Dakota  lying  mainly  within  the  Bed  Biver  Valley. 


Counties. 

1879. 

1891.                             1 

Acres. 

Bushels. 

Bushels 
per  acre. 

Acres. 

Bushels. 

Bushels 
per  acre. 

9, 086 
51,727 
13,  707 

4,978 

184,  753 

1,  012,  565 

333,  409 

98,  352 

20.33 
19.57 
24.32 
19.76 

156,  631 
527,  070 
269,  426 
262,  992 
241,  673 
218,066 

3, 195, 680 
9,  939,  034 
6, 441.  546 
6,  881, 624 
6,  202, 940 
5,  202,  332 

20.40 
18.86 
23.88 
26.17 
25.67 
23.86 

Traill 

Walsh 

2,398 

63,  676 

26.55 

Total 

81,  896 

1,692,755 

20.67 

1,  675,  858 

37,  863, 156 

22.59 

Wheat  production  of  Manitoia. 


1883.                           1                            1891. 

Acres. 

Bushels. 

Bushels 
per  acre. 

Acres. 

Bushels. 

Bushels 
neracre. 

Whole  province 

208,674 

4,549,093 

21.80 

916, 664 

23, 191, 599 

25.30 

Summing  these  figures,  and  deducting  the  estimated  portion  belonging 
outside  the  boundaries  of  the  glacial  lake,  we  find  the  present  annual  wheat 
crop  upon  the  praii-ie  area  of  Lake  Agassiz  to  be  approximately  50,000,000 
bushels.     This  is  about  200  bushels  apiece  for  each  inhabitant,  when  the 


STATISTICS  OF  WHEAT  AND  OATS. 


619 


populations  in  the  United  States  and  in  Manitoba  are  considered  together; 
and  if  the  wheat  were  distributed  among  all  the  people  of  the  United  States, 
it  would  supply  nearly  a  bushel  for  each  individual.  But  no  more  than  a 
quarter  part  of  the  arable  prairie  land  of  this  lacustrine  area  is  now  under 
cultivation  in  all  crops,  the  proportion  being  greater  in  the  United  States 
and  less  in  Manitoba.  When  all  this  area  shall  be  brought  into  agriculture, 
the  wheat  product  will  probably  be  almost  or  quite  200,000,000  bushels 
yearly,  but  the  ratio  to  the  population  of  the  Red  River  Valley  will  be 
smaller  than  now. 

All  the  wheat  raised  in  this  district  is  sown  in  the  spring,  none  being 
"winter  wheat,"  sown  in  the  fall.  The  kernel  is  plump  and  hard,  yielding 
in  the  "roller  mills,"  with  the  present  perfected  processes  of  manufacture, 
the  finest,  whitest,  and  most  salable  ilour  of  the  world.  Nearly  every  city 
and  large  village  in  Minnesota,  North  Dakota,  and  Manitoba,  has  one  or 
more  flouring  mills;  but  far  the  greater  part  of  the  wheat  crop  is  shipped 
eastward,  by  W9.y  of  Duluth,  Superior,  and  Port  Arthur,  to  milling  cities  on 
the  Great  Lakes,  excepting  the  large  fraction  which  is  marketed  in  Minne- 
apolis, whose  flouring  mills  have  a  daily  capacity  of  about  30,000  barrels. 

Production  of  oats  in  the  year  1S90  in  counties  of  Minnesota  lying  mainlij 
within  the  Bed  River  Valley. 


Counties. 

Acres. 

Bushels. 

Bushels 
per  acre. 

Wilkin    

10,  004 
23,  609 
18,  094 
38, 839 

11,  438 

238,  285 
659,  738 
585,  785 
1,044,406 
256,  569 

23.80 
27.90 
31.30 
26.80 
22.40 

Clay 

Polk 

Marshall 

Kittson ' 

Total 

102,  584 

2,  784, 773 

27.15 

iNot  reported. 

Production  of  oats  in  the  year  1S91  in  counties  of  North  Dakota  lying 
mainly  within  the  Bed  Biver  Valley. 


Counties. 

Acres. 

Bushels. 

Bushels 
per  acre. 

24,  355 
70,  095 

33,  689 
38,  334 
33, 341 

34,  546 

901, 135 
2,777,303 
1,  494,  949 
1,  854,  S40 
1,476,215 
1,  579,  246 

37 

39.29 

44.37 

48.40 

44.28 

45.71 

Cass 

Traill                                                                     

Walsh '                                                               

Total 

234,  960 

10,  083,  788 

42.90 

620 


THE  GLACIAL  LAKE  AGASSIZ. 

Production  of  oats  in  the  year  1S91  in  Manitoba. 


Acres. 

Bushels. 

Bushels 
per  acre. 

305,644 

14,  762,  605 

48.30 

Production  of  barley  in  the  i/ear  1S90  in  counties  of  Minnesota  lying 
mainly  within  the  Bed  River  Valley. 


Counties. 


Wilkin  .. 

Clay 

Korraan.. 

Polk 

Marshall . 
Kittson  * . 


Total  . 


1,961 
3,842 
2,925 
14, 120 
13,  043 


35,  891 


Bushels. 


45,  784 
104,  955 

80, 145 
298,  017 
145,  950 


Bushels 
per  acre. 


23.30 
27.30 
27.40 
21.10 
11.10 


^  Not  reported. 

Production  of  barley  in  the  year  1S91  in  counties  of  North  Dakota  lying 
mainly  within  the  Bed  Biver  Valley. 


Counties. 

Acres. 

Bushels. 

Bushels 
per  acre. 

4,900 
12, 915 
11,091 
18,  359 
14,  397 
22,  950 

158,136 
416,  508 
402, 157 
682,  343 
559,  883 
826,  200 

32.27 
32.25 
36.25 
37.17 
38.89 
36 

Traill 

Walsh                 

Total 

84,  615 

3,045,227 

35.99 

Production  of  barley  in  the  year  1891  in  Manitoba. 


"Whole  province . 


Acres. 


89,  828 


Bushels. 


3, 197, 876 


Bushels 
per  acre. 


Rye  is  only  sparingly  cultivated  in  this  district.  The  total  area  of 
this  grain  in  the  six  Minnesota  counties  in  1890  was  423  acres,  yielding 
6,541  bushels,  an  average  of  15.46  bushels  per  acre.  In  the  six  counties 
of  North  Dakota  774  acres  of  rye  were  reported  in  1891,  with  a  yield  of 
about  19,139  bushels,  or  an  average  of  nearly  25  bushels  per  acre. 

The  season  between  the  last  severe  frost  of  spring  and  the  earliest  in 
autumn  is  often  too  short  for  the  maturing  of  maize,  or  Indian  corn,  which, 
therefore,  will  never  be  raised  extensively  in  the  Red  River  Valley.     In 


INDIAN  COKN,  HAY,  AND  OTHEE  CEOPS. 


621 


the  same  counties  of  Mimiesota  2,026  acres  were  planted  with  maize  in 
1890,  the  yield  being  44,125  bushels,  averaging  21.78  bushels  per  acre; 
and  in  the  North  Dakota  counties  there  were  5,685  acres  of  maize  in  1891, 
yielding  148,217  bushels,  or  26.07  bushels  per  acre. 

HAY,    POTATOES,    FLAX,    AND    OTHER    CROPS. 

The  principal  grasses  cultivated  for  hay  in  the  prairie  region  of  Lake 
Agassiz  are  the  Italian  millet,  or  Hungarian  grass  (^Setaria  italica  Kunth), 
and  timothy  (^Phleum  pratense  L.).  In  Minnesota  these  are  not  kept  sepa- 
rate by  the  report  of  the  commissioner  of  statistics,  but  in  North  Dakota 
the  returns  to  the  State  department  of  agriculture  show  that  the  millet 
crop  far  exceeds  that  of  all  other  cultivated  grasses  (here  known  as  "tame 
grasses").  The  Minnesota  repoi'ts  state  the  quantity  of  wild  hay  made  on 
the  unbroken  prairie,  which  in  the  Red  River  Valley  often  yields  a  ton  of 
very  good  hay  per  acre  on  the  somewhat  dry  general  surface  and  2  to 
3  tons  of  an  inferior  quality  on  marshy  ground.  The  wild  hay  gathered 
in  the  North  Dakota  counties  is  not  reported,  but  doubtless  surpasses 
the  figures  of  Minnesota,  which  has  only  about  one-third,  while  North 
Dakota  has  about  two-thirds  of  the  width  of  the  Red  River  Valley.  With 
the  prospective  increase  of  attention  to  stock  raising  and  dairying,  the 
cultivation  of  hay  will  become  more  prominent.  Timothy,  redtop,  and 
other  choice  perennial  species  will  probably  then  come  more  into  favor, 
displacing  in  part  the  present  coarse  fodder  supplied  by  the  annually  sown 
fields  of  millet. 

Production  of  hay  in  the  year  1S90  in  counties  of  Minnesota  lying  mainly 
within  the  lied  River  Valley. 


Counties. 

Cultivated  hay. 

Wild  hay. 

Acrea. 

Tons. 

Per  acre. 

Tons. 

990 
2,840 
5,113 
0,  082 
1,883 

1,616 

4,642 
11,  286 
6,840 
2,798 

1.63 
1.64 
2.21 
1.35 
1.49 

11,  757 
40, 114 
32,  395 
72,  733 
26, 104 

Clay   

Polk                          .... 

Kittaon'                

Total 

15,  908 

27, 182 

1.71 

183, 103 

'Not  reported. 


622 


THE  GLACIAL  LAKE  AGASSIZ, 


Production  of  hay  in  the  ijcar  ISOl  in  counties  of  Xorth  JJaliota  lying 
mainly  within  the  Red  llivcr  Valley. 


Counties. 

Millet  (Hungarian  grass). 

Other  cultivated  hay. 

Acres. 

Tons. 

Per  acre. 

Acres. 

Tons. 

Per  acre. 

RicbLind 

3,942 
12,  870 

8,235 
15,  901 
10,827 

8,313 

8,  672 
31,102 
19,  215 
37,  632 
24,  360 
19,  397 

2.20 
2.42 
2.67 
2.37 
2.25 
2.33 

936 
3,965 
3,959 
3,147 

2,782 
690 

1,248 
7,731 
5,938 
5,114 
4,868 
1  nil 

1.33 
1.95 
1.50 
1.62 
1.75 
1.60 

Cass 

Traill 

Grand  Forks 

Walsh    

Total 

60,  088 

140,  378 

2.34 

15,  479         25,  943 

1.68 

The  crops  of  oats,  hay,  and  potatoes  raised  in  the  Red  River  Valley 
are  almost  all  consumed  by  the  farmers  themselves,  excepting  the  part  sold 
for  use  in  the  villages  and  cities  of  the  district.  It  seems  probable,  how- 
ever, that  the  cultivation  of  potatoes  for  exportation  to  Minneapolis  and  St. 
Paul,  to  Duluth  and  West  Superior,  and  to  the  mining  towns  of  Montana, 
would  be  on  the  average  as  remunerative  as  wheat  raising. 

Production  of  potatoes  in  the  year  1S90  in  counties  of  Minnesota  lying 
mainly  within  the  Eed  River  Valley. 


Counties. 

Acres. 

Bushels. 

Per  acre. 

Wilkin 

202 
1,174 

579 
3,081 

476 

17, 527 
119,  934 

84,  401 
174,  657 

30,  894 

86.77 
102. 16 
145.  77 
56.69 
64.90 

Clay 

Polk 

Marshall 

Kittson' 

Total 

5,512 

427,  413 

77.54 

*  Not  reported. 

Production  of  imtatoes  in  the  year  1S91  in  counties  of  North  Dakota  lying 
mainly  withiti  the  Red  River  I'alley. 


Counties. 

Acres. 

Bushels. 

Per  acre. 

Kichland 

1,972 
1,645 
654 
1,157 
1,545 
1,146 

247,  305 
251,  685 
103,  550 
243,  697 
346,  767 
319,  243 

126 
153 
158 
211 
224 
279 

Cass 

TraiU 

Walsh 

Pembina 

Total 

8,119 

1,  512,  247 

186 

In  Manitoba  12,705  acres  were  planted  with  potatoes  in  1891,  yielding 
2,291,982  bushels,  or  an  average  of  180.4  bushels  per  acre. 


POTATOES,  FLAXSEED,  AND  OTHER  CROPS. 


623 


Flax  is  considerably  cultivated  iii  the  Red  River  Valley,  chiefly  south 
of  the  international  boundary,  the  seed  being  sold  for  the  extraction  of 
linseed  oil.  None  of  the  flax  of  this  country  is  used  for  the  manufacture 
of  linen,  although  it  seems  wholly  suitable  for  that  industry. 

Prodxiotion  of  flaxseed  in  the  year  1890  in  counties  of  Minnesota  lying 
mainly  within  the  Bed  River  Valley. 


Counties. 

Acres. 

Easbels. 

Per  acre. 

Wilkin 

1,005 
516 
475 
289 
210 

7,761 
4,987 
3,  594 
2,749 
1,161 

7.70 
9.60 
7.50 
9.50 
5.50 

Clav 

Pollt  

Marshall 

Kittson' 

Total 

2,494 

20,  252 

8.12 

1  Not  reported. 

Production  of  flaxseed  in  the  year  ISOl  in  coimties  of  North  Dakota  lying 
mainly  within  the  Red  River  Valley. 


Counties. 

Acres. 

Bushels. 

Per  acre. 

2,079 
1,745 
1,703 
1,559 
4,927 
38 

24,  717 
19,195 
20,436 
22,  818 
77,  994 
494 

11.89 

11 

12 

14.64 

15.83 

13 

Traill        

Grand  Forks     . .     . .        .... 

Walsh '. 

Total 

12,051 

165,654 

13.76 

The  light,  sandy  soil  best  adapted  for  buckwheat  is  found  within  the 
prairie  area  of  Lake  Agassiz  only  on  its  deltas,  and  this  crop  has  been  very 
scantily  raised. 

Sorghum,  which  is  much  cultivated  for  the  manufacture  of  sirup  in 
southern  Minnesota,  requires  a  longer  season  than  is  free  from  frosts  in  the 
Red  River  Valley. 

Most  of  the  common  garden  produce,  as  peas,  beans,  tomatoes,  beets, 
carrots,  turnips,  cabbages,  squashes,  melons,  etc.,  can  be  successfully  grown 
in  this  district;  but  in  the  heavy  labor  given  to  the  staple  crops,  as  wheat 
and  oats,  these  valuable  additions  to  the  farmer's  household  fare  have  been 
too  generally  forgotten  or  neglected.  There  is,  however,  an  evident  increase 
of  attention  to  these  crops,  both  for  home  use  and  for  sale  in  the  cities. 


624 


THE  GLACIAL  LAKE  AGASSIZ. 


The  winter  climate  is  too  severe  tor  apples,  pears,  peaches,  plums,  and 
grapes;  but  many  hardy  small  fruits,  as  currants,  gooseberries,  raspberries, 
blackberries,  and  strawberries,  thrive  and  yield  bountifully  wherever  they 
receive  proper  care. 

STOCK    RAISING    AND    DAIRYING. 

During  the  early  years  of  rapid  development  of  wheat  raising,  little 
labor  or  thought  was  given  to  stock  and  the  dairy.  Most  of  the  farmers 
bought  for  their  work  imported  horses  which  had  been  raised  in  Iowa  or 
adjoining  States.  Butter  also  was  imported  from  the  same  States,  and 
the  majority  were  willing  to  live  without  fresh  meat  or  milk.  Nowhere, 
however,  can  more  favorable  climate  and  natural  conditions  be  found  for 
the  successful  raising  of  all  the  stock  needed  by  the  farmer  in  diversified 
agriculture  and  for  the  dairy  than  in  the  Red  River  Valley.  Recently, 
therefore,  many  entei"])rising  farmers  have  secured  the  best  blooded  stock 
of  horses,  cattle,  sheep,  and  hogs;  and  this  portion  of  the  farming  inter- 
ests of  the  district  bids  fair  to  assume  its  due  importance.  In  the  near 
future  probably  the  sale  of  butter  and  cheese  will  form  one  of  the  prin- 
cipal sources  of  income  in  many  townships.  Poultry  and  eggs  are  also 
coming  to  be  considered  a  needful  part  of  every  provident  farmer's 
resources. 

The  following  tables  give  the  numbers  of  live  stock  in  the  counties  of 
the  Red  River  Valley  in  Minnesota  and  North  Dakota.  By  the  kindness 
of  H.  T.  Helgesen,  commissioner  of  agriculture  and  labor  for  North  Dakota, 
the  assessed  valuations  of  the  horses  and  cattle  in  the  counties  of  that  State 
are  also  noted. 

Live  stock  in  1S91  in  counties  of  Minnesota  lying  mainly  within  the  Bed  Siver  Valley. 


Counties. 

Horses, 

mules,  and 

asses. 

Cattle. 

Sheep. 

Swine. 

Wilkin     

Number. 
3,373 
6,405 
6,682 
13, 108 
4,425 
3,917 

Number. 

5,485 
13,  201 
13,  595 
30,  214 
10,433 

7,666 

Number. 
1,387 
6,601 
4,656 
9,136 
2,180 
2,042 

Number. 
1,143 
2,326 
2,009 
5,720 
2,007 
1,268 

Clay 

Polk            

Total 

36,  910 

80,  594 

26,  002 

14,  473 

STATISTICS  OF  LIVE  STOCK. 


625 


Livestock  in  lS9i  in  counties  of  North  Dakota  lying  mainli/  within  the  Bed  River  Valley. 


Counties. 

Horses. 

Cattle. 

Mu  les 

and 
asses. 

Sbeep. 

Swine. 

Number. 

Valu. 
ation. 

Number. 

Valu- 
ation. 

7,522 
16,  193 

9,335 
12, 160 
10,  405 
10,  280 

$369,  640 
758,  629 
571,  996 
629,  454 
535,  211 
501,  550 

12,  055 
14,  630 

9,834 

13,  251 
11,  533 
10, 147 

$136,  439 
148,  662 
107,  043 
162,  548 
133,  201 
118,243 

Number. 
5S5 
1,469 
952 
712 
267 
244 

Number. 
3,172 
5,621 
3,011 
10,  479 
6,716 
5,697 

Nvmber. 
2,945 
4,991 
3,  285 
3,  694 
4,114 
4,034 

Traill       

Grand  Forks 

"Walsh     

Total 

64,  895 

3,  366,  480 

71,  460 

796, 136 

4,229 

34,  696 

22,  907 

GEOXiOGIC  RESOURCES. 

The  grand  agricultural  capabilities  of  the  soil  having  been  stated,  as 
in  the  preceding  pages,  there  remains  little  to  be  added  relative  to  the 
more  strictly  geologic  resources  of  the  Red  River  Valley.  All  its  outcrops 
of  building  stone,  which  are  magnesian  limestone,  used  also  for  the  manu- 
facture of  lime,  are  situated  in  Manitoba.  Bricks  of  the  best  quality  are 
made  from  the  clayey  alluvium  which  borders  the  Red  River  along  nearly 
its  entire  course  after  it  turns  northward  at  Breckemidge  and  Wahpeton. 
These  constitute  the  complete  though  brief  list  of  the  commercially 
important  products  of  the  prairie  portion  of  Lake  Agassiz  which  belong 
to  economic  geology. 

GOLD. 

Within  the  wooded  portion  of  this  lactistrine  area  gold  occurs  and 
can  perhaps  be  profitably  mined  in  the  Archean  rocks  adjoining  the  Lake 
of  the  Woods  and  Rainy  Lake,  which  also  in  some  places  include  granite 
and  gneiss  valuable  for  building  purposes.  These  resources  have  been 
described  by  the  Canadian  and  Minnesota  Geological  Surveys,^  and  need 
not  be  further  noticed  here. 

'Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress,  1882-83-84,  pp.  1-22  K  (Report  on  tlie 
Gold  Mines  of  the  Lake  of  tlie  Woods,  by  Eugene  Coste) ;  Annual  Report,  new  series,  Vol.  I,  for  1885, 
pp.  140-151  CC  (Notes  on  Economic  Resources  of  the  Lali;e  of  the  Woods  Region,  by  Andrew  C.  Law- 
son).  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Twenty-third  Annual  Report,  for  1894,  pp.  36-105, 
with  map  (Preliminary  Report  on  the  Rainy  Lake  Gold  Region,  by  H,  V,  Wiuchell  and  U.  S,  Grant). 


MON    XXV- 


-40 


626  TUB  GLACIAL  LAKE  AGASSIZ. 

BUILDING    STONE. 

Quarries  of  magnesian  limestone  have  been  extensively  worked  at 
East  Selldrk,  Stonewall,  Stony  Mountain,  and  Little  Stony  Mountain,  partly 
for  lime-burning-,  but  also  in  large  amount  for  foundations,  bridges,  and 
buildings.  The  East  Selkirk  stone  is  beautifully  mottled  and  banded, 
and  is  easy  to  cut  when  first  quamed,  but  hardens  much  when  its  mois- 
ture dries  out.  It  contains  so  much  water  that  newly  quarried  l^locks  in 
winter  are  damaged  by  freezing;  but  after  drying  no  such  frost  fracture 
is  observed  where  this  rock  has  been  used  in  masonry.  By  exposure 
many  years  the  streaked  contrast  in  color  is  mostly  weathered  out,  the 
brown  portions  losing  their  darker  color.  The  Volunteers'  Monument  in 
Winnipeg  is  a  fine  example  of  the  adaptation  of  this  stone  for  ornamental 
purposes.  The  quarry  at  Stonewall,  situated  close  east  of  the  village,  has 
been  opened  to  an  average  depth  of  6  or  8  feet  on  an  area  about  15  rods 
square.  Inexhaustible  supplies  of  stone  of  the  most  durable  quality,  in 
many  portions  capable  of  being  quarried  in  blocks  of  large  dimensions,  out- 
crop there  and  at  Stony  Mountain,  and  have  been  much  used  for  building 
in  Winnipeg.  Similar  stone  has  been  slightly  quaiTied  on  the  northeast 
quarter  of  section  4,  township  15,  range  2  east,  on  land  of  Allen  Bristow,  9 
miles  north-northeast  of  Stonewall.  The  outcrop  of  Cretaceous  limestone 
on  the  Assiniboine,  in  section  36,  township  8,  range  11,  has  also  been 
quarried  in  small  amount. 

The  abundant  Archean  bowlders  of  granite,  gneiss,  and  schists  in  the 
till  or  glacial  drift  are  readily  collected  wherever  the  till  forms  the  surface, 
and  on  these  tracts  they  commonly  serve  the  immigrant  for  the  construc- 
tion of  foundations  of  farm  buildings  and  for  the  walls  of  cellars  and  wells. 

LIME. 

The  quarry  of  Little  Stony  Mouiitain  was  actively  operated  several 
years  ago  for  burning  lime,  a  spur  track  about  a  mile  long  being  laid  to  it 
from  the  Canadian  Pacific  Railway;  but  work  had  been  suspended  at  the 
time  of  my  survey  of  the  beaches  of  Lake  Agassiz  in  Manitoba,  in  1887. 

Besides  the  outcrops  of  the  bed-rock  which  thus  supply  lime,  it  is 
conveniently  obtained  by  collecting  and  burning  limestone  bowlders  that 


BUILDING  STONE,  LIME,  AND  BRICKS.  627 

occur  in  the  glacial  drift  throughout  all  the  prairie  district  of  Lake  Agassiz 
and  the  adjoining  country,  having  been  originally  derived  from  these  rock 
formations  and  distributed  by  the  currents  of  the  ice-sheet.  But  bowlders 
are  absent  from  the  lacustrine  and  alluvial  deposits  along  the  Red  River, 
and  from  the  Lake  Agassiz  deltas. 

BRICKS. 

Four  brickyards  in  St.  Boniface,  on  the  east  side  of  the  Red  River, 
opposite  to  Winnipeg,  produced  in  total  in  1887  about  4,000,000  bricks. 
This  business  began  to  be  extensively  developed  there  in  1880.  The  soil 
is  stripped  off  to  a  depth  of  2  feet,  beneath  which  the  next  2  or  3  feet  of 
yellowish,  horizontally  laminated,  somewhat  sandy  clay  is  used  for  brick- 
making.  It  requires  no  further  admixture  of  sand  for  tempering.  The 
bricks,  which  are  cream-colored  and  very  durable,  are  sold  at  $11  to  S12 
per  thousand,  loaded  on  the  cars  or  delivered  in  the  city  of  Winnipeg. 
Another  brickyard  in  St.  James,  close  southwest  of  Winnipeg,  makes  about 
1,500,000  bricks  yearly.  The  light  cream  color  of  these  bricks,  like  those 
of  Milwaukee  and  of  most  brickyards  in  Wisconsin,  Minnesota,  and  North 
Dakota,  is  due,  as  shown  by  Professor  Chamberlin,  to  the  calcareous  and 
magnesian  ingredients  of  these  glacial  clays,  derived  in  part  from  magnesian 
limestone  formations,  which  unite  with  the  iron  ingredient  to  form  a  light- 
colored  silicate,  instead  of  the  ferric  oxide  which  in  other  regions  destitute 
of  magnesian  limestone  gives  to  bricks  their  usual  red  color. 

In  the  Red  River  Valley  south  of  the  international  boundary  the  most 
important  localities  of  brickmaking  are  Moorhead,  Crookston,  and  Grrand 
Forks;  but  bricks  have  been  made  in  small  amount  at  numerous  other 
places,  as  Breckenridge,  St.  Hilaire,  and  Warren,  in  Minnesota,  and  Grafton, 
Cavalier,  and  Pembina,  in  North  Dakota. 

A  large  business  in  brickmaking  is  done  at  Moorhead  by  Lamb  Bros., 
who  began  in  1874;  Kruegel  &  Truitt,  who  began  in  1878;  and  John 
Early  and  John  Gr.  Bergquist,  who  began  in  1881.  Their  product  in  1887 
was  as  follows:  Lamb  Bros.,  about  2,000,000;  Kruegel  &  Truitt,  also 
about  2,000,000;  Mr.  Early,  700,000;  and  Mr.  Bergquist  125,000.  The 
black  soil  is  removed  to  the  depth  of  1  foot  or  IJ  feet;  the  next  1  to  2  feet 


628  THE  GLACIAL  LAKE  AGASSIZ. 

of  the  alluvial  clay  is  used  for  brickmaking,  its  color  being  dark  above  and 
yellowish  beneath;  the  lower  continuation  of  this  deposit  is  imsuited  for 
this  use  because  of  limy  concretions.  No  sand  is  required  for  tempering. 
Sand  needed  for  mortar  is  brought  from  Muskoda  at  the  cost  of  about  $3 
per  cubic  yard.  The  bricks  are  cream-colored  and  of  very  good  quality, 
selling  at  about  $10  per  thousand.  Oak  wood,  used  for  fuel,  costs  $5 
per  cord. 

The  brickyards  of  Crookston,  owned  by  Non-is  &  McDonald,  W.  A. 
Norcross,  and  G.  Q.  Erskine,  supply  2,000,000  to  3,000,000  bricks  yearly, 
which  bring  an  average  price  of  $10  per  thousand  at  wholesale,  loaded 
on  the  cars.  At  Mr.  Erskine's  yard,  on  the  south  side  of  the  Red  Lake 
River,  a  thickness  of  13  feet  of  clay  is  used,  lying  next  below  the  superficial 
2  or  3  feet  of  black  soil,  which  is  removed.  The  more  sandy  lower  part 
of  the  clay  is  mixed  with  the  upper  part,  by  which  the  whole  is  rightly 
tempered. 

In  Grand  Forks  brickmaking  has  been  carried  on  by  J.  S.  Bartholo- 
mew since  1880,  his  product  in  1887  being  1,200,000.  The  upper  foot 
of  soil  is  stripped  off  and  the  next  7  feet  of  clay  are  used,  requiring  no 
intermixture  of  sand. 

SALT. 

The  description  of  the  artesian  wells  of  this  district  given  in  the  pre- 
ceding chapter  has  included  nearly  all  that  needs  to  be  stated  concerning 
its  saline  well  water  and  springs.  In  the  early  times,  when  the  Hudson 
Bay  Company's  trading  posts  and  the  Selkirk  colonists  comprised  all  the 
white  inhabitants  of  the  region,  the  expense  of  importation  of  salt  was 
much  greater  than  now,  and  considerable  quantities  of  it  were  yearly  made 
by  evaporation  of  the  water  of  salt  springs.  One  of  these  springs  from 
which  much  salt  was  made  for  the  Hudson  Bay  Company  is  situated  in 
the  channel  of  the  South  Branch  of  Two  Rivers,  about  IJ  miles  above  its 
junction  with  the  North  Branch  and  some  6  miles  west  of  Hallock.  It  is 
exposed  only  when  the  river  runs  low,  and  in  such  portions  of  the  summers 
the  work  of  salt-making  was  done. 


SALT  AND  LIGNITE.  629 

The  principal  product  of  salt  then  used,  in  this  disti-ict,  however,  was 
from  brine  springs  and  wells  on  the  low,  flat  land  bordering  the  west  side  of 
the  south  end  of  the  southeast  arm  of  Lake  Winnipegosis.  This  brine  is 
so  strong,  according  to  Hind,  that  30  gallons  yield  a  bushel  of  salt.  The 
product  in  1874,  as  reported  by  Spencer,  was  about  500  bushels,  sodium 
chloride  forming  95  per  cent  of  the  manufactured  salt.^ 

Brine  about  a  third  as  strong  as  that  of  the  salt  wells  of  the  Saginaw 
district  in  Michigan  was  found  by  the  artesian  wells  of  Humboldt,  Minn., 
and  Rosenfeld,  Manitoba  (pages  537  and  538).  Though  very  pure  brine, 
it  can  not  be  utilized  in  competition  with  the  salt  manufacture  in  Michigan, 
especially  when  the  cost  of  fuel  at  the  salt  works  there,  using  refuse  from 
sawmills,  is  almost  nothing,  while  on  this  prairie  tract  its  cost  would  be 
about  $5  per  cord.  A  sample  of  salt  made  from  the  Humboldt  well  was 
exhibited  at  the  New  Orleans  Exposition  in  1884-85.^ 

LIGNITE. 

Thin  layers  of  lignite  coal,  seldom  exceeding  a  foot  in  thickness,  are 
contained  in  the  Cretaceous  shales,  probably  belonging  mostly  to  the  Fort 
Benton  formation,  which  are  scantily  preserved  beneath  the  tliick  drift 
sheet,  and  are  occasionally  exposed  in  outcrops,  throughout  the  western 
two-thirds  of  Minnesota.  Here  and  there  fragments  of  lignite  derived  from 
these  beds  are  found  quite  plentifully  in  the  till,  and  also  sometimes  in 
gravel  and  sand  deposits  of  the  modified  drift,  so  that  hundreds  of  little 
pieces,  up  to  3  or  4  inches  in  length,  and  very  rarely  a  larger  mass,  are 
obtained  in  digging  a  well  or  cellar,  or  may  be  found  in  the  ravines  of 
streams  or  on  lake  shores.  But  more  commonly  a  well  dug  30  or  40  feet 
deep  in  the  till  encounters  none  or  no  more  than  two  or  three  of  these 
fragments.  Where  they  abound  in  the  drift.  Cretaceous  shales  bearing 
lignite  had  been  doubtless  eroded  by  the  ice-sheet  within  a  moderate 
distance  to  the  north,  and  remnants  of  them  may  still  exist. 

'H.  Y.  Hinil,  Narrative  of  the  Canadian  Exploring  Expeditions,  London,  18(iO,  A'^ol.  II,  pp.  43-45. 
J.  W.  Spencer,  Geol.  and  Nat.  Hist.  Survey  of  Canada,  Report  of  Progress  for  1874-75,  p.  69. 

=  N.  H.  Wiuchell,  Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  TUirteenth  Annual  Report,  for  1884, 
pp.  41-46. 


630  THE  GLACIAL  LAKE  AGASSIZ. 

Witliiu  the  area  of  Lake  Agassiz  lignite  fragments  have  been  thus 
found  plentifully  in  many  localities,  among  which  the  following  may  be 
specially  noted:  In  digging  a  cellar  close  south  of  the  Mustinka  River,  in 
section  32,  township  127,  range  47,  near  its  entrance  into  the  north  end  of 
Lake  Traverse;  in  wells  near  Tintah  and  at  Campbell,  Minn.;  in  a  ravine 
which  intersects  the  Herman  and  Norcross  beaches,  in  sections  32  and  31, 
Keene,  8  miles  north  of  Muskoda,  Clay  County;  in  the  sand  of  the  artesian 
wells  on  the  Lockhart  Farm,  Norman  County,  at  the  depth  of  141  to  157 
feet;  similarly  in  sand  between  161  and  165  feet  below  the  surface  in 
artesian  wells  at  Carman,  Polk  County;  along  the  channel  of  the  South 
Branch  of  Two  Rivers,  in  the  southwest  part  of  township  160,  range  44,  at 
a  distance  of  a  half  mile  to  2  miles  east  of  its  crossing  by  the  Roseau  Lake 
trail,  as  reported  by  Mr.  Charles  Hallock  and  Maj.  vS.  Holcomb,  the  largest 
piece  found  being  about  1|  feet  square  and  4  inches  thick;  and  on  the 
Roseau  River,  in  Manitoba,  about  20  miles  east  of  Dominion  City.  Pieces 
of  lignite  are  somewhat  frequent  on  portions  of  the  shores  of  Red  Lake, 
Lake  Winnebagoshish,  and  Namekan  Lake,  the  last  lying  on  the  interna- 
tional boundary,  next  southeast  of  Rainy  Lake.  They  also  occur  in 
gravel  beds  of  the  Pembina  delta  of  Lake  Agassiz,  having  been  especially 
noticed  at  the  springs  in  the  south  bluif  of  the  Pembina  River,  2  miles 
south  of  Walhalla. 

It  is  not  advisable,  however,  that  any  search  should  be  made  for  dis- 
covery of  lignite  beds  in  remnants  of  the  Cretaceous  strata  still  existing 
within  this  lacustrine  area ;  for,  while  the  lignite  is  of  poor  quality  for  fuel, 
all  its  numerous  known  deposits  thus  occurring  in  several  counties  in  Min- 
nesota, and  on  the  Sheyenne  and  in  the  Turtle  Mountain,  North  Dakota, 
are  too  thin  to  be  worked.  On  the  upper  portion  of  the  Souris  River,  in 
Manitoba  and  North  Dakota,  from  the  vicinity  of  Minot  northward,  and  on 
the  Northern  Pacific  Railroad,  40  miles  west  of  Bismarck,  beds  of  similar 
lignite,  but  belonging,  as  in  Turtle  Mountain,  to  the  Laramie  series,  the 
highest  of  the  Cretaceous,  ranging  up  to  8  feet  in  thickness,  have  been  suc- 
cessfully mined,  their  product  being  used  for  fuel  by  many  settlers  in  this 
vast  prairie  region. 


GNITE,  NATUKAL  GAS,  AND  WATEK  i^OWEE.  631 

NATURAL    GAS. 

A  few  years  ago,  after  the  wonderful  discoveries  of  natural  gas  in 
Pennsylvania  and  Ohio,  many  people  held  the  delusive  hope  and  belief 
that  it  could  be  obtained  in  valuable  amount  by  boring  deeply  in  almost 
any  locality  or  geologic  formation.  In  the  Red  River  Valley  this  hope  was 
fostered  by  the  occurrence  of  combustible  gas  issuing  from  wells  in  the 
drift  in  Arthur  Township,  Traverse  County,  at  Argyle,  and  in  section 
10,  Wanger,  Marshall  County,  Minn.,  and  near  Argusville  and  Gardner,  at 
Hillsboro,  near  Cummings,  and  near  Mayville,  in  North  Dakota.  These 
flows  of  gas,  though  readily  ignited  and  burning  for  a  time  with  consider- 
able flame,  are  of  small  amount,  and  are  probably  derived  from  fragmentary 
lignite  and  other  vegetal  matter  very  scantily  contained  in  the  drift. 

To  test  the  questions  whether  either  artesian  water  or  gas  could  be 
obtained  from  the  rock  formations  underlying  the  drift  at  Moorhead,  a  well 
was  bored  there  in  1889  to  the  depth  of  1,760  feet  (page  556).  Below  the 
depth  of  365  feet  this  boring,  which  was  done  at  public  cost  by  order  of 
the  city  government,  was  in  Archean  granitoid  and  gneissic  rocks,  in  which 
a  large  expenditure  was  wasted  after  the  State  geologist.  Prof  N.  H.  Win- 
chell,  had  infoi'med  the  mayor  that  the  samples  of  the  drillings  forbade 
"any  hope  of  obtaining  artesian  water  or  other  product  of  value." ^  It  is 
well-nigh  certain  that  nowhere  in  this  lacustrine  area  can  either  lignite  or 
natural  gas  be  found  in  such  quantity  as  to  be  practically  utilized. 

WATER   POWER  AND  MAJfUFACTURES. 

Very  valuable  water  powers,  some  of  which  are  now  used,  while  many 
others  have  not  been  improved  nor  surveyed,  exist  on  the  head  stream  of 
the  Red  River  above  Breckenridge,  on  its  tributary,  the  Pelican  River, 
on  the  Red  Lake  River  and  its  tributary,  the  Clearwater,  on  the  Rainy  and 
Winnipeg  rivers,  at  the  Grand  Rapids  of  the  Saskatchewan,  and  on  the 
Nelson.  There  are  also  small  and  less  constant  water  powers,  several  of 
which  are  utilized,  on  the  Buffalo  and  Wild  Rice  rivers,  in  Minnesota,  on 
the  Sheyenne,  Goose,  Turtle,  Forest,  Park,  and  Pembina  rivers,  in  North 
Dakota,  and  on  the  Souris  and  Assiniboine  rivers,  in  Manitoba. 

'  Geol.  and  Nat.  Hist.  Surrey  of  Jliniiesota,  Ttiilletiu  No.  5,  1889 :  Natural  Oas  in  Miuuesota,  p.  .S9. 


632  THE  GLACIAL  LAKE  AGASSIZ. 

The  Red  River  (pages  54-56)  has  four  improved  powers,  varying  in 
head  from  10  to  15  feet,  in  the  city  of  Fergus  Falls.  Moderate  expense 
in  the  construction  of  dams  to  make  Ottertail,  Rush,  and  Pine  lakes  reser- 
voirs, filled  in  spring  several  feet  above  their  present  level  and  drawn  down 
in  time  of  drought,  would  nuich  increase  the  available  water  power  of 
this  river  at  Fergus  Falls  and  along  all  its  extent  from  Ottertail  Lake  to 
Breckenridge.  In  this  distance  the  river  falls  nearly  375  feet,  averaging  6 
feet  per  mile.  Its  bed  is  the  hard,  stony  clay  of  the  glacial  drift,  affording 
a  good  foundation  for  dams,  and  along  most  of  this  distance  the  sloping 
river  banks  permit  the  water  to  be  carried  in  canals  so  as  to  furnish  any 
amount  of  head  desired  for  milling  purposes.  On  the  west  the  wheat  of  the 
Red  River  Valley,  and  on  the  east  oak,  maple,  ash,  and  pine  timber,  invite 
the  further  utilization  of  this  magnificent  water  power.  ^ 

A  series  of  lakes  that  are  the  sources  of  the  Pelican  River,  tending  to 
equalize  its  flow  in  wet  and  dry  seasons,  and  the  descent  of  this  stream 
about  200  feet  from  Lake  Lizzie  to  its  mouth,  with  a  channel  and  banks  of 
glacial  drift,  make  its  water  power  almost  equally  valuable  with  that  of  the 
Red  River. 

Large  lakes  which  serve  as  reservoirs  also  give  a  high  degree  of  con- 
stancy to  the  water  power  of  the  Clearwater  and  Red  Lake  rivers  (pages 
52-54),  already  partially  utilized  at  Red  Lake  Falls  and  Crookston,  and 
especially  to  the  power  of  the  falls  of  the  Rainy  River  at  Koochiching 
and  Fort  Frances  (page  50),  and  to  the  many  rapids  and  waterfalls  of 
the  Winnipeg  River  (pages  51,  52).  These  streams  will  doubtless  some 
day  become  the  sites  of  large  manufacturing  cities,  where  the  wheat  of  the 
prairies  will  be  made  into  flour  and  the  timber  of  the  adjoining  forests  will 
be  manufactured  into  lumber,  paper,  furniture,  and  various  wooden  wares. 
While  agriculture  will  be  the  leading  occupation  in  the  prairie  region  of 
Lake  Agassiz,  more  diverse  industries  will  grow  up  in  the  wooded  country 
of  its  eastern  and  northern  portions. 

'  For  details  of  the  Trater  power  of  the  Red  River  and  its  tributaries,  see  "The  water  power  of 
the  Northwef.t"  (pp.  104),  by  James  L.  Greenleaf,  iu  Tenth  Census  of  the  United  States,  1880,  Vol. 
XVII. 


APPENDIX  A. 

COURSES  OF  GLACIAL  STEI^. 

The  following-  table  of  glacial  stii.Tj  iu  the  region  of  Iludsoii  Bay  and  Lake 
Superior  and  westward  shows  the  directions  of  the  currents  of  the  ice-sheet  within 
the  basin  of  Lake  Agassiz  and  upon  the  country  where  it  lay  as  the  barrier  or  dam 
of  this  lake.  The  notes  are  derived  chiefly  from  the  reports  of  the  geological  and 
natural  history  surveys  of  Canada  and  of  Minnesota,  and  are  all  reduced  to  refer 
to  the  true  or  astronomic  meridians.  Unless  they  are  otherwise  credited,  the  obser- 
vations ill  British  America  are  by  Dr.  Robert  Bell,  and  in  Minnesota  and  ISTorth 
Dakota  by  the  present  writer. 

The  lobation  of  the  ice-sheet  in  this  basin,  its  diverse  and  prolonged  courses  of 
transportation  of  drift,  which  deijeuded  on  the  glacial  currents  producing  the  strire, 
and  the  intersection,  in  some  localities,  of  two  or  more  sets  of  striation,  have  been 
considered  on  pages  129-131.  Besides  the  citations  on  these  subjects  there  given, 
reference  may  be  made  to  my  recent  papers  on  remarkably  deflected  striation  in 
Somerville,  Mass.,^  and  in  the  vicinity  of  Two  Harbors,  Duluth,  and  Carlton,  Minu.^ 

Hudson  Strait  and  Bay. 
Hudson  Strait: 

Port  Burwcll,  10  miles  southwest  from  Cape  Chudleigh S.  85°  E. 

Ashes  lulet,  on  the  north  side  of  tlie  strait,  about S.  65^  E. 

Cape  Prince  of  AVales,  on  the  south  side,  opposite  to  the  last E.  to  N.  70^  E. 

South  part  of  Nottingham  Island S_  ^qo  j;_ 

Digges  Island,  off  Cape  Wolstenholme jj.  550-750  jj 

Ottawa  Islands,  in  the  northeast  part  of  Hudson  Bay N.  75°  E.,  N.  40°-20°  E.,  and  N.  5°  W. 

East  coast  of  Hudson  Bay : 

Northern  part,  successively,  proceeding  southward NE.  N.  audNW. 

From  Cape  Dufferin  southward  to  Hopewell  Head  and  the  most  northern  of  the  Nas- 
tapoka  Islands,  in  latitude  58°  to  57°  N.,  near  the  middle  of  the  east  side  of  Hudson 

Bay,  numerous  localities S.  70°,  60°,  and  35°  W. 

[It  is  probable  that  the  first  two  of  these  courses  record  the  direction  of  the 

ice-flow  during  the  time  of  maximum  depth  and  area  of  the  ice-sheet,   or  durino- 

a  somewhat  later  stage ;  and  that  the  last  belongs  to  the  time  of  final  melting  of 

the  ice.] 

Thence  southward  to   the  entrance  of   Richmond  Gulf,  numerous  localities,  mostly 

between S.  65°-75°  W.  and  N.  75°  W. 

But  in  two  localities,  probably  a  later  glaciation S.  350^50  W". 

Cairn  Mountain  Island,  Eichuiond  G  nlf,  several  localities,  mostly N.  60°-70°  W. 

But  in  one  place  varying  from  this  to g.  450  \y 

'  Proc.  Boston  Soe.  Nat.  Hist.,  Vol.  XXVI,  pp.  33-42,  March  15, 1893. 

^Geol.  and  Nat.  Hist.  Survey  of  Minnesota,  Twenty-second  Annual  Report,  for  1893,  pp.  31^3,  with 
map  of  the  glacial  geology  (striic,  retrcatal  moraines,  etc.)  of  northern  Minnesota. 

633 


634  THE  GLACIAL  LAKE  AGASSIZ. 

East  coast  of  Hudson  Bay — Continued. 

From  Kichmoud  Gulf  and  Little  Wliale  Eiver  soutliward  to  Esquimaux  Harbor,  many 

localities N.  80°  W.  to  W. 

Thence  to  Red  Head,  57  miles  northeast  of  Cape  Jones,  eight  localities W.  to  S.  75^^  W. 

And  one  locality; S.55°  W. 

Red  Head  Island N.70^"  W. 

Thence  southward  to  40  miles  south  of  Big  River,  many  localities S.  40'^-60°  and  70  W. 

But  ou  the  southwest  extremity  of  Long. Island,  near  Cape  Jones,  striiE  bear  in  every 

direction  from S.  70^  W.,  around  by  SW.  and  S.,  to  S.  40^'  E. 

The  two  prevailing  directions  are  about S.45'^  W.  and  S.  15^  E. 

The  former  seems  probably  the  older,  but  perhaps  deflected  to  the  south  from  the 
direction  of  the  glacial  current  when  the  ice-sheet  was  thickest;  and  the  latter, 
with  further  deflection  southeastward,  may  belong  to  the  closing  stages  of  the 
Glacial  period.     An  island  off  the  southwest  point  of  Long  Island  has  three  sets 

of  glacial  stria- S.  60°  W. ,  S.  40"  W.,  and  S.  20°  E. 

From  40  miles  south  of  Big  River  southward  along  the  east  coast  of  the  south  half  of 

James  Bay,  mauy  localities S.  30°-55°  W. 

But  in  one  locality,  about  3  miles  northwest  of  the  Paint  Hills,  three  sets  of  glacial 

stria;  occur,  bearing N.  7!i°  W.,  S.  55°  W.,  and  S.  30°  W. 

The  first  probal>ly  records  approximately  the  course  of  glaciation  here  when  the  ice 
attained  its  greatest  area,  lielonging  thus  to  a  striation  whicli  was  chiefly  ett'aced 
by  a  later  glacial  movement  to  the  southwest  during  the  departure  of  the  ice-sheet. 
Again,  at  the  Paint  Hills  two  sets  of  glacial  stria-  are  found,  bearing. .  S.  75°  W.  and  S.  35°  W. 

And  ou  Governor.-;  Island,  at  the  mouth  of  Eastmain  River,  the  course  is S.  75°  W. 

In   the  country  east    of    Hudson  Bay,  extending  from    Richmond  Gulf   southward    and 
drained  by  the  Clearwater,  Great  Whale,  and  Big  rivers,  forty-nine  localities  (A.  P. 

Low) S.  50°  W.  to  N.  (50.  W. 

Excepting  two  places  which  have  intersecting  striiB,  namely — 

For  the  first N.  80°  W.  and  N.  3.5°  W. 

For  the  second N.  68°  W.  and  N.  50°  W. 

But  in  a  majority  (thirty-six)  of  the  localities  in  Mr.  Low's  list  the  l)eariugs  range 

between S.  60°  W.  and  W. 

Marble  Island,  northwest  part  of  Hudson  Bay S.  15°-25°  E. 

West  coast  of  Hudson  Bay : 

East  side  of  the  mouth  of  Churchill  River S.  5°  E. 

Two  and  a  half  miles  east  from  the  last S.  20°  W. 

Five  miles  east  from  the  mouth  of  Churchill  River S.  15°  E. 

Region  of  the  Churchill  and  Nelson  rivers,  Lake   Winnipeg,  and  southwest  to  the  Assiniboine. 

Churchill  Eiver: 

At  Fort  Churchill S.  30^-40°  W. 

Four  miles  below  the  mouth  of  the  Little  Churchill  River S.  20°  W.  and  S.  80°  W. 

Six  and  11  miles  above  the  mouth  of  the  Little  Churchill  River S.  10°-15°  W. 

Little  Churcliill  River : 

Three  localities.  4,  13,  and  18  miles  below  Waskalowaka  Lake,  respectively 

S.  40°  W.,  S.  80°  W.,  and  N.  85°  W. 

Outlet  of  Lower  Recluse  Lake,  various  directions  from S.  15°  W.  to  S.  50°  W. 

Also ^^■ 

Eagle  Rapid,  2  miles  in  a  straight  line  below  the  last,  two  sets,  both  distinct. . .   S.  20°  W.  and  W. 
[The  courses  to  the  west,  or  nearly  so,  probably  mark  the  motion  of  this  part 
of  the  ice-sheet   during   the  time   of  its   greatest   depth   and   extent,  while  the 
southerly  courses  show  its  deflected  motion  during  the  final  melting.] 
Along  the  Nelson  Eiver : 

Third  Limestone  Rapid,  100  miles  by  the  course  of  the  river  above  its  mouth S.  30°-50°  E. 

Broad  Rapid,5  miles  long,  11  to  16  miles  above  the  last,  mostly S.50°  W. 

Also S.  15°  W.  and  S.  55°-75°  W. 

Thence  to  Middle  Gull  Eapid,  numerous  localities S.  55°-80°  W. 


COURSES  OF  GLACIAL  STRI^.  635 

Along  the  Nelson  River — Continued- 
Upper  Gull  Rapid,  and  tlieuce  to  the  middle  portion  of  Split  Lake,  numerous  local- 
ities   N.85°-75°W. 

Southwestern  part  of  Split  Lake,  two  localities S.  85°  W. 

Chain  of  Rocks  Rapid,  3  miles  above  Split  Lake,  one  set,  probably  the  older S.SS^  W. 

The  other S.  10°  E. 

On  Grass  River,  tributary  to  the  Nelson  River  from  the  west,  a  few  miles  above  Split 

Lake,  numerous  localities S.  85°  W.  to  W. 

But  in  one  place,  at  the  outlet  of  Witchai  (Stinking)  Lake N.  75°  W. 

Between  Split  Lake  and  Sipi- wesk  Lake,  numerous  localities,  mainly S.  55°-75°  W. 

Aud  occasionally "• 

Sipi- wesk  Lake,  outlet  and  northeastern  part,  mostly S.  70°-75°  W. 

Also,  in  numerous  localities S.45°-65°  W. 

Sipi-wesk  Lake,  average  course  throughout  the  southwestern  half  of  the  lake S.  55°-60°  W. 

But  in  some  places N.  85°  W. 

Southwest  extremity  of  Sipi-wesk  Lake ^S.  65°  W. 

From  Sipi-wesk  Lake  to  the  outlet  of  Pipestone  Lake,  six  localities S.  55°-65°  W. 

Pipestone  aud  Big  Reed  Lakes  and  vicinity,  five  localities S.40°-55°  W. 

Along  the  usual  boat  route  from  Hudson  Bay,  by  Hayes  and  Hill  rivers,  to  Lake  Winnipeg : 

Six  miles  below  The  Rock,  Hill  River S.  12°  E. 

The  Rock,  Hill  River S.  10°  E. 

Dr.  Bell  reports  also  at  this  locality  another  and  older  set  of  striai N.  79°  W. 

Borwick's  Fall,  and  1  mile  above  White  Mud  Fall,  Hill  River,  both  within  a  few  miles 

southwest  from  The  Rock,  respectively S.  18°  W.  and  S.  28°  W. 

Knee  Lake,  numeroua  localities S.  35°-60°  W. 

From  Knee  Lake  to  Pine  Lake,  seven  localities S.  45°-60-  W. 

From  Pine  Lake  and  Molsons  Lake  to  Great  Playgreen  Lake,  many  localities S.  35°-60°  W. 

Arouud  Gods  Lake,  southeast  of  the  foregoing  route,  140  to  180  miles  east-northeast  from  the 

north  end  of  Lake  Winnipeg,  many  localities  (Cochrane)..  S.  to  S.  52°  W.,  mostly  S.  15°-40°  W. 

But  in  two  localities ----   S.80°  W. 

Between  Jackson  Bay,  on  Oxford  Lake,  and  the  southern  part  of  Gods  Lake,  seven  localities 

(Cochrane) S.28°^0°W. 

Around  Island  Lake,  about  40  miles  south  of  Gods  Lake,  many  localities  (Cochrane) . . .  S.  10°-36"  W. 
Between  Hudson  Bay  aud  Lake  Winnipeg,  along  the  Severn,  Fawn,  Poplar,  and  Berens 

rivers,  on  almost  all  exposed  surfaces  (A.  P.  Low),  generally SW. 

[The  variations  are  only  a  few  degrees  from  this  on  either  side.] 

Mouth  of  Lake  Winnipeg  and  its  vicinity,  several  localities S-  40°-45°  W. 

East  shore  of  Lake  Winnipeg: 

Spider  Islands,  on  the  adjacent  mainland,  and  at  the  Shoal  Islands,  about  30  and  45 

luilea  south  from  the  north  end  of  the  lake S.  30°-40°  W. 

Poplar  Point,  4  miles  southeast  of  Poplar  Point,  and  opposite  to  Georges  Island,  a  few 

miles  farther  southeast S.  30°-35°  W. 

Four  localities  near  the  mouth  of  Berens  River,  halfway  from  the  north  to  the  south  end 

of  the  lake S  57°-60o  W. 

Near  the  mouth  of  Berens  River  (Pantou) SW.  and  SSW. 

East  side  of  Berens  or  Swampy  Island  (Panton) SW. 

Of  this  island  Mr.  J.  B.  Tyrrell  writes :  "The  general  direction  of  striation  is S.  52°  W. 

"While  another  set   of   8tri;B   was  found   to  occur  under  a  mass   of   pebbles  and 

bowlders,  bearmg '^-  ^^    •^• 

Rabbit  Point,  near  the  Narrows S.  48°  W. 

Black  Bear  Island,  also  near  the  Narrows  (Panton) SSW. 

Intersected  by  other  glacial  striiu,  bearing SSE. 

[The  latter,  agreeing  nearly  in  direction  with  stria;  observed  on  Swampy  Island, 
on  the  Winnipeg  River  above  Lac  du  Bonnet,  around  the  south  end  of  Lake  Winui- 
pegosis,  on  lakes  Manitoba  and  St.  Martin,  at  Stonewall,  Stony  Mountain,  and 
Little  Stony  Mountain,  near  Winnipeg,  and  on  the  Assiniboine  River,  appear  to 
l)elong  to  the  basal  portion  of  the  divergent  glaci.al  current  which  continued  south 
and  southeast  in  the  Minnesota  and  Dakota  lobes  of  the  ice-sheet.] 


636  THE  GLACIAL  LAKE  AGASSIZ. 

East  shore  of  Lake  Winnipeg — C'ontinuetl. 

Between  The  Narrows  and  the  mouth  of  Winnipeg  River,  numerous  localities S.40°-i5°  W. 

Winnipeg  River,   above   Lac  du   Bonnet  to   tlie  Whitemouth    River   (Tyrrell),   apjiroxi- 

mately SSE.  and  SW. 

The  following,  to  Lake  St.  Martin,  inclusive,  are  from  a  paper  by  Mr.  J.  B.  Tyrrell, 
of  the  Geological  and  Natural  History  Survey  of  Canada,  entitled  "Pleistocene  of 
the  Winnipeg  basin,"  Am.  Geologist,  Vol.  VIII,  pp.  19-28,  July,  1891: 

Lake  Winnipeg : 

Northwest  shore,  "from  William  River  to  the  mouth  of  the  Saskatchewan,"  average S.  2°  W. 

West  shore,  at  mouths  of  St.  Martin  and  Fisher  rivers,  probably  about S. 

Cedar  Lake : 

East  side S.  18°  W. 

West  side,  near  mouth  of  the  Saskatchewan S.  39^  W. 

Lake  Wiuuipegosis: 

Northeastern  angle S.  23°  W. 

A  little  farther  down  the  east  shore S.  9°  W. 

Around  Its  south  end S.  2°-13°  E. 

Dawson  Bay S.  42°-58o  W. 

Red  Deer  River S.68°-78°  W. 

SwiinLake S.48°-53°  W. 

Lake  Manitoba : 

Northwest  arm Southward. 

East  shore,  near  Steep  Rock  Point S.  8'^-13°  E. 

Lake  St.  Martin,  granite  islands S.  33°  E. 

Stonewall,  in  many  places  (Panton,  Upham) S.  20°-2,5"  E. 

Stony  Mountain  (Panton,  Upham) S.  20°-25°  E. 

Little  Stony  Mountain  (Upham) S.  25^  E. 

Assiniboiue  River : 

Sectiou  36,  township  8,  range  11,  in  three  places  (Upham) S.  4°-8°  W. 

And  in  one  jilace S.  10°  E. 

Section  23,  township  9,  range  10  (Tyrrell) S.  38°  E. 

Atliaiasca  River  and  Lake,  Wollaston  and  Eeindeer  lakes,  and  southward  to  Cumberland  House. 

Mountain  Portage,  Athabasca  River,  7  miles  above  the  mouth  of  Clearwater  River S.  54°  E. 

Or  more  probably N.  54°  W. 

Fort  Chipewyau,  near  the  mouth  of  Lake  Athabasca,  also  1  mile  west  and  8  miles  southwest 

of  Fort  Chipewyan S.78°-83°  W. 

The  following  observations,  to  Cumberland  House,  are  by  Mr.  A.  S.  Cochrane,  and 
are  communicated  by  Dr.  Robert  Bell : 

North  shore  of  Lake  Athabasca : 

Ten  miles  north  from  the  Burntwood  Islands : S.81°  W. 

Twenty  miles  west  of  Black  Bay S.  61°  W. 

Halfway  from  the  west  to  the  east  end  of  the  lake S.  43°  W. 

Twenty  miles  west  of  the  Hudson  Bay  Company's  post  at  Fond  du  Lac  ...   S.  21^,  27°,  and  31°  W, 

Hudson  Bay  Company's  post.  Fond  du  Lac,  50  miles  west  from  the  east  end  of  the  lake.  S.  53°  W. 
On  the  western  outlet  of  Wollaston  (Hatchet)  Lake,  15  miles  east  from  its  mouth  at  the 

east  end  of  Athabasca  Lake S.  85°  W. 

Junction  of  Porcujiine  River  with  the  western  outlet  of  W^oUaston  Lake,  50  miles  east  of 

Athabasca  L.ake S.  75°  W. 

North  shore  of  Wollaston  Lake,  halfw.ay  between  its  western  and  eastern  outlets S.27°  W. 

Jackfish  Lake,  about  halfway  between  Wollaston  and  Reindeer  lakes,  by  way  of  Hatchet 

Lake  River S.  17°  W. 


COUESES  OF  GLACIAL  STKI^.  637 

North  end  of  Reindeer  Lake: 

Average  of  numerous  observations S.31°  W. 

Mouth  of  Hatchet  Lake  River S.  17°  W. 

East  shore  of  Reindeer  Lake : 

Porcupine  Point S.  24°  W. 

Halfway  from  the  north  to  the  south  end  of  the  lake S.  18°  W. 

South  end  of  Reindeer  Lake,  and  ou  its  outlet S.  18°  W. 

Churchill  River: 

Near  Frog  Portage,  110  miles  north-northwest  of  Cumberhiud  House S.  40°  W. 

At  a  small  lake  10  miles  east  from  the  mouth  of  Isle  a  la  Crosse  Lake S.  18°  W. 

Ou  the  canoe  route : 

Seventy  miles  north  of  Cumberland  House R.  16°  and  26°  W. 

Fifty-five  miles  north  of  Cumberland  House S.  26°  W. 

[As  on  the  lower  part  of  Churchill  River,  before  noted,  the  more  westerly 
courses  of  this  list  are  believed  to  indicate  the  glacial  motion  when  the  ice  had  its 
maximum  depth,  or  nearly  that,  continuing  probably  through  the  greater  part  of 
the  period  of  glaciation;  and  the  southward  currents  seem  referable  to  deilect:ii>u 
during  the  recession  of  the  boundary  of  the  ice-sheet,  most  of  the  earlier  westward 
striai  being  thereby  eifaced.] 

From  Hudson  Bay  to  Lake  Superior  and  the  Lake  of  the  Woods. 

On  the  route  of  Dr.  Bell  from  James  Bay  to  Lake  Huron,  commonly S.5°  E;.  to  S.  5    W. 

Rarely  varying  to S.  25°  E. 

Between  James  Bay  and  the  east  end  of  Lake  Superior: 

From  Long  Portage  of  the  Missinaibi  River  to  Mattagami  Lake,  both  belonging  to  the 

Moose  River  system,  mostly SSW. 

Wasquagami  Portage,  Missinaibi  River,  two  sets S.  15"  W.  and  S.  60°  E. 

[The  last  is  doubtless  a  local  deflection,  belonging  to  the  time  when  the  ice- 
sheet  was  being  melted  away.] 

Missinaibi  River,  east  of  Brunswick  Lake S.  15°  E. 

Around  Mattagami  Lake S.  30°-65°  W. 

Lake  Manitowick,  on  Michipicoten  River S.  30°  W. 

Long  Portage  of  the  Michipicoten  River,  6  miles  east  of  its  mouth S.  40°  W. 

North  shore  of  Lake  Superior : 

Falls  of  St.  Mary,  and  thence  20  miles  north  (Agassiz) SSE. 

Twenty-five  miles  north  of  the  Falls  of  St.  Mary,  and  thence  to  the  northeast  angle  of 

the  lake,  7.5  miles  east  of  St.  Iguace  Island,  many  localities  (Agassiz) S. 

Fifty  miles  east  of  St.  Ignaee  Island  (Agassiz) SSW. 

St.  Ignaee  Island,  and  the  same  25  miles  east  (Agassiz) S. 

Southwest  side  of  Nipigon  Bay  (Agassiz) SSW. 

Islands  in  Thunder  Bay  (Agassiz) SW. 

Between  Thunder  Bay  and  Pigeon  River  (Agassiz) S. 

Isle  Royale,  Lake  Superior,  numerous  localities  (Desor) S.  20°-75°  W. 

Along  the  Pic  River,  tributary  to  Lake  Superior S.  20°-30°  W. 

Kenogami  or  Long  Lake,  at  the  head  of  the  Kenogami  River,  tributary  to  Albany  River, 

many  localities S.  to  S.  25°  W. 

["The  grooving  is  as  well  marked  on  the  tojjs  of  the  highest  hills  as  iu  the 
lake  valleys."] 

In  the  country  northwest  of  Kenogami  or  Long  Lake,  several  localities S.  30°-40°  W. 

Along  the  Kenogami  River,  mostly S.30°-.50°  W. 

But  varying  to , S.  and  S.  60°  W. 

Lake  St.  Joseph,  mostly S.  30°-l5°  W. 

Also  in  two  localities S.  15°  W.  and  S.  60°  W. 

Albany  River,  between  Lake  St.  Joseph  and  Mamiuiska  Lake,  three  localities. .  S.  20°,  25°,  and  40°  W. 
Maminiska  Lake S.  65°  W. 


638  THE  GLACIAL  LAKE  AGASSIZ. 

Putawonga  Lake S.  75°  W. 

Eabamet  Lake,  two  localities S.  75^^  and  80^  W. 

Inlet  of  Sturgeon  Lake,  Bowlder  Eiver S.70°  W. 

Attawapislikat  River: 

Respectively  3,  13,  22,  and  23  miles  below  the  junction  of  the  two  channels  from  the 

lake  of  the  same  name S.  60°,  42°,  22^,  and  15"  W. 

Lowest  exposure  of  Archeau  rocks S.  to  S.  10°  E. 

On  limestone  about  75  miles  from  the  southern  mouth  of  the  river S.  18°  W. 

On  limestone  9  miles  below  the  last,  two  sets  of  striie,  the  older S.  8°-12°  W. 

And  the  newer S.  60°-70°  E. 

On  limestone  at  the  head  of  Lowasky  Island,  about  44  miles  from  the  southern  mouth 

of  the  river S.  2°  W. 

Southern  channel,  or  Lowasky  River,  4  miles  below  the  last,  the  older  strise S.  35°  W. 

And  newer  striie  varying  in  course  from  the  foregoing  to S.  80°  W. 

Around  Lake  Nipigon  two  sets  of  glacial  strise  are  common,  and  are  often  found  crossing 
each  other  on  the  same  rock  surface.     The  southward  set,  which  is  the  older, 

varies  from S.  18°  E.  to  S.  25°  W. 

And  the  westward  and  newer  set  varies  from S.  50°  W.  to  due  W. 

Along  and  near  Kaministiquia  River S.  to  SW.,  averaging  SSW. 

Dog  Lake,  mean  of  several  localities  (Hector) S.  10°  W. 

Lac  des  Milles  Lacs,  mean  of  several  localities  (Hector) S.  5°  E. 

Sturgeon  Lake,  50  miles  southeast  of  Lonely  Lake,  commonly S.  20°-30°  W. 

But  in  one  locality S.50°  W. 

Minnietakie  Lake  and  vicinity,  west  of  Sturgeon  Lake,  several  localities S.  20°-55°  W. 

Abrams  Chute S.  10°  W. 

Islands  in  the  middle  of  Ahrams  Chute S.  40°  W. 

Lonely  Lake  ( Lac  Seul) : 

Three  localities S.  70°  W.,S.85°  W.,  and  N.  80°  W. 

Three  other  localities,  respectively  10, 13,  and  16  miles  east  of  the  Hudson  Bay  Com- 
pany's post S.60°  W.,  S.  25°  W.,  and  S.  55°  W. 

East  extremity  of  the  lake S.45°  W. 

Root  River,  tributary  to  the  east  end  of  Lonely  Lake,  two  localities S.  50°  and  45°  W. 

English  River,  below  Lonely  Lake,  five  localities S.  30°-60°  W. 

And  one  locality S.80°  W. 

Winnipeg  River,  several  localities  (Bell) S.  20°-55°  W. 

Dr.  A.  C.  Lawson  reports  the  following  many  observations  of  glacial  striiTJ  in  the 
region  about  Ealny  Lake,  on  canoe  routes  north  of  this  lake,  on  the  shores  and 
islands  of  the  lake  itself,  and  on  Eaiuy  Eiver : 

Kishkutena  route,  from  Sabaskong  Bay  of  the  Lake  of  the  Woods  to  the  Northwest  Bay  of 

Rainy  Lake,  seven  localities S.  33°-58°  W. 

Pipestone  Lake  route,  extending  north  from  the  Northwest  Bay  of  Rainy  Lake,  nineteen 

localities S.20°-49°  W. 

Kiarskons  route,  several  miles  east  of  the  last,  six  localities S.  28°-53°  W. 

Manitou  route,  extending  north  from  Manitou  Sound,  the  most  northern  portion  of  Rainy 

Lake,  twelve  localities,  also S.28°-53°  W. 

Little  Canoe  Eiver  route,  a  few  miles  east  of  the  last,  five  localities S.  26°-40°  W. 

Big  Canoe  route,  a  few  miles  farther  east,  five  localities S.  23°^3°  W. 

Redgut  Bay  of  Rainy  Lake,  and  the  Turtle  Eiver  route,  extending  thence  northeastward, 

twenty  localities S.  23°-63°  W. 

Seine  River  route  and  Bad  Vermilion  Lake,  fifteen  localities S.  36°-63°  W. 

Rainy  Lake: 

East  Arm,  from  its  east-southeast  extremity  to  Brills  Narrows,  twenty-four  localities . .  S.  28°-73°  W. 
East  Arm,  from  Brflle  Narrows  and  the  Seine  River  to  the  mouth  of  the  lake,  forty 

localities S.  28°-61°  W. 


COUESES  OF  GLACIAL  STEIiE.  639 

Eainy  Lake — Continued. 

North  Arm,  thirty -seven  localities S.  18°-53°  W. 

Northwest  Bay,  eleven  localities S.  37°-50°  W. 

Eainy  River : 

Island  4  miles  above  the  Manitou  Rapids S.  38°  W. 

One  mile  below  the  Long  .Sault,  and  at  the  first  and  second  rapids  of  Pine  River,  three 

localities,  alike S.  24°  W. 

One  mile  above  the  mouth  of  Rapid  River S.  38^  W. 

Around  the  Lake  of  the  Woods,  observations  in  about  180  localities  by  Dr.  A.  C.  Lawsoc 
and  assistants,  and  in  about  60  localities  reported  by  Dr.  G.  M.  Dawson,  "the  great 

majority,"  i.  e.  82  per  cent,  are S.  350-550  w. 

But  13  per  cent  are S.  100-340  w 

And  5  per  cent  are S.  560-83°  W. 

Only  four  localities  showed  courses  more  westerly  than  S.  65°  W. ;  one  of  these  is  on  the 

southeast  side  of  Big  Island,  where  striae  bearing S.  75°  AV. 

Intersect  others  bearing g,  370  \\r 

On  the  west  side  of  Bigsby  Island,  which,  like  the  preceding,  lies  near  the  middle  of  Sand 
Hill  Lake  (the  southern  and  largest  part  of  the  Lake  of  the  Woods),  double  sets  of 

striio  were  observed  in  two  places,  respectively N.  80°  W.  and  S.  20°  W. 

And N.  83°  W.  and  S.  33°  W. 

And  on  a  joint  projecting  from  the  south  shore  in  the  southwestern  part  of  this  Sand  Hill 

Lake,  striai  bear S.  70°  and  65°  W. 

With  others S.  35°  and  33°  W. ;  also,  S.  10°  E. 

[Probably  the  bearings  S.  10°  E.  to  S.  20°  or  30°  W.  belong  to  the  time  of  the 
maximum  depth  and  area  of  the  ice-sheet;  the  prevailing  southwestern  courses,  to 
later  glaciation ;  and  the  more  westerly  deflections,  to  the  time  of  final  melting 
of  the  ice.] 

Minnesota. 

North  shore  of  Lake  Superior  southwesterly  from  Pigeon  Point,  numerous  localities  (Nor- 
wood and  Whittlese.y) S.  250-45°  W. 

Duluth  (N.  H.  Winchell) ".'.'..".'.....       WSw! 

Otter  Track,  Sucker  (or  Carp),   and  Long  lakes,   in  northeastern   Minnesota,   south   of 

Hunters  Island  (Winchell)  ,5W. 

Vermilion  Lake,  two  places  (Winchell),  about S.  20°  W. 

And  in  another  place  (Winchell) g.  40°  w. 

Vermilion  Lake  (Whittlesey)  S.  15°  W. 

Pike  River,  tributary  to  Vermilion  Lake,  two  places  (Winchell) S.  10°  and  20°  W. 

In  township  59,  range  14,  about  20mile8  south-southeast  of  Vermilion  Lake  (Winchell),  esti- 
mated     S.  30°  W. 

The  following,  to  Knife  Lake,  inclusive,  are  observations  by  Prof.  N.  H.  Winchell, 
noted  in  his  Fifteenth  Annual  Eeport,  Minnesota,  for  1886,  pp.  385,  386: 

Vermilion  Lake: 

Twenty  localities S.  17°-24o  W. 

Three  other  localities S.  28°  W.,  S.  10°  W.,  and  S. 

Birch  Lake 8.12°  W.  and  S.  22  W. 

Section  30,  township  63,  range  8 S.  80  E. 

Section  35,  township  63,  range  9 g.  120  ^v_ 

Section  27,  township  63,  range  10 S.  15°  W. 

Basswood  Lake,  Northeast  Cape S.  1!5°  W. 

Ima  Lake,  north  shore S.  36°  W.  and  S.  23°  W. 

Island  in  Thomas  Lake S.  2.5°  W. 

Section  11,  township  64.  range  7 S.  30°  W. 

ICnife  Lake S.  48°  W. 


640  THE  GLACIAL  LAKE  AGASSIZ. 

The  two  following  are  from  Prof.  N.  H.  Wiuchell,  in  his  Sixteenth  Annual  Eeport, 
for  1887,  p.  114: 

East  end  of  Delta  Lake,  west  of  Ogishke  Muncie  Lake S.  25°  W. 

Island  in  Pseudo-Messcr  Lake S.  40^  W. 

Mr.  Horace  V.  Winchell,  in  the  report  last  cited,  pp.  395-478,  notes  the  following 
glacial  striae,  to  Trout  Lake,  inclusive,  corrected  by  him  for  magnetic  variation : 

Little  Fork  of  Rainy  River,  live  localities S.  10°^2°  W. 

Kaiuy  River,  3*  miles  below  Fort  Frances S  32°  W. 

Rainy  Lake,  nine  localities S.32°-64°\V. 

North  fall  on  outlet  from  Namekan  Lake  to  Rainy  Lake S.  30°  W. 

Bowstring  River  (Big  Fork  of  Rainy  River; : 

Probably  in  to wnshii)  63,  range  26,  intersecting  striae,  mainly S.  10°  W.  and  S.  30"  E. 

A  short  distance  above  the  last,  very  distinct  glaciation S.  60°  E. 

Deer  River,  at  dam  about  a  half  mile  above  its  junction  with  the  Big  Fork,  probably  in  town- 
ship 62,  range  25 S.80°  E.  to  due  E. 

Big  Fork : 

About  3  miles  above  the  mouth  of  Deer  River Due  E. 

In  or  near  section  35.  township  150,  range  25 S.  52°  E. 

[The  southeastward  and  eastward  striation  on  the  Bowstring  River  or  Big  Fork 
belongs  to  the  east  part  of  the  glacial  current  that  moved  to  the  south  and  south- 
east from  the  region  of  Lakes  Winnijieg  and  Manitoba,  carrying  plentiful  bowlders 
and  gravel  of  limestone  from  those  lakes  and  the  lower  part  of  the  Red  River  Valley 
southeast  to  this  stream  and  to  the  mouth  of  Rainy  Lake.] 

Lower  Falls  of  Prairie  River,  section  34,  township  56,  range  25 S. 

Elbow  Lake,  township  64,  range  18,  two  localities S.  26°  W.  and  S.  28°  W. 

Pelican  Lake,  mostly  in  townships  64  and  65,  range  20,  four  localities .S.  24°-36°  W. 

Net  Lake,  in  the  Bois  Fort  Indian  Reservation S.  20°-24°  W. 

Trout  Lake,  north  of  Vermilion  Lake,  two  localities S.  16°  VP^.  and  S.  36°  W. 

In  the  Seventeenth  Annual  Eeport,  Minnesota,  for  1888,  pp.  86-118,  Mr.  H.  V. 
Winchell  gives  additional  notes  of  glaciation  as  follows,  to  DisapiJointment  Lake, 
inclusive : 

Section  32,  township  60,  range  13,  about SSW. 

Summit  of  the  Giant's  Range  at  Hinsdale S.  22°  W. 

Section  35,  township  61,  range  12,  south  of  Birch  Lake,  about S.  12°-30°  W. 

Section  36,  township  62,  range  8,  south  of  Lake  Isabelle S.  24°  W. 

Seel  ion  15,  township  59,  range  6,  southwest  of  Crooked  Lake S.  6°  W. 

Section  10,  township  64,  range  8,  north  of  Ensign  Lake S.  24°  W. 

Section  27,  township  64.  range  8,  northeast  end  of  Disappointment  Lake S.  34°  W. 

Sand  Point  Lake  and  Sturgeon  or  Namekan  Lake  (Whittlesey) SW.  to  S.  55°  W. 

Rainy  Lake  (Whittlesey) S.  40°-60°  W.,  and  WSW. 

Big  Fork  of  Rainy  River,  about  82  miles  from  its  mouth  (Whittlesey) S.  80°  E. 

[This  seems  to  be  near  the  locality  noted  by  H.  V.  Winchell  about  3  miles 
above  the  mouth  of  Deer  River.] 

The  Twenty-second  Annual  Eeport,  Minnesota,  for  1893,  on  pages  35-40,  makes 
extensive  additions  to  the  foregoing  lists  of  glacial  striaj  in  the  northeastern  part  of 
that  State,  including  very  abundant  and  exceptionally  deflected  courses  at  Duluth 
and  elsewhere  about  the  west  end  of  Lake  Superior.  In  this  I'eport  (page  42)  it  is 
suggested  that  some  of  the  courses  noted  on  the  Bowstring  Eiver  or  Big  Fork  may 


COURSES  OF  GLACIAL  STRIDE.  641 

really  have  been  westward,  rather  than  eastward,  due  to  ileflectlon  during  the  late 
stage  of  the  glacial  recession  when  the  expanding  Lake  Agassiz  caused  the  ice  in 
northwestern  Minnesota  to  be  melted  away  earlier  than  on  the  land  area  about  the 
sources  of  the  Big  Fork  and  easterly,  so  that  the  previous  glacial  currents  of  that 
area  might  become  reversed  from  eastward  to  westward  courses. 
The  following  striine  are  iu  central  and  southern  Minnesota : 

Hinckley,  Pino  County : S.  and  S.  5'^  W. 

Watab,  Benton  County S.  15°  W. 

Sauk  Kapids,  Benton  County,  numerous  places S.  45"-55°  W. 

But  in  one  place S.  15°  W. 

Sauk  Center,  Stearns  County,  40  miles  west  of  the  last S.  40°  E. 

Minneapolis,  several  places S.  5°-28°  E. 

One  to  7  miles  southeast  from  Big  Stone  Lake,  numerous  places SE. 

Granite  Falls,  several  places S.  45°-50°  E. 

Beaver  Falls S.  60°  E . 

In  the  valley  of  the  Minnesota  River,  2  miles  below  Birch  Cooley S.  60°  E. 

One  and  a  half  miles  west  of  Fort  Ridgely S.  60°  E. 

Redstone,  near  New  Ulm S.  25°  E. 

Jordan,  at  mill  of  Fobs,  Wells  &.  Co SE. 

Posen,  Yellow  Medicine  County S.  .50°  E. 

Echo,  Yellow  Medicine  County S.  50°-55°  E. 

Township  111,  range  38,  Redwood  County S.  50°-60°  E. 

Stately,  Brown  Coiiuty S.  50°-55°  E. 

Germautown,  Cottonwood  County S.  30°  E.,  S.  50°  E.,  and  70°  E. 

Amboy,  Cottonwood  County,  mostly S.  35°-50°  E. 

But  also  rarely  deflected  to S.  70°  E. 

[In  one  place  all  these  courses  intersect  on  the  same  surface.] 
Deltou,  Cottonwood  County,  numerous  localities,  mostly S.  15°-40°  E. 

Also,  in  one  place,  all  courses  from S.  to  S.  80°  E. 

[These  intersect  on  the  same  surface.] 

Selma,  Cottonwood  County S.  18°-22°  E. 

Amo,  Cottonwood  County S.  30°-32°E. 

Dale,Cottonwood  County S.20O-34°E. 

Adrian-, Watonw.an  County S.  20°-30°  E. 

The  only  glacial  striie  recorded  in  North  Dakota  are  on  outcrops  of  a  bluish-gray 
sandstone,  occupying  the  place  of  the  Fox  Hills  sandstone,  on  the  Willow  Itiver,  in 
the  southwest  quarter  of  section  35,  township  Kil,  range  73,  about  6  miles  south  from 
Dunseith  and  the  southern  base  of  Turtle  Mountain.  Distinct  glacial  furrows  and 
strite,  here  observed  in  eight  or  ten  places,  bear  mostly  due  west,  but  in  two  jjlaces 
S.  85°  W.  and  S.  75°  W.  These  stri;e  belong  to  the  closing  stage  of  glaciation  here, 
being  directed  normally  toward  the  Fergus  Falls  and  Leaf  Hills  moraines  and  the 
glacial  Lake  Souris,  whose  eastern  shore  coincided  nearly  with  this  part  of  the  course 
of  Willow  Eiver.  During  the  maximum  extension  of  the  ice-sheet  its  current  at  this 
locality  doubtless  passed  nearly  due  south. 

Almost  universally  throughout  North  Dakota,  eastern  Montana,  and  a  large  area 
stretching  thence  northwestward  to  the  Athabasca  and  Peace  rivers,  the  bed-rocks 
MON  XXV 41 


642  THE  GLACIAL  LAKE  AGASSIZ. 

are  shales  of  the  Fort  Pierre  and  Laramie  formations,  so  soft  and  easily  eroded 
wherever  exposed  to  weathering  that  glacial  marks  are  not  preserved.  The  sand- 
stone of  Willow  Eiver,  however,  outcrops  also  in  the  same  district  on  Turkey  and  Ox 
creeks,  but  does  not  there  retain  striated  surfaces.  Farther  west,  apparently  this 
stratum  of  sandstone  occurs  in  the  blufl's  of  the  Souris  River,  near  its  most  soutberu 
bend,  and  in  hills  within  the  area  of  the  loop  formed  by  this  river,  where  other  glacial 
strisB  may  probably  be  found. 


APPENDIX  B. 

NOTES  OF  ABORIGINAL  EAETHWORKS  WITHIN  AND  NEAR  THE  AREA 

OF  LAKE  AGASSIZ. 

Archeologists  will  be  interested  iu  the  following  brief  notes  of  the  localities  of 
mounds  in  this  district,  to  which  reference  has  been  made  in  Chapter  XI,  page  612. 

Many  mounds,  probably  not  less  than  fifty  in  all,  varying  from  2  to  15  feet  iu 
height,  are  situated  on  the  bluffs  of  both  sides  of  Lake  Traverse,  Browns  Valley,  and 
Big  Stone  Lake. 

Three  isolated  mounds,  each  about  5  feet  high,  were  noted  on  the  right  bank  of 
the  Red  River,  in  Wilkin  County,  Minn.,  one  being  about  12  miles  east  of  Brecken- 
ridge,  another  about  4  miles  north  of  that  town,  and  a  third  in  McCauleyville. 

Close  south  of  the  Red  River,  near  the  mouth  of  Ottertail  Lake,  is  a  group  of 
sixteen  mounds,  varyiug  from  1  to  10  feet  iu  height;  and  others,  single  or  in  groups, 
are  found  at  many  places  in  Ottertail  County, 

In  Clay  County,  Miun.,  a  small  mound  was  noted  near  Muskoda,  and  another 
near  the  South  Branch  of  the  Wild  Rice  River. 

(More  detailed  statements  concerning  these  and  the  foregoing  localities  are  given 
in  the  Geology  of  Minnesota,  Vol.  I,  p.  631,  and  Vol.  II,  pp.  533, 558-561,  and  671.) 

Mounds  and  artificial  embankments  are  situated  on  and  near  the  beaches  of  Lake 
Agassiz  in  many  jjlaces.  In  the  greater  part  of  these  iustauces  the  earthworks  have 
been  already  described,  or  at  least  mentioned,  iu  this  volume  (pp.  284, 313, 347, 349,  354, 
390, 412, 413,  431).  Among  all  these  localities  the  most  notable  is  close  north  of  the 
Forest  River,  about  6  miles  northwest  of  Inkster  (p.  349).  According  to  a  survey 
of  this  group  of  mounds  by  Mr.  T.  H.  Lewis,  they  number  about  forty,  ranging  from 
li  feet  to  13  feet  in  height,  some  of  them  being  connected  by  low  embankments. 

In  the  south  part  of  Crookston  an  aboriginal  mound  about  6  feet  high  and  100 
feet  iu  diameter  lies  on  the  south  bluff  of  the  Red  Lake  River,  close  east  of  Mr. 
Erskine's  brickyard. 

On  the  prairie,  close  west  of  the  mouth  of  Red  Lake  and  north  of  the  Red  Lake 
River,  is  a  large  mound  about  15  feet  high. 

Beside  the  Roseau  Lake  trail,  between  2  and  4  miles  eastward  from  its  crossing  of 
the  South  Branch  of  Two  Rivers,  five  oblong  mounds  or  embankments,  each  about  3 
feet  high,  are  reported  by  Mr.  Charles  Hallock,  These  are  on  the  crest  of  a  beach 
ridge,  probably  the  Tintah  beach. 

Two  mounds,  respectively  5  and  3  feet  high,  are  situated  about  half  way  between 
Fort  Pembina  and  the  town  of  Pembina,  being  some  three- fourths  of  a  mile  north  of 
the  fort  and  an  eighth  of  a  mile  west  of  the  Red  River, 

643 


644  THE  GLACIAL  LAKE  AGASSIZ. 

In  tbe  vicinity  of  Devils  Lake,  Sweetwater  Lake,  and  Stump  Lake  are  many 
moimds,  mostly  3  to  6  feet  high,  very  rarely  rising  to  10  feet,  occurring  singly,  as  on 
tbe  tops  of  the  hills  near  Fort  Totten,  and  in  groups  of  several,  or  sometimes  forty  or 
more,  as  at  the  southeast  end  of  Devils  Lake.  Other  lone  mounds  and  series  of  mounds 
are  seen  here  and  there  along  the  bluffs  of  the  Sheyenne  and  James  rivers. 

The  largest  mound  known  in  Minnesota  is  45  feet  high,  being  the  central  one  of  a 
group  of  three  (the  two  others  only  8  or  10  feet  high)  on  tbe  south  side  of  the  Eainy 
River,  close  east  of  the  mouth  of  the  Bowstring  Eiver  or  Big  Fork.  This  mound,  par- 
tially excavated  under  the  direction  of  Prof.  George  Bryce,  was  found  to  contain 
many  skeletons,  and  also  skulls  without  other  parts  of  tbe  skeleton,  as  if  they  had 
been  collected  on  a  battlefield.  There  were  also  found  very  interesting  stone  and 
copper  implements,  ornaments  made  from  seashells  and  others  of  fresh-water  shells, 
broken  pottery,  and  a  complete  pottery  cup  having  a  diameter  of  3  inches.  Professor 
Bryce  states  that  twenty-one  mounds  are  discovered  along  the  whole  course  of  tbe 
Kainy  River,  one  (peculiar  in  containing  a  structure  of  charred  logs  some  10  feet 
square  and  6  to  8  feet  high)  being  at  the  mouth  of  Rainy  Lake  and  several  at  the  Long 
Sault.  On  tbe  Red  River,  in  Manitoba,  he  reports  one  mound  as  formerly  existing  at 
Winnipeg,  and  several  still  to  be  seen  near  the  rapids  about  10  miles  below  that  city. 
(Historical  and  Scientific  Society  of  Manitoba,  Transaction  18, 1885.) 

On  the  Souris  River  and  its  tributaries,  the  North  and  South  Antler  creeks,  Pro- 
fessor Bryce  surveyed  twenty-one  mounds  within  an  area  of  i  miles  square,  ranging 
from  4  to  7  feet  in  height.  One  of  these  mounds,  containing  a  single  skeleton,  had 
■with  it  nearly  all  the  types  of  stone  implements,  copper  and  seashell  ornaments,  and 
pottery,  which  had  been  found  in  tbe  large  mound  on  tbe  Rainy  Eiver,  about  325 
miles  distant  to  the  east,  besides  two  pipes  of  red  pipcstone;  but  in  each  case  no  evi- 
dence of  any  intercourse  with  Europeans  was  found.  (Historical  and  Scientific  Society 
of  Manitoba,  Transaction  24, 1886.) 

During  my  survey  of  the  shorelines  of  Lake  Agassiz  in  Manitoba  and  examina- 
tion of  tbe  adjoining  country  on  the  southwest,  I  observed  mounds  in  many  localities, 
of  which  tbe  following  are  the  most  noteworthy: 

In  the  northwestern  edge  of  the  village  of  Arden  tbe  crest  of  tbe  Campbell  beach 
bears  a  round  mound  4  feet  high  and  75  feet  in  diameter,  with  an  embankment  2  feet 
high  and  30  feet  wide  extending  from  it  50  feet  northward.  A  mile  south  of  Arden, 
on  this  broad  beach,  a  few  rods  east  of  its  crest  and  about  1  foot  lower,  is  an  embank- 
ment 20  to  25  feet  wide,  about  200  feet  long  from  north  to  south,  parallel  with  the  beach 
crest,  and  IJ  to  2  feet  high.  Along  its  northei'n  two-thirds  this  earthwork  is  straight, 
but  its  southern  third  curves  somewhat  eastward  and  this  end  sinks  gradually  to  the 
general  surface. 

Tbe  formerly  famous  Cilf  Mountain,  which  was  visited  by  PalUser's  expedition 
and  appeared  prominent  on  most  of  the  early  maps  of  Manitoba,  is  an  aboriginal  mound. 


ABORIGINAL  EARTHWORKS.  (345 

prob.ably  built  over  a  slight  natural  mound  of  the  glacial  drift.  Tbis  earthwork, 
rising  only  about  15  feet  above  the  adjoining  surface,  is  near  the  north  line  of  the 
northeast  quarter  of  section  32,  township  2,  range  7  west.  Its  top  is  about  40  feet  above 
Darlingford  railway  station  and  IfiOD  feet  above  the  sea.  From  it  the  land  descends 
fast  eastward  to  Thornhill  and  Morden,  overlooking  farther  east  the  vast  valley  plain 
of  the  Red  River.  The  earthwork  consists  of  till,  inclosing  frequent  bowlders  up  to  1 
foot  in  diameter,  with  aconsiderableadmixtureof  gravel,  which  was  probably  brought 
from  the  shores  of  a  beautiful  lakelet  a  few  hundred  feet  distant  to  the  north.  The 
diameter  of  the  principal  mound,  which  is  dome-shaped,  is  95  feet,  with  a  height  of 
15  feet.  Thence  an  embankment  about  2  feet  high  extends  10  rods  southwest,  and 
its  farther  portion,  turning  with  a  right  angle,  continues  about  4  rods  to  the  south- 
east. Excavation  in  the  mound  has  brought  to  light  human  bones  and  many  buffalo 
skulls,  often  much  decayed  and  fragmentary.  The  name  Calf  Mountain,  probably  a 
translation  from  an  aboriginal  name,  refers  to  this  united  sepulture  of  the  remains  of 
man  and  the  buffalo. 

Several  round  mounds,  2  to  4  feet  high,  are  situated  on  the  bluffs  of  Mowbray 
and  Snowflake  creeks.  Two  of  these,  near  the  southeast  corner  of  section  0,  township 
1,  range  0  west,  were  found  to  contain  in  each  four  or  five  skeletons. 

On  the  top  of  Star  Mound  (p.  99)  an  artificial  mound,  built  of  till,  with  bowlders 
up  to  a  foot  in  diameter,  has  a  height  of  about  4  feet  and  diameter  of  50  feet,  with 
slight  embankments  extending  beyond  its  circumference  about  20  feet  to  the  north 
and  south.  Similarly,  the  top  of  Pilot  Mound  (p.  99)  has  an  earthwork  about  2  feet 
high  and  50  feet  in  diameter.  The  crests  of  a  few  of  the  Tiger  Hills  are  also  crowned 
with  small  mounds,  some  of  which  have  been  excavated  and  are  found  to  have  been 
built  for  purposes  of  burial. 

On  the  southeast  bluff  of  the  Cypress  River,  close  east  of  the  mouth  of  Tiger 
Creek,  are  three  mounds,  of  which  the  most  northeastern  and  largest  is  0  feet  high. 
These  are  on  land  about  25  feet  above  the  general  level  of  the  surrounding  country 
and  1,200  feet  above  the  sea. 

Resides  the  foregoing,  which  I  have  examined,  my  assistant,  Mr.  Robert  H. 
Young,  noted  a  mound  about  4  feet  high  and  GO  feet  in  diameter  on  the  crest  of  the 
southeastern  eud  of  a  beach  like  esker  iu  the  southeast  quarter  of  section  30,  town- 
ship 12,  range  1  east,  near  the  Grosse  Isle  (p.  187). 

A  very  large  mound,  said  to  be  about  10  feet  high,  is  reported  on  land  of  Mr. 
William  Rhind  beside  the  White  Mud  River,  about  a  mile  west  from  Westbourne. 
On  its  surface,  or  not  far  below  it,  stone  pipes,  pottery,  and  human  skulls  and  other 
bones  have  beeu  found;  but  at  the  time  of  this  information  no  deej)  excavation  had 
been  made. 


INDEX, 


Page. 

Abifctibi,  Lake 205,233 

Ablation 210 

Aboriginal  earthworks 284, 

313,  347,  349,  254,  390,  412,  413,  431,  611,  643-640 

Ada,  Minn 133,169,211,557 

Adama,  F.  D.,  analyses 537 

Adhemar,  J.,  cited 489 

Adirondack  Mountains,  glaciation  of 110, 

203,  260,  203, 263,  505 

Aftonian  stage  of  Glacial  period 280, 554 

Agasaiz,  Alexander,  cited 513 

Agassiz,  J.  Louis  R,.  biographic  notes 5 

on  glacial  atriffi 637 

on  glaciation  of  Patagonia 509, 510 

Agasaiz,  Lake,  named  for  Louis  Agassiz 5 

altitude 14 

area 2,214,216.218,220,479 

area  of  its  drainage  basin 03,  64 

depth Ill,  213,  215,  218,  219,  470,  479 

duration 198,  200,  225,  240,  242 

extension  with  departure  of  the  ice- 
sheet 208.214 

islands 107,  288,  304, 345-  352,  390 

northeastern  boundaries 11,29,62 

northward  uplift  of  basin 147, 

217,  224,  227,  267,  382,  474-483,  485 

outlet  by  the  River  Warren 7, 

15, 19,  222,  224, 250, 478 

outlets  northeastward 215, 

216,226,231,443.479 

stages 210,250,444.474.476 

succeeded  by  Lake  Winnipeg 220,  226 

tabular  list  of  beaches  and  their  alti- 
tudes        476 

volume  of  water  discharged  from 252 

Agricultural  resonrces 2,582-625 

Airy,  G.  B.,  cited 494 

Alaska,  epeirogenic  movements 509 

mostly  unglaciated Ill,  128,  243, 247 

Alexander,  Lake,  Minnesota 159, 163 

Algonkian  formations 65,  70,  90 

Algonquin,  glacial  lake 233 

Alkaline  efflorescence 524,590 

.soila 588.589,590 

waters 524,540,559 

Alluvium 160,201,208, 

253,  205,  392,  317, 334, 354,  378, 380, 438, 583, 590, 597 

Alraasippi,  Manitoba 453 

Alta  Viata,Minn 90 

AUamont  moraine 30, 139, 141 

Altitudea  of  Lake  Agassiz  area 9, 14,  31,43 

Amenia,  N.  Dak.,  artesian  well 569 

Analyses  ol  alkali  etiloreacence 524 


Page. 

Analyses  of  artesian  well  waters 536-540 

river  and  lake  waters 540-544 

Andrews,  E.,  cited 238 

Angus,  Minn 455,459,562 

Antelope  moraine 139, 141 

Antelope  Valley,  North  Dakota 157 

Appaliichian-Laurentide  mountain  belt 14,  104 

Archean  bowlders 120, 

130, 131,  136, 152, 156, 174, 186,  393, 405, 409,  588,  626 

Archean  formations ] 6, 65, 76, 78, 89, 133, 556, 625, 631 

area  in  Minnesota 66, 183,  583 

decomposition  of 89 

Arctic  archipelago 102,112,127,503 

Arden,  Manitoba 371,424,441,580,044 

Ardoch,  N.  Dak 460,574,585 

Areaof  Lake  Agassiz 1,2,14,214,216,220,479 

Arrow  Hills 130,140,175,177,271,400 

Artesian  water  supply 523-581 

sources  of  fresh 520,  576 

sources  of  saline 527-530,  561,  576 

use  for  irrigation 545 

Artesian  wells 2, 13,74-80,523-581 

notes  of  on  the  Lake  Agassiz  area  . . .  548-581 

section.  Browns  Valley,  Minn 89 

Deloraine.  Manitoba 83.  529 

Devila  Lake,  N.  Dak 529 

Gratton,  N.  Dak 74.77 

Humboldt,  Minn 74 

Janie3town,N.  Dak 529 

Morden,  Manitoba 74,81 

Roaenfeld,  Manitoba 74, 78 

Tower  City,  N.  Dak 535 

Arthur,  N.  Dak 417 

Arvilla.  N.  Dak - 165,  403, 418,  436,  573 

Assiuiboine  delta ". 27, 

50, 178, 189,  202,  271,  367,  370-381 ,  424,  548,  587, 591 

Assiuiboine  Elver 42,  45,  50,  58,  98,  271,  380,  631 

analyses  of  water 543 

glacial  stria> 036 

Athabasca,  glacial  lake 64, 205, 233.  274 

ithabasca  River  63.205,331,636,641 

A  thert  on  .Minn 409,  429 

Attawiipishkat  River,  glacial  strije 638 

Attix  Ridge 300 

Attraction  of  the  ice-sheet 227, 

228,  231, 484, 488-491,  498,  515,  522 


Babbitt,  Miss  Franc  E.,  cited 11 

B.lldHill,  N.  Dak 154 

Baldwin,  S.  P.,  cited 243 

B.altic  Sea,  Champlaiii  8ul>sidence  and  reelevation 511 

Barley,  statistics  of  production 620 

647 


648 


INDEX. 


Barnesyille,  Minn 287, 385, 400, 409, 654, 555 

Bars,  a  variety  of  beacli  deposits 348 

Baselevfling  of  tlie  Great  Plains 102 

Batligate,  N.  Dak 463, 469,  570 

Beach  ^idges 3, 

20,  147. 167, 196, 199,  217,  221,  261,  267,  276-473,  506 

eastward  ascent 237, 483-485 

nortll^\'ard  ascent 147, 

218,  230,  234,  267,  382,474-483, 485 

tabular  list,  witli  altitudes 476 

terrace  deposits  of  beach  gravel .  344,  360,  365, 422 

wave  action  in  formation  of 348, 386, 421. 446 

wells  on 548 

Beans  station,  North  Dakota 452,456 

Beautiful  Plain 424,425 

Beavers 302,327 

Becker,  G.F., cited 495 

Bell,Eobert,  cited 68,112,119,128,140,204, 

216,  220,  232,  238,  239,  275,  505,  608,  542,  636,  637 

Nelson  River  described  by 29,67 

observations  of  glacial  strije 633 

on  transportation  of  bowlders 131 

Belle  Plaine,  Minn.,  deep  well 17,225 

Belly  River  formation 82,83 

Belmont,  N.  Dak 166,218,462 

Bolt,  T.,  cited 511 

Beltrami,  J.  C.  cited 52,305 

Beltrami  Island,  of  Lake  Agassiz 29, 178,  304, 388 

Beltrami,  Minn 165,559 

Big  Butte,  North  Dakota 162, 171,  2119,  243 

Big  Coul6e,  North  Dakota 268, 270, 317 

Big  Fork  of  Rainy  River 51, 178,  304,  305, 644 

glacial  stria^. 640, 641 

Big  Grass  Marsh  and  River 134,  425,  464,  467,  587 

Big  Slough,  Manitoba 178, 377 

Big  Slough,  North  Dakota 149 

Big  Stoue  Lake 15, 17, 18,  45, 141, 198,  208,  222,  265, 427,  643 

analysis'Of  water 543,  544 

Birds  Hill,  Manitoba 175, 181, 183-188,  210,  213,  243 

Bismarck.  N.  Dak.,  weather  records 592-600 

Black  Bear  Island,  Lake  Winnipeg 69, 137,035 

Black  Island,  Lake  Winnipeg,  moraine 215,220,472 

Blanchard,  N.  Dak 159,  448,  526, 531,  535 . 

Blanchard  beaches 218,  222,  226,  445-449,  479 

Blanford,  W.  T.,  cited 513,  547 

Blooming  Prairie,  North  Dakota 145 

Blue  Earth  River,  Minnesota 264,264 

Bluraeufeld,  Manitoba 453 

Blumenort,  Manitoba 464, 467 

Bois  Brul6  River 256 

Bois  des  Sioux  River 20,  45,  56,  211,  212,  280,  300,  397, 408 

Bonanza  farms 614 

Bonneville,  Lake 1, 192,  228,  241, 194, 496,  595 

Bottom-lands 20,270,292,342,605 

Boutwell,W.T.,  cited 173 

Bowlder-clay 46,108,119,122,134 

Bowlders 136,198 

absent  from  beaches  and  deltas . .  1 88,201, 290, 381, 627 

abundant  in  front  of  beaches 386,  395 

localities  of,  abundant  and  large 137, 

148,  149. 152. 153. 155, 159,  104, 165, 168, 
171, 174,  186, 198,  287,  289,  304,  341,  343, 
354,  355,  386,  393,  395,  405,  411,  409.  583 

on  Pembina  Moiintaiu 41, 137, 4o4 

transportation  of 109, 115, 130, 191 

worn  by  buffaloes 139 

Bowstring  Lake  and  River 32, 51, 178, 304, 305, 640, 644 


Boyne  River,  Manitoba 66, 97, 99, 

Brainerd,  Minn 

Brandon,  Manitoba 368,  370, 

Brandon  glacial  lake ' 

Br,andou  Hills 130, 140, 175, 176, 271, 

Breckenridge,  Minn 22,  54,  211,  553, 

Brick  making 

Brine  in  wells 75,78,100.537, 

British  Columbia,  epeirogenic  movements 231, 

glaciation 111,119,127, 

British  North  American  Boundary  Commission 6, 

Broken  Bone  Lake,  North  Dakota 162,172,176, 

Browns  Valley 15, 17,  89, 197, 

artesian  wells 

Eryce,  George,  cited 48, 

Buflalo  delta 27, 189, 212, 290- 

Bulfalo  River,  Minnesota 56, 

Buffaloes 139, 

Building  stone 

Burns  Ridge,  Manitoba 

Burnside.  Manitoba 

Burnside  beach 219,226,465- 

Butte  Mashue 

Buxtou,N.  Dak 159,165,448, 


Page. 
371,587 
543,  544 
374,  580 
271,  377 
308,  406 
613,  627 
625,  627 
538,  629 
505,  508 
128,  206 
401,433 
209,  243 
265,  643 
.  89,539 
612,  644 
-292,  410 
446,  631 
582,  601 
625,  626 
..  187 
467 
468,  479 
155, 170 
462,  455 


Calciferous  formations 75,76 

Caledonia,  N.  Dak l.'iO,  160, 211,  218, 460 

Calf  Mountain,  Manitoba 644 

Calgary,  drift  near 121 

Call,  R.  E..  determination  of  fossils 238 

Cambrian  formations 17,  65,  76,  78 

Campbell,  Minn 133,408,552,630 

Campbell  beaches. . .  216,  221,  224,  234,  237,  316,  407-426,  482,  644 

fresh-water  shells  of 237 

Canadian  Geological  .Surrey,  work  on  Lake  Agassiz. . .  8 

Canadian  PaciHc  Railway 49,52,135.187,204, 

205.  364,  309,  379,  424,  433,  442,  458,  404,  469 

Canadian  part  of  Lake  Agassiz  1,213,216 

Cauyouerosion 104.105 

Carberry,  Manitoba 376,  580 

Carman,  Manitoba 133,464.467.580 

Carman,  Minn.,  artesian  wells 640,  544,  547,  660,  630 

Casselton.  N.  Dak 133,  448,  534,  568 

Catskill  Mountains,  glaciation  of 117, 125 

Causes  of  the  Glacial  period 125,604.517 

Cavalier,N.  Dak 457,027 

Cedar  Lake,  Saskatchewan  River 46, 61,  636 

Chains  of  lakes 145,223,265 

Chalmers,  R.,  cited 605 

Chamberlin,  T.  C, cited 4,7,76, 

109, 129, 132, 179, 234, 492, 498,  517,  518,  627 

alternative  interpretations 244-251 

on  glacial  lakes  195, 208 

on  limestone  detritus  in  drift 132 

on  stages  of  the  Glacial  period 110, 

280,  518 

on  terminal  moraines 139 

Champion,  Minn.,  artesian  wells 551 

Ch.amplain,  Lake 127,  203,  231,  232,  255,  262,  264,  605 

Champlain  ejiocli  127,128,233,253,259,263 

marine  beds 505,508 

subsidence 127, 

229,  233,  203,  505,  510,  511,  519,  621 
uplift  from  the  subsidence .  234, 204, 507, 511 


INDEX. 


649 


Page 

Changes  in  the  levels  of  beaches 9, 10, 223, 229, 474-522 

Chaimels  of  prejilacial  or  interglucial  rivers 17, 

100, 145, 17(1,  172,  222,  223,  270,  280,  317,  551 

Chapman,  E.J. ,  cited 260 

Chater,  Manitoba 369,  580 

Chazy  fornaations 69,70,75,70 

Chicago  and  Northwestern  Kailway 38 

Cliioago  outlet  of  Lake  Warren 257,  260 

Chippewa  River,  Minnesota 19 

Churchill  River 44,  63,  68, 128,  215,  231, 237, 275,  637 

glacial  striaj 634,637 

Claypole,  E.  "W.,  cited 119,261,494 

Clearwater  River,  Manitoba 58,  209 

Clearwater  River,  Minnesota 64,  303,582,631,032 

Clifford.N.  Dalj 324,389,403 

Climatic  changes 171 

conditions 592-601 

Cochrane,  A.  S.,  glacial  striffi....' 635,  636 

Colemans  Valley,  N.  Dakota 146 

Colfax,  N.  Dak 434, 566 

Colorado  Canyon 104, 105 

Colorado  formation 82 

Colvin.V.,  cited ■-..       116 

Contoocook  River,  New  Hampshire 202 

Contraction  of  the  earth 518 

Conway,  N.  Dak 419,437,575 

Cooperstown,  N.  Dak 151,154,243 

Cope,  E,  D.,  cited 83 

Cordilleran mountain  belt. ...  14, 101, 119, 122,  242,  513,  514,  547 

outflow  of  ice-sheet 119 

Corn,  statistics  of  production 620 

Coste,  Eugene,  cited 625 

Coteaudes  Prairies 10,35,36,86,91,140,149,151,308 

Head  of  the 39, 

111,  139, 143, 148, 150,  208,  266 

Coteau  du  Missouri 10,  35, 106, 137, 140, 206,  267 

Cottonwood  River,  Minnesota 86 

Coutchiching  series 07 

Crazy  Mountains,  Montana 103 

Cretaceous  formations 17, 

38,  40,  41,  44,  00,66,74,  81-107,  137.  138.  151,  154, 
162,169, 197,  198,  304,  306,  317,  340,  341,  349,  3,55,393, 
422,  528,  548,  550,   553,  567,  572,  580,  589,  626,  629 

former  eastward  e.xtent 87, 100, 101, 198 

Larjxmie  brackish  and  fresh  water  series . .  84, 106 

marine  series  of  Manitoba 83 

the  South  Saskatchewan . .        82 

the  Upper  Mis.souri 81 

sources  of  deposits lOl 

CroU,  James,  cited 489, 517 

Crookston,  Minn 53, 

133,  447,  454, 459,  526,  560,  613,  627,  628,  032,  643 

Crosby,  W.  O.,  cited 132,494,513,517 

Crow  Hills,  North  Dakota 157, 169 

Crow  Wing  River,  Minnesota 163 

Crust  deformation  by  the  ice-sheet 497,  500, 517, 520 

Culver,  G.  E.,  cited 120,530 

Cummings,  N.  Dak 159,448,452,455,631 

Cushing,  tr.  P.,  cited 243 

Cycles  of  rainfall 595 

Cypress  Hills,  Assinibola 85,111,117,118,205 

Cypress  River,  Manitoba 58, 98,  368,  371, 376,  580, 645 

D. 

Dairying 621,  624 

Dakota,  glacial  lake 148, 149,  l.'io,  254, 266 


Page. 

Dakota  Indians 52, 158, 171,  309,  331,  360,  397, 460,  010,  611 

Dakota  lobe  of  icosheet 130,  208,  212.  260,  268,  035 

Dakota  sandstone- . .  74,  81,  82,  84, 86,  87,  89,  96, 100, 567, 568,  571 

origin  of  name 531 

source  of  saline  waters 527-536, 

561,  562,  569,  572,  573 

Dall,  W.  H.,  cited 509 

Dalles  of  AVinuipeg  River 51 

Dairy mple  farm 614 

Dana,  J.  D.,  cited. . ;  114, 116, 127, 128,  263,  503,  505,  517,  518,  605 

Darwin,  C,  cited 509,510,513 

Darwin  G.  H.,  referred  to 493 

Daupiiin,  Lake 47,48,61,442,449 

Davenport,  N.  Dak 448, 567 

Davenport  beach  ridge,  Ontario 261 

I   David.son,  G.,  cited 504 

I  Davis,  E.  C,  leveling 400,412,432 

I  Davis,  W.M., cited 103,263 

Dawson,  George  M.,  cited •. 6,  49, 71,  loo, 

110,  111,  112, 118, 119, 120, 121, 183, 196,  198,  205,  207, 
238,  269,  274,  401,  504,  505, 506,  607,  509,  524,  595, 005 

Dawson,  George  M.,  Cretaceous  series 82,83,97 

early  oliscrvations  of  Lake  Agassiz         6 

glacial  stri;e 039 

Peace  River  silts 64 

Pembina  Mountain  escarpment..        41 

rocks  of  Assiniboia 85 

rocks  of  Manitoba .   72 

section  of  Roscnield  well 79,  80 

Daw.son,  J.  W.,  cited 83,501,505,508 

Dawson.  S.  J.,  leveling 50 

Dawson  Bay,  Lake  "Winnipego-sis 48,  73.  74 

DeGeer,  G.,  cited 263,505,511 

DeVillo,  N.Dak 414 

Dead  Horse  Creek,  Manitoba 364 

Dead  Lakes,  Manitoba 464 

Decomposition  of  gneiss  and  granite 89, 107, 132 

Deloraine,  Manitoba,  deep  well 83,629,534 

Deltas 27, 

199,  200,  208,  211,  215,  242,  246,  253,  290,  298, 
315,  333,  357,  367,  370,  390,  402,  438,  584,  590 

contemporaneous  with  tlie  Herman  beach 291, 

298,  316, 334, 362,  380 

proportion  of  modified  drift 189,  291 

wells  (m 359,548,549 

Denudation  of  the  Great  Plains 102 

Departure  of  the  ice-sheet 120, 521 

Desor,  E.,  glacial  stria^ 637 

Detroit,  Minn 45 

Devils  Heart  Hill 156,157 

Devils  Lake  . .  10, 40, 130, 151, 162, 169, 170, 175,  209,  243,  268,  534 

aboriginal  mounds 644 

artesian  well 96, 100, 528, 539, 546, 547 

Huctu.ations  of  level 695. 597 

Devonian  formations 44,  72, 74, 79, 80, 588 

Diller,J.  S.,cited 103,513 

Dodge,  J.  A.,  analyses 524,536 

Dog  Head,  Lake  Winnipeg 47,09 

Dominion  City,  Manitoba 133,  466,  578 

Donaldson,  Minn.,  flowing  well 564 

Douglas,  Manitoba 369,  371 

Dovre  moraine 146, 147-158, 208,  210,  243,  343,  265,  311,  397 

Downer,  Minn 430 

Drainage  in  Red  River  Valley 428,  459,  58,5,  .586 

Dresbach  formation 74,78 

Drift 108, 132, 134,  .534 

englacial 136, 101, 243, 249, 291, 298, 336, 341, 363 


650 


INDEX. 


Page. 

Drift,  modified 127, 143, 155, 179-190,  210,  CG5 

tliicliiiess  of 16, 133, 136, 137, 151, 171 

Driftless  area  of  Wiseonsiu —       l-il 

Drouglits 545,584,594 

Dry^alslii,  E.  von,  referred  to 248 

Ducli  Mountain 1,35, 

42, 45,  61,  83,  99, 105, 179, 
198,  406,  426, 442, 477, 589 

nortliward  ascent  of  beaclies 235 

Dulutli,  Minn.,  glacial  stria? 639,  640 

weatlier  records 592-600 

Bulnth  and  Manitoba  Railroad 432, 445.  447, 452, 462 

Dulutli  and  Winnipeg  Hailroad 49, 304 

Dumont,  Minn 383 

Dunes  on  deltas 28,  200.  298,  299,  309,  312,  315,  375, 376,  591 

Souris  River 158 

Duration  of  Lake  Agassiz 200, 210,  225, 240 

the  Postglacial  period 238,  516 

Dutton,  C.  E.,  cited 104,494 

Dwight,  N.  Dali.,  artesian  wells 566 


E. 

East  Selkirk,  Manitoba 70,72,135,626 

Eckelson,  N.Dak 144 

Eckelson,  Lake  144,205 

Economic  resources 2,  582,  625-631 

Eden,  Manitoba 395 

Edinburg,  N.  Dak 167,392 

Edwards,  ]?.,  analysis 542 

Eldridge,  G.  H.,  referred  to 82 

Elevations  from  railway  profiles 8,  38,  39,  40,  49,  52 

Elk  Tall  ey,  North  Dakota 165, 107,  335,  337-353,  437 

Elk  Valley  delta 27, 167, 189,  212,  333-336,  390,  403,  418 

Elk  Valley  farm 614 

Elliott,  C.  G.,  on  dr.iin.age 585 

Elm  Creek,  Manitoba 467,587 

Elm  Grove,  North  Dakota 338 

Elm  Eiver,  Xorth  Dakota 45,  56, 417 

Ely.sian  moraine 141,147,152,208 

Embarras  River,  Minnesota 32, 177 

Emerado,  N.  Dak 456,573 

Enierado  beaches 217, 218, 222,  226, 227, 454-458, 479, 482 

Emer.son,  B.  K.,  cited 238 

Emerson,  Manitoba 135. 213, 578 

Englacial  drift 136, 191, 243, 249, 291, 298, 336, 341, 363 

English  River 62,638 

Epeirogenic  movemen  ts 3, 102, 104. 105. 118, 125, 126, 

127, 199,  216,  224,  227-237.  245.  259, 
329.  382,  386.  407,  427,  474-522,  596 

dependent  on  glaciation 492-501, 

509.  520 
independent  of  glaciation  512-515, 520 
term  proposed  by  G.  K.  Gil- 
bert  '. 103 

wavelike  advance  on  area  of 

Lake  Agassiz 481, 486, 522 

Erie,  N.  Dak 323,324 

Erosion  by  lake  waves  - .  26, 198. 199.  242.  277,  316,  323,  344,  355, 
380,  389,  392,  394,  407,  410,  4U,  415,  420,  422.  434 

by  the  River  Warren 150,  222,  250 

glacial 89. 1 32,  588 

postglacial 127.221.226 

preglacial 17, 35,  38, 

40.  44.  59,  89. 100,  102,  104, 107, 145,  198.  222,  501-504 

Escarpments  of  lake  erosion 27.  277,  283, 

316,323,  389,  392,  394,  410,  411,418,420,425,428 


Page. 

Escarpments  of  preglacial  erosion 35,  40, 105, 439 

Eskers 175,179,183-188,201,210,243,645 

Euclid,  Minn 169,459,561 

Europe,  epeirogenic  movements 229 

glacial  lakes 5 

ice-sheet 125 

postglacial  period 239 

Everest,  N.  Dak 448,567 


Fairford  River,  Manitoba 61 

Fargo,  N.  Dak 22,  55, 133,  211,  218,  556,  567,  613 

Fargo  and  Southwestern  Railroad 39, 3]  5, 389, 402 

Farm  work  in  the  Red  Eiver  Valley 584,  598,  613,  614,  615 

Farmhouses  on  beach  ridges 3,276 

Faults,  absent  in  uplift  of  the  Lake  Agassiz  area 483 

Fauna,  molluscan,  of  Lake  Agassiz 4,  237 

Fergus  Falls.  Minn 33,45,54, 158.632 

analysis  of  water  of  Red  River 540.  544 

Fergus  Falls  moraine. . .  146, 158-162, 163,  208,  211,  242,  329,  641 

First  Pembina  Mountain 27,  41,  57,  96,  300,  392, 420, 438 

Fish  Traj)  Lake,  Minnesota 163 

Fisher,  Minn.,  wells 561 

Fisher,  O.,  cited 494 

Fishing  Banks,  from  Newfoundland  to  Cape  Cod. . .  112, 503 

Fishing  Lakes,  Qu'  Appelle  River 197, 273 

Fjords 102,501,507,509,510 

submarine 263,  502,503 

Flaxseed,  statistics  of  production 623 

Fleming,  S.,  cited 261 

Floiid  stages  of  Lake  Agassiz 252 

Floods  of  Assiniboine  River 58,380,542 

Lake  Manitoba 58,  380 

Red  Eiver 55, 166,  254,  438,  542,  598 

Flora  of  the  Red  River  basin 582,601-610 

Flowers  of  prairies  and  beach  ridges  . . .  284.  307,  425.  609,  610 

Flowing  wells 523-581 

Fluctuations  of  lake  levels 250,  252,  277 

Fluvial  deposi  ts 166,  201,  208,  253 

Forest  bed,  interglacial 554, 555 

Forest,  causes  of  limitation 604 

Forest  part  of  Lake  Agassiz  area 1, 29, 

30, 44,  279,  387,  413,  583,  586 

Forest  River,  N.  Dak 56,  340, 348, 437, 535, 585,  587,  631 

Forest  trees,  species  of 45,  299,  304,  343,  389,  413,  602,  603 

Fort  Abercrombie,  N.  Dak 55,  429 

Fort  Benton  formation 81, 

82,  84, 86,  92,  96, 106,  550,  553,  556,  565,  507,  629 

Fort  Frances,  Ontario 50,632,640 

Fort  Pierre  formation 81,82,83,86.90,91.94.96,98, 

153, 170, 173, 189,  269,  270,  333,  394,  405,  439,  581,  642 

Fort  Totten,  N.  Dak 156, 157, 169.  644 

Fossils,  Cretaceous 82.  86, 92, 95 

Baculites  ovatus 91,92,94,96 

Belemnitella  manitobensis 98 

Inoceramus  problematicus 91,  99 

sagensis 92.  94,  95 

Lamna  mudgei 94 

Nucula  cancellata 91 

Ostrea  congesta 97,  98,  99 

Otodus  appendiculatus 87 

Pachyrhizodus  latimentum 94 

Placenticeras  placenta 91 

Scaphites  nicolletii 91, 95 

nodosus ^ 94  ^ 

Fossils.  Ple:stocene  and  Recent 202, 207, 

231,  237, 253,  259,  262,  264,  322,  505-508,  510, 554,  555 


INDEX. 


651 


Fossils,  Pleistocene  and  Kecent: 

Gyrawlus  par\nis 238 

Litorina  litorea 512 

Spbaerium  striatinum 237 

sulcatum 238 

Unio  cllipsi  s 237 

Unio  luteolus 237 

Toldia  (Leda)  arctica 506 

Fossils,  Silurian: 

Pycnostylua  guelphensis 73 

Fox  Hills  formation 81, 82,  90,  97, 173,  041 

Franklin,  John,  referred  to 275 

Frencbmans  Bluff,  Minnesota 159,  296 

Frog  Portage,  Churchill  Eiver 275, 637 

Frosts,  earliest  and  latest 599,620 

Fruits 590,624 

G. 

Gahb,  W.M.,  cited 513 

Galena  limestone 70,  71,  74,  76,  77,  79,  80 

Galesburg,  N.Dak 324,326 

Gardar,  N.  DakT 352,364,392,419 

Gary  moraine 37, 139, 141 

Gas,  natural 563,571,631 

in  well  water 553, 569 

Geikie,  A.,  referred  to 493, 517 

Geikie,  James,  cited 109,125,510,517,518 

Geologic  formations  underlying  the  drift 65 

Giants  Kauge,  Minnesota ^. ..  30,  31,  32, 177 

Gilbert,  G.  K.,  cited 4, 199,  227,  232, 238, 261, 492, 595,  598 

defining  epeirogeny 103 

on  Lake  Bonneville 192, 194, 494,  496 

Lake  Iroquois 257-262 

rhythmic  stream  erosion 224 

GilflUan,  J.  A.,  cited 52,54,163,173,177,535 

Glacial  currents 109, 126, 129, 167, 182.  243,  247,  262,  351,  640 

Glacial  erosion 89, 132, 588 

Glacial  lakes,  defined 194 

evidences  of 195-202 

in  Europe 5 

Sargent  County,  N.  Dak. . . .  148, 149, 152,  266 

influence  on  deposition  of  drift 190,  242 

of  the  Peace  and  Athabasca  basins 63, 

206,  255,  274 

of  the  St.  Lawrence  basin 126, 202, 255-264 

Glacial  period 108,128,255,512,515,517 

causes  of 125,504,517 

stages  of 110,280,554 

Glacial  rivers 141', 

161, 167, 179, 182, 196,  205,  234,  292,  298,  336,  362,  418 

Glacial  stria! 108,115,129,130,132,182,239 

deflected 633,635,637,639,641 

table  of 129,633-642 

Glacial  watercourses 164,165 

Glaciers  contemporaneous  with  Lake  Bonneville ■  194 

Gladstone,  Manitoba 234,  236, 371, 464,  580 

Gladstone  beaches 218, 237, 462-465, 479, 483 

fresh- water  shells  of 237 

Glasston,  N.Dak.,  wells 575 

Glen  Koy ,  parallel  roads  of 5 

Glenboro,  Manitoba 373.580 

Glenora  prairie,  Manitoba 269 

Glyndon,  Minn 253,446,555 

Gneiss  bowlders 138 

Gold  mining 625 

Golden  Lake,  N.  Dak 168,  330 

Golden  Valley,  North  Dakota  ...  165, 167, 336, 342-344, 349, 437 


Page. 

Goodchild,  J.  G .,  referred  to 511 

Goose  Eapids,  Red  Elver 55, 159, 165, 166 

Goose  Paver,  North  Dakota 55,  56,93,  327,  332,  336,  631 

Graceville,  Minn 281 

Grafton,  N.  Dak.,  artesian  wells 74, 77, 133, 536, 575, 627 

beaches  near 463 

Grand  Forks,  N.  Dak 23, 133,  219, 573, 627,  628 

junction  of  rivers 52 

Grand  Marais,  Minn 53, 463 

Grandin,  N.  Dak 133,  451,  455,  525,  526,  569 

Grandin  Farming  Company 614 

Granite 66,  67,  75,  77, 89, 107, 157,  353,  359,  393, 469 

Grant,  U.S.,  cited 625 

Grasses 601, 606-609, 621 

Gravitation  toward  the  ice-slieet 227, 

231,  488-491,  498,  515,  522 

Gray, . J.  T.,  cited 556 

Great  Basin,  Pleistocene  lakes 192,  240,  242,  598 

Great  Bear  Hills 44 

Great  Northern  Railway 40, 148, 172,  267,  282,  286,  322, 

324,  333,  346,  351,  387,  390,  397, 412,  418,  432,  450, 613 

Great  Salt  Lake 193 

Greely,  A.  W.,cited 506,512 

Green  Mountains,  glaciation  of 115,  202 

Green  Ridge,  Manitoba 466 

Greene,  N .  Dak 450 

Greenland  ice-sheet 12, 123, 129, 195,  242,  506 

its  motion  discussed  by  T.  C.  Cham- 

berlin 248 

Greenland,  oscillations  of  level 512 

Greenleaf  J.  L.,  cited 632 

Gretna,  Manitoba,  wells 581 

Griftiths  Hill,  Manitoba 185 

Grindstone  Point,  Lake  "Winnipeg 69 

Grinnell  Land,  Champlain  marine  submergence 506,  512 

Griswold,  Manitoba 376,377 

Grosse  Isle,  Manitoba 187,  645 

Gro\-es  in  prairie  region 277,  336,  338,  342,  350 

Guelph  formation 73,  80 

Gulf  Stream,  probable  changes  in  Glacial  period 513 

Gypaum 94 


Hague,  N,  Dak 571,  614 

Hall,  C.  W.,  cited 530,  547,  556 

Hall,  James,  referred  to 497 

Hallock,  C.,  cited 401,433,630,043 

Hamilton,  N.  Dak 463,  468,  575 

Hamlin,  C.E.,  cited 113 

Hand  Hills 85, 117, 118 

Hansen,  A.H.,  cited 5 

Harrison,  J.  B.,  cited 513 

Hatchet  Lake 231,  232,  636 

Hatton,  N.Dak 334,390,572 

Havard.V.,  cited 608 

Hay,  statistics  of  production 621 

Hayden,  F.  V.,  cited 81 

Hayes  River 67,  226, 635 

Heart  Mound 96 

Hector,  J.,  glacial  stria! C38 

Heerman,  E.  E.,  on  fluctuations  of  Devils  Lake 595 

Helgeseu,  H.  T.,  v.aluation  of  horses  and  cattle 624 

Helland,  A.,  cited 243,  248 

Herman,  Minn 68, 133,  282 

Herman  beaches 7, 164,  209, 210, 213,  214, 

216,  221, 234,  335,  243,  250,  276-381, 407,  475, 484,  498 


652 


INDEX. 


Page. 

Heracliel,  J.,  referred  to 497 

Higliwood  Mouiitaina,  Montana 103 

Hilyard,  E.W..  cited 515 

Hillslioro,  N.  Dak 211,451,455,571,031 

Hillsborci  Ijeacll 21 7,  218,  222,  226, 446,  447,  440-454.  479 

Himalaya  Mountains 195,  513,514 

Hind,  H.  Y.,  cited...  48,59,00,62,100,198,221,272,357,473,629 

early  observations  ol'  Lake  Agassiz 6 

on  Tiger  Hills 42 

rocks  of  Lake  Winnipeg 69 

Hinde,G.J.,  cited 261 

Hitchcock,  C.H.,  cited... 113,114,118.505,508 

on  absence  of  Pliocene  formations 

northward 504 

Hitchcock,  E.,  limits  of  drift  on  "White  Mountains 113 

Hobart,  N.  Dak 144,154 

Hotlman,  G.  C,  analysis 537 

HolcomI).  S.,  li<;Tiite 630 

Holland,  Manitoba,  wells 580 

Homestead  laws 613 

Hook  beach  deposits 318,428 

Hope,  N.  Dak 161 

Hopkins,  W.,  reibrred  to 493 

Hubbard,  B.,  cited 595 

Hudson  Bay,  epeirogenic  movements.  3,102,230,237,507,508 

glacial  lakes  of  basin 203,  233 

glacial  stria- 234,  033,  637 

thickness  of  ice  over 119,215 

Hudson-Cbaniplain,  glacial  lake 202,  254,  262,  264 

Hudson  River 203,232,262,264 

submerged  cliannel 263,  503 

Hudson  River  formation 70.  79 

Hudson  Slrait 112,  633 

Hull,  Edward,  cited 490 

Humboldt,  Minn.,  artesian  well 74,  530,  537,  545,  565,  629 

Hungerford.  E.,  cited 115 

Hunter,  N,  Dak 435 

Hutton.F.'W,,  cited 517 


Ice-sheet,  area  and  thickness 112, 117, 118, 

attraction  cbiinging  water  levels 

488-491,498, 

barrier  of  Lake  Agassiz 

110,  113, 126,  129,  140, 192,195,  230, 

boundaries 

crust  deformation  by 497, 500,  510, 

currents  of 109,120, 

lobes  of 129,130, 

167, 171, 177,  182, 190,  208, 210,  243, 

of  Greenland 12, 123, 129, 195,  242, 

of  northern  Europe 510, 

■  of  Patagonia 

recession  of 126,130,160, 

201,  203,  209,  214,  210,  229,  240,  247, 

remnants,  latest 128, 

Iceberg  drift 112,1.10,191,201, 

Illinois  River 198, 

Immigration 

India,  irrigation 

Indian  agriculture 

Indian  corn,  statistics 

Indian  mounds 

313, 347,  349,  354,  390,  412, 413, 431,  611, 

Inkster,  N.  D.ak 348,391,418, 

Interglacial  formations 100,  261, 


505,  515 
228,  231, 
515,522 
3,5,15, 

,  378,  490 
..  110 
520,  521 
, 167, 247 
142, 160, 
, 292, 329 
248,  506 
511,  515 
..  509 
191, 195, 
,  521,  590 
233,  240 
248.  250 
203,  256 
591,  612 
..  547 
610,  Olu 
.  020 
.  284, 
643-646 
437,643 

506,  554 


Pago. 

Interglacial  stream  channels 145,  222,  223,  270,  280,  554 

International  boundary 401 

Iowa,  eastward  extent  of  Cretaceous  formations 87 

lowan  stage  of  Glacial  period 110. 141. 280, 554 

Iroquois,  glacial  lake 203,  233,  254,  257-262 

Iroquois  beach 258 

Irrigation  b.y  artesian  water 545-547 

Irving,  R.  D.,  referred  to 76 

Islands  of  Lake  Agassiz 167,288,304,345-3.52,396 

Lslea  la  Cro.sse  Lake 68,275,637 

Isostasy ; 494,497.501,512 

Itasca,  Lake 10,  32, 33, 173, 181, 210, 243 

Itasca  moraine 32, 140, 173-177,  209,  212,  242 

Ives,  Minn 432 


James  Bay 

131, 140,  205, 215,  217, 231,  233,  237,  254,  505, 

glacial  lake -..■ 

terminal  moraine  in 

James  River,  North  Dakota 134, 137. 149, 151, 

James  River  Valley,  artesian  wells 100,208, 

glacial  lake 148,150, 

Jamestown,  N.  Dak.,  artesian  well . . .  529.  531. 538,  544 

Jamieson,  T.  F., cited 5,125,494 

Jordan  sandstone 1 

Jukes-Browne,  A.  J .,  cited 


.  119, 

500,  037 
233 
140,215 
197,  206 
528-536 
254,  266 
546,  547 
497,510 
7,  74,  78 
.   513 


K. 

Karnes 157,160,163,179,303 

Kausan  stage  of  Glacial  period 110, 141,  280,  554 

Katahdin,  Mount,  glaciation  of 113, 115, 124 

Keating,  W.  H.,  cited 17,48,50,52,57 

early  observations  of  Lake  Agassiz. . .         6 

on  Winnipeg  River 51 

Keewatin,  Canada 29 

Keewatin  formations 66, 07, 472 

Kelso,  N.  D.ak 451.455,570 

Kemnay,  Manitoba 373,375,378 

Kendall,  P.  F.,  referred  to 511 

Kenogami  L.ike 204,  637 

Kettle  Hill,  beaches 217,  218,  445,  454,  458,  464, 477 

Kettle-holes 174 

Keystone,  Minn.,  artesian  wells 502 

Keystone  farm 614 

Kiester  moraine 141, 152, 208 

King,  Clarence,  cited 82,493 

Koochiching,  Minn 50,  632 

Kootanie  basin,  glacial  lake 208 

Kronsfeld,  Manitoba 448 

Kronsthal,  Manitoba 464 


Labrador,  Champlain  marine  submergence 505 

Lac  du  Bonnet.  Winnipeg  River 52,137 

Lac  qui  Parle .,.  18,19,198 

Lac  Seu'i  ( Lonely  Lake) 52 

Lacustrine  silts 160,  201,  242,  256.  310,  362,  380,  438,  583,  590 

Lafayetti'  period,  erosion 107 

Lahontan,  Lake 1,192,241 

Lake  of  the  Woods 29,  49,  51, 

67, 137. 181, 198,  210,  304,  388.  402,  586 

area,  elevation,  and  depth 49 

glacial  striie 639 

Lake  Superior  lobe  of  the  ice-sheet 142 

Lakes,  fluctuations  of  level 594-598 


INDEX. 


653 


Page. 

Lakes,  in  niorainic  belts 34,110,145,161,103,168,174 

in  A'alle,\'a  of  glacial  rivers 197 

of  Lake  Agaasiz  area 46 

of  preglaeial  or  interglacial  watercourses .  145, 223, 265 

Lamplugb,  G.  W.,  cited 506 

Land,  laws  for  acquiring,  from  United  States 613 

Laugdou,  N.  Dak 151, 175, 001 

Langs  Valley 8,  57, 176, 197,  269,  271,  363,  377,  581 

Laramie  formation 84,106, 173,268,642 

Lariinore,  N.  Dak 23, 165,  212,  333,  345,  352,  436,  574 

La  Salle  River,  Manitoba 56 

Last  Mountain  Laki',  Aasiniboia 60, 197,  272 

Laurcntian  drift  bowlder 120, 121 

Laurentian  formations 66,  67, 75,  239 

L.aurenti.an  lakes 102,126,180,196,198,203,255,260,594 

cycles  of  rise  and  fall 278,  594,  598 

Laurentide  highlands 1 14, 119, 120, 141 ,  202, 260 

outflow  of  ice-sheet 119 

Lawndale,  Minn 286 

Lawson,  A.  C,  cited 49, 183, 257, 625 

observations  of  glacial  striEB 638, 639 

on  rocks  of  Lake  of  the  Woods  and 

Rainy  Lake 67 

Leaf  Hills,  Minnesota 30, 33, 139, 158, 163, 181,  243 

Leaf  Hills  moraine.  146, 158, 163-173, 208,  212, 242, 298,  350,  641 

LeCoute,  Joseph,  cited 104,493,503,504,513 

Leda  clays 508 

Leech  Lake,  Minnesota 33, 173 

Leonard,  N.  Dak 316,  389,  402,  415,  434,  567 

Lesquereus,  L.,  cited 87, 605 

Leveling,  altitudes  of  beaches 9, 226,  279, 407 

in  vicinity  of  Devils  and  Stump  lakes .. .      597 

Leverett,  Frank,  referred  to 4 

moraines  traced  by 140 

Lewis,  H.  C,  referred  to 511 

Lewis,  T.  H.,  surveys  of  Indian  mounds 643 

Lieberg,  John  B..  cited 608 

Lightnings  Neat 309,  388 

Lignite 82,  85,  86,  88, 89,  92, 100,  361,  558,  568,  029 

Lime-burning 71,625,026 

Limestone  drift  bowlders.  137, 155  157, 170, 174, 183,  5S8,  626,  640 

Limestone  gravel 286,313,  319,  320,  322,  353, 

359,  361,  364,  392,  394,  416,  425,  459,  466,  588,  591,  640 

Limits  of  plantlspecies  in  the  Red  River  basin 601-610 

Lindenkohl,  A.,  cited 263, 503 

Lisbon,  N.  Dak 148 

Little  Falls,  Minnesota 147, 159 

Little  Fork  of  Eainy  River 51,100,640 

Little  Goose  River,  North  Dakota 332 

Little  Pembina  River 93,358 

Little  Saskatchewan  River 47,48,61 

Little  Stony  Mountain,  Manitoba 71, 471,  626,  636  i 

Lobes  of  the  ice-sheet 129, 142, 

160, 167, 171, 177, 182, 190,208,  210,  243,  292,  320,  418 

Lockhart,  Minn 296,  558 

Lockhart  farm 614, 630 

artesian  wells 558,  630 

Loess 180,515 

Logan,  W.  E.,  cited 239 

Lonely  Lake  (Lac  Seul) 52,638 

Long,  Stephen  H.,  cited 50 

expedition  in  1823 6, 48,  .50, 52, 57 

Long  Lake,  Assiniboia 60,197,272 

Long  Lake,  Manitoba 50 

Long  Sault,  Rainy  River 50,  644 

Lost  River,  Minnesota 164,  303 

Low,  A.  P.,  cited 140,635 


Page. 
Lowdons  Ridge 441 

Lower  Fort  Garry,  Manitoba 55,  71,  72 

Lower  Magucsian  formation 17,  74,  75,  76,  78,  80 

Lower  Silurian  Ibrmations 17,68,74,75,80,548 

Lundy,  glacial  lake 233 

Lyell,  Charles,  cited 260,517 

M. 

McCanna,  N.  Dak 165,167,213,334,346 

McCauley  ville,  Minn 55,  253,  429,  554,  643 

MoCauley ville  beaches 216, 221,  224,  234, 316, 427-442, 482 

McConnell,  R.  G.,  cited Ill,  117, 122, 196 

McGee,  W  J,  cited 179,  494 

McGregor,  Manitoba 381,  449 

Mackenzie  River 03,  81, 119, 122,  231  255,  275 

Mackintosh,  D.,  cited 239 

Macoun,  John,  cited 239,  275,  604,  609 

Madison  sandstone 78 

Maig.iard,  C.,  referred  to 123 

Maize,  statistics  of  production 621 

Malaspina  ice-sheet 128 

Mammoth  bones  under  the  Herman  beach 322 

Manitoba,  Lake 1, 3, 34, 43, 45, 48, 61, 72,  213, 241 

area  and  elevation 48 

flood  stages 58, 380 

glacial  strijB 636 

origin  of  name 48 

Manitoba,  great  lakes  of 216,220,230,241,586 

order  of  sections  in  townships 11,12 

work  on  Lake  Agassiz 8,9,228 

Manitoba  and  Northwestern  Railway 370, 

394,  424,  441,  445,  449,  458,  467 

Manitoba  escarpment 35, 40, 105, 214, 215, 439 

Manitou  Rapids,  Eainy  River 60,  639 

Manston,  Minn 399, 409 

Manvel,  N.  Dak 466,574 

Maple  Lake,  Minn 23,  47, 104, 105,  209,  221,  299-302,  352 

Maple  Kidge 450 

Maple  River,  North  Dakota 57, 101,  317,  415,  450 

Maps  of  shore-lines 270,279,  410.431 

Marine  submergence  during  the  Champlain  epoch 127, 

229,  264,  505 

Marshes 283,  286,  287,  321,  385.  397,  459,  584-587 

Marsh  River,  Minn 53,  56.  585 

Maryland,  Manitoba 467 

Mattawa  River 233,  262 

Mauvaise  Butte,  North  Dakota 171 

Mauvaise  Coulee,  North  Dakota 176,  268,  595 

May  ville.  N.  Dak 436,  534, 535,  572,  631 

Meillicott,  H.  B..  cited 513,547 

Meek,  F.B.,  cited 81 

Mckinock,  N.  Dak 139,  456 

Mennonite  Reserve,  Manitoba 526, 607 

Merjelen  See 192,194 

Merrill,  F.  J.  H.,  cited     263,264 

Mesabi  moraine 32, 146, 177-179,  213,  243,  306 

Mesabi  Range,  Minnesota 30,  31,  32, 177 

Mothy  Portage 64,231,232,275 

Michigan,  Lake,  compared  with  Lake  Agassiz 200, 

203,  240,  288,  318,  421 

Middle  River,  Minnesota 585 

Midway,  Manitoba 449 

Mille  Lacs,  Minnesota 159 

Millwood  series 83 

Milne,  John,  cited 112 

Milnor.N.Dak 149,211,311 


654 


INDEX. 


Page. 

Milnor  beach 211,  223, 310, 312, 328 

MiltoD,  K.  Dak 93, 175 

Miiineapolis,  Minn 139,  210,  243,  641 

Minnesuta.  hi»;:Iie.st  laiul  iu 31 

origin  of  iiaiiK' 15 

topography  of  northern 30 

Minnesota,  glacial  lake 35,  142,  254,  264 

Minnesota  Geological  Surrey, work  on  Lake  Agassiz 

and  adjacent  moraines 7, 139. 

142, 147, 159, 163,  177,  551,  555,  557 
Minnesota  lobe  of  ice-sheet. .  130, 141,  208,  212, 264, 336, 350,  635 

Minnesota  Kiver 15,  66,  130,  254,  264,  427,  443 

Minnesota  Valley 16, 142, 189. 197.  222,  224,  265,  317,  6U5 

Minnewaukan,  N.  Dak 158, 169, 171 

Minot,  N.  Dak 173, 601 

artesian  wells 574 

Miocene  formation 85 

Mirage  in  Ked  River  Valley 21 

Missinaibi  lake  and  river 204, 508 

Mississippi  River,  analysis  of  water 543 

Mississippi  Valley,  erosion  of 107 

Missouri  River  in  preglacial  time 106 

Mitchell,  Minnesota 428, 429, 554 

Modified  drift 127.  143,155.170,  170-190.210,222, 

239,  242,  262,  265,  269,  270,  308,  316.  334,  378.  552 

projjortion  iu  deltas 189,291 

Molluscan  fauna  of  Lake  Aga&aiz 4,237 

Mono,  Lake 193,194 

Montana  formation 82 

Montgomery,  H.,  cited 539 

Montreal,  Canada 202,231,262,263 

Mooreton,  N.  Dak 414, 566 

Moorhead,  Minn 22. 55, 133, 211, 218, 613,  627 

section  of  deep  well 556 

weather  records 592-600 

Moose  !Noso,  Manitoba 184 

Moraines,  marginal,  of  the  iccsheet 10, 11,21, 109, 

134, 136, 139-179,  201.  208,  210.  215,  341,  472,  559.  583 

contemporaneous  with  the  Herman  Beach . . .  214, 

235, 245, 250,  498 

short  time  required  for  their  formation. .  242,  245 

Morden,  Manitoba,  deep  well 74,  81,  534,  536,581 

beaches  near 423, 448, 453 

Morris,  Manitoba 133,  220, 471 

Mossy  portage 219,  468,  470,  477 

Mossy  River,  Manitoba 61 

Mounds,  aboriginal 284, 

313,  347,  349,  354,  390,  412,  413,  431,  611,  643-646 

Mountain,  N.  Dak 419,420 

Mountain  City,  Manitoba 365,  393,  440 

"Mountains"  ea.st  of  the  Golden  Valley 349,352,392,437 

Mountain  building  duriug  the  Pleistocene  period 513, 

517,519 

Mouse  (Souris)  River 42,59,85,158,268 

Mowbray.  Manitoba 269,  270,645 

Miiir  glacier,  Alaska 243,  247 

Muskegs 29,  31,  586 

Muskoda.  Minn 290,292.410,643 

Mustinka  River 45,  21 1,  279,  396, 630 

N. 

Namekan  Lake,  Minnesota,  lignite 630 

Nanaen,  F.,  on  the  Greenland  ice-sheet 123, 124 

Natural  gas 563,  571,  631 

in  well  water 553, 569 

Neche,  N.  Dak 463, 469, 576 


Page. 

Neepawa,  Manitoba 134, 370, 371, 394, 580 

Neill,  E.  D.,  cited 15 

Nelson,  Manitoba 406,422,440,581 

Nelson  River.. 29,62,67,198,214,220,252,473,631 

erosion  during  i)Ostglacial  time 221,226 

glacial  stria- 634 

terminal  moraine  crossing 140,215 

Newbeny,  J.  S.,  cited 7,261,  263 

Niagara,  N.  Dak 168,338 

Niagara  formation 72,73,79,80 

Niagara  River 232  257 

Nicollet,  J.  N.,  cited 15^  157 

on  the  Coteau  des  Prairies 37 

N  iobrara  formation 81.  82,  84.  86,  00,  91,  96,  98, 106,  394 

Nipigon,  Lake,  glacial  striae ggg 

Nipissing,  Lake 233 

Niverville.  Manitoba 133,471,577 

Niverville  beaches 217,  220,  226,  227,  234,  236,  471^73, 479 

Norcross,  Minn 334 

Norcross  beaches 214,  216, 221,  223 

224,  234,  236,  295,  298,  316,  334,  383-396,  475, 482,  484 

Nordeuskiold,  A.  E.,  on  the  Greenland  ice-sheet 123, 195 

North  Saskatchewan  River 62,215,272 

Northern  Pacific  Railroad 39 

160,  290,  321, 410, 430,  435,  446,  450, 613 

Northwood,  N.  Dak 334  573 

Norwood,  J.  G.,  glacial  striai 639 

Noyes,  "W.  A.,  analyses 537 


O. 


Oak  Hummock,  Manitoba 

Oats,  statistics  of  production 590 

Ochre  River,  Manitoba 

Odanah  series 

Ojata,  N.  Dak 460,461, 

Ojata  beaches 218,  222.  226,  459-462, 

Ojibway  Indians 29.  52.  54.  57. 163. 173. 177,  535, 

Ontario,  Lake,  during  departure  of  the  ice 203, 

Orange  Ridge 8,395,425, 

Urr  station.  North  Dakota 346, 

Osars 


-  184 
615, 619 

449,  477 
83 
573, 587 
479,  483 
610,  611 
233, 257 
444, 610 
391, 403 

-  179 


Ossowa,  Manitoba 459 

Ossowa  beach 219,226,468-470 

Ottawa  River  basin,  epeirogenic  movements 3 

231,232,262.263,505 

Ottertail  Lake  and  Riv^r 52,54,632,643 

Outlets  of  glacial  lakes 195,  231.  232,  250 

Overwashed  gravel  and  sand 143, 155, 170,182 

Owen,  D.  D.,  cited 6,52,71 

early  observations  of  Lake  Agassiz 6,360 

Ox  Creek,  North  Dakota 172,173,642 

Oxidation  of  the  till 135 


Packard,  A.  S.,  cited 112,505,508 

Pakowki,  Lake 205,273 

Paleozoic  bowlders 136^  jge 

formations 65,  72,  73, 74, 425 

Palliser,  John,  early  observations  of  Lake  Agassiz 6, 

360, 644 

Panama,  Isthmus,  epeirogenic  movements 513 

Panton,  J.  H.,  observations  of  glacial  stria? 635, 636 

on  depth  of  Lake  "Winn  ipeg 47 

rocks  of  Manitoba 69,71,72 

section  of  drift  at  Winnipeg 577 


INDEX, 


655 


Page. 

Parallel  Eoads  of  Glen  Eoy 5 

Park  Kiver,  N.  Dak 56, 

93,  95,  220,  336,  342,  353,  419, 437,  535,  575,  587,  631 

Pasquia  Hills 35,43,61,99.  179.273 

Patagonia,  glaciation  of 509,512 

Peac„,  glacial  lake 64,208,255,274 

Peace  River 63, 120, 121. 123,  208, 041 

Peary,  EE,,  on  the  Greenland  ice  sheet 123,124  I 

Pelican  Lake,  Manitoba 57,176,197,269,377 

Pelican  River,  Minnesota 55.631,632 

Pembina,  N.Dak 24,213,612,627,643 

origin  of  name 57 

Pembina  delta 27, 

189,  357-363,  392,  404,  407,  421, 438,  452,  548,  549.  630 

PembinaMountain 27,35,40,83,93.95,97, 

105, 134, 178, 198,  213,  355, 360,  363,  404, 422, 439,  589 

Pembina  River 41 , 

56,  57, 93, 138, 189, 197,  268,  270,  357,  360, 457,  631 

Pembina  trail 297,299,412,413,432,433 

Penck,  A.,  cited 489 

Peoria,  Lake 198 

Pepin,  Lake 19 

Perched  bowlders 136 

Petroleum  in  Cretaceous  atrata 98 

Phillips,  John,  cited 494 

Pilot  Knob,  North  Dakota 175,341 

Pilot  Mound,  Manitoba 99, 138,  645 

PilotMound,  North  Dakota 162 

PineEiver,  Manitoba 396,406,442,477 

Plain  of  the  Red  River  Valley 21, 

133,  310,  366, 417,  526,  590,  593,  645 

Plains  of  the  Northwest 85, 86, 102, 151, 274, 360, 547,  603 

Plasticity  of  the  earth's  interior 495, 500, 518,  519,  521 

Playgreen  lakes 63,  68, 238 

Pleasant  Home,  Manitoba 468,  469, 578 

Pleasant  Ridge,  Minnesota 446 

Pleistocene  lakes,  two  classes 192,207,240 

Pleistocene  mountain-building 513 

oscillations  of  land  and  sea 501, 

509,  512,  513,  515,  520 

Pleistocene  period 128,  509, 612, 514, 517, 519 

Pliocene  erosion 102,104,105 

Plum  Creek,  Manitoba 271,581 

Pokegama  Falls,  Mississippi  River 31,32,178 

Pokegama  Lake,  Minnesota 33, 173 

Pomeroy ,  Manitoba 462 

Poramede  Terre  River 19 

origin  of  name 611 

Poplar  River,  Minnesota 165 

Population  statistics 617, 618 

Porcupine  HiUs 35,43,58,61,83,99, 179 

Portage  la  Prairie,  Manitoba 133, 371, 467,  579 

Portland,  N.  Dak 334,  418,  436,  572 

Postglacial  period 198, 238, 487, 507, 508, 511 

Potatoes,  statistics  of  production 622 

Powell,  J.  W.,  cited 104, 494 

Prairie,  causes  of  limitation 604 

Prairie  and  forest  fires 604,605 

Prairie  partsf  Lake  Agassiz 1,29, 

30,  44, 46,  583,  591,  602,  613,  618 

Pratt,  J.  H.,  referred  to 493 

Preglacial  contour 107, 133 

Preglaoial  elevation 501, 502,  504, 510, 519 

Preglacial  erosion 38, 

59, 175, 198,  269,  270,  317,  363,  405,  422,  501-504 

Preglacial  residuary  detritus 132,515 

Preglacial  river  channels 17,  ]  06, 145, 170, 172,  222,  317 


Page. 
Preston.  E.D.,  cited 490 

Prostwich,  J. ,  cited 243,  518 

Prince  Albert 273 

Profiles  across  beaches . .  429, 431, 432,  435,  436, 437,  439, 440,  441 

of  railways 8 

Provo  shore  line  of  Lake  Bonneville 194 

Publications  relating  to  Lake  Agassiz  previous  to  this 

monograph 11 

Pumpelly,  R..  cited 515 

Q- 

Qu' Appelle  River 58, 59, 179, 189, 197,  268,  271, 273 

glacial  lake 206,268 

Quaternary  baseleveling 103, 105, 199 

epeirogenic  movements 229, 474-522 

Quebec,  Canada 262.  264 

Queen  Charlotte  Islands 127,231,506 

E. 

Rabbit  River.  Minnesota 45, 398 

Railway  profiles 8 

Rainfall 195,542,545  592,594,595.605 

Rainy  Lake 24,  32,  49,  50,  67, 137,  388,  586,  630,  644 

area,  elevation,  and  depth 49 

glacial  strias 638,640 

Eainy  River 50,181,388,586,631,632 

aboriginal  mounds 644 

glacial  strife 639,640 

Eamseys  Groves,  North  Dakota 342 

Rat  Portage,  Ontario 51 

Recent  period 128,  238,  487,  512 

Recession  of  the  ice-sheet 126,130, 167,191,195,203, 

209,  214,  216,  229,  238,  247,  265.  298,  444, 481,  521,  596 

Red  Lake 32,  49, 175,  178. 181 .  209,  213,  303,  586,  630,  643 

area  and  elevation 49,304 

origin  of  name 52 

Red  Lake  Falls,  Minn 54,411,632 

Red  Lake  Indian  Reservation 164, 303 

Red  Lake  River 52,  242,  463,  582,  631,  632, 643 

Red  River  of  the  North 20,  45,  54,  65, 107, 126. 130, 163,  202, 

205,  242,  284,  446,  450,  582,  631,  632,  644 

analyses  of  water 540,  541,  544 

dates  of  opening  and  closing  of 

navigation 599 

Red  River  Valley,  area  of  Lake  Agassiz 5, 35, 133, 135, 

159,  185,  202,  209,  266,  276,  306,  417,  554,  613 

artesian  and  common  wells 523-581 

climate w 545 

drainage 428, 459,  585 

erosion  of 104 

flora  582,601-610 

fluvial  deposits 253 

marshes S84-587 

topographic  features 19,  39 

tract  of  till  across 159,166 

Reelevation  from  the  Champlain  subsidence 507, 520 

Reid,  H.F.,  cited 243.247 

Reindeer  Lake 545,637 

Relationship  of  the  earth's  crust  to  the  interior 493, 519 

Reynolds,  N.  Dak 159,165,452,455 

Rheinland,  Manitoba 458.581 

Rhythmic  stages  of  elevation  and  outlet  erosion 224. 

235,250,251,444,499 

Richardson,  John,  cited 68.  231, 275 

Richthofen,  F.  v.,  cited 515 

Ricketts,  C,  cited 513 


656 


IKDEX. 


-Ridge,    east  of  Elk  Valley 

'"Kidge,"  euat  of  Emerson,  Manitoba 

Kidiog  Mountain 1,  35,  4t 

83,  99, 105,  179,  198,  378,  395,  406, 426, 

northward  ascent  of  beaches 

Rivers  of  the  Lake  Agassiz  area 

Rock  Lake,  Manitoba 138, 

Eo'eky  Mountains,  glaciation  of 117,120,121, 

Rocky  Spring  plateau,  Montana 

Rolette,  Minn 

Rome,  N.  Y 

Rose  Ridge 

Roseau  Lake,  Minnesota 47, 175, 

Roseau  River,  Manitoba 66, 181, 401, 433, 

Rosenfcld,  Manitoba,  artesian  well 74,  78, 133, 536, 

Roy,  Thomas,  cited 

Rush  River,  North  Dakota 

Russell,  I.  C,  cited 111.  128,  207, 

on  Lake  Lahontan 

Rye,  statistics  of  production 


Page. 

348, 437 
465,  469 
i,  45,  61, 
477.  589 
.  235 
50 
197,  269 
123,  2T4 
.  118 
.  296 
258,  260 
441,  610 
401,  586 
578,  630 
538,629  i 
.  260 
417,  385 
521,  598 
.  193 
.   620 


S. 

Sabin,  Minu s 446,555 

Saguenay  River 102,501,505 

Salisbury,  E.  D.,  cited 132,498,517,518 

Salt  and  saline -waters 75, 

100, 169,  524,  527-536,  546,  561,  565,  573,  587,  628 

Salt  Cooley  and  River,  North  Dakota 587 

Sand  for  masons'  use 628 

Sand  Hill  dulta.    27, 165, 189,  298,  386,  400,  591 

Sand  Hill  River 45,  56, 164, 165,  297,  298, 411,  459,  585 

Sargent  County,  N.  Dak.,  glacial  lake 148, 149, 152, 266 

Saskatchewan,  glacial  lake 6, 

59,  60, 179, 189, 197,  2U6,  255,  267, 272-274 

Saskatchewan  River 44,45,61,205,215,217,586 

Grand  Rapids  of 219, 

220,  236,  445,  471,  472,  477,  631 

Sawkins,  J.  G.,  cited 513 

Saxicava  sands 508 

Scandinavia,  epeirogenic  movements 511 

fjords 510 

glaeiiil  lalces '5 

Scarboro  Heights,  Ontario 198,261 

Schookraft,  H.  R.,  cited 173 

Schott,  C.  A.,  cited 491 

Scotland,  gkaciatiou  of 125 

Scratching  River,  Manitobaj 56 

Scribner,  F.  L..  cited 609 

Second  Pembina  Mountain 41,96,355,356 

Sections,  across  beaches 26, 

421,  429, 431,  432, 435, 436,  437, 439, 440, 441 

the  Red  River  Valley 22,23,24 

artesian  w  ells 74,  548-581 

Coteau  des  Prairies 38 

of  Birds  Hill 185 

of  deltas 290,  298,  316,  334,  358,  373 

showing  sources  of  artesian  well  waters . . .       527 
decline  of  water  head    of  artesian 

wells 532 

Sections,  order  in  townships  in  the  United  States  and 

Canada - 11,12,276,549 

Selkirk,  Lord,  founding  colony  in  Manitoba 612, 616,  628 

Selwyn,  A.  R.  C,  cited 71,98 

Shakopee  limestone 17.76 

Shaler,  N.  S.,  cited 78,493,495,498,605 

Shanty  Creek,  Manitoba 426,442,477 

Sheldon,  N.  Dak 315,317 


Pa,:,e 

Sberbrooke,  N.  Dak 161 

Sheyenne  delta 27,57,150,189, 

202,  211,  212,  223,  268,  312,  315-317, 402,  415,  434,  591 

Sheyenne  River 56.  91, 134, 137, 148, 151, 153, 

155, 161, 171, 177,  312,  314,  596,  612,  030,  631 

glacial 149,150,161,210 

Shirley,  Minnesota 454,459 

Shoal  Lake,  Manitoba 8,134,241,467 

Shorelines  . .  3.  13,  26,  43, 196,  199.  221,  231,  234,  260,  261,  276-473 

tabular  list,  with  altitudes 476 

Shrubs,  species  of 603,604 

Sibley,  Lake,  North  Dakota 145 

Sideuer,  C.  F.,  analyses 537 

Signal  Service  records 592-601 

Silurian  formations 17,  68, 72,  80, 157,  535,  536,  588 

Sims,  N.  Dak.,  lignite 85,630 

Sipi-wesk  Lake,  Nelson  River 63 

Sisseton  Agency,  S.  Dak 86 

Skunk  Lake,  North  Dakota 149,150 

Sleepy  Eye,  Minn 90 

Sloughs 329,343,354,584-587,590,607 

Smock,  J.C.,  cited 117 

Snake  River,  Minnesota 56,412,413,433,585 

Snowfall 592,594 

Sogne  fjord 126 

Soils,  variety  and  distrib  ution 583-591 

Souris,  glacial  lake 6,57, 

149, 157, 172, 177, 189, 197,  206,  255, 267,  363,  641 

Souris  River 42, 

59,  60,  85, 158, 173, 176, 178,  269,  612,  630,  631,642 

aboriginal  moujlds 644 

South  Saskatchewan  River 61, 267,  272 

Cretaceous  series 82 

Southall,  J.  C  cited 238 

Spencer,  J.  W.,  cited 203,  217,  255,  257, 258,  261,  502, 629 

tSpiritwood  lakes,  North  Dakota 145 

Spit  beach  deposits 318,366,450 

Springs , 286, 

361,  385, 429,  439,  459,  531,  533,  .536,  549,  563,  585,  587 

saline 535,565,587,628,629 

Square  Plain,  Manitoba 442,477 

Squirrel  Creek,  Manitoba 587 

St.  Boniface,  Manitoba 133,577,627 

St.  Croix,  Lake 19,198,256 

St.  Croix  series 74,78 

St.  Elias,  Mount,  glaciers 138,521 

St.  Hilaire,  Minn 387,  400, 412,  432,  561,  627 

St.  Joseph,  N.  Dak 457 

St.  Lawrence  formation — 74,  78 

St.  Lawrence,  glacial  lake 254,  262,  263 

St.  Lawenee  Valley,  epeirogenic  movements 3, 127, 

231,  232,  259,  506 

glacial  currents 126 

St.  Martin,  Lake 47,636 

St.  Paul,  Minn 139,210 

weather  records 592-600 

St.  Peter  sandstone 17,70,76,78,80 

St.  Thomas,  N.  Dak 463,575 

St.  Vincent.Minn 24,133,213,565,613 

analysis  of  water  of  Red  River 541, 

544, 547 

weather  records 593-600 

Stages  of  Lake  Agassiz 210, 250, 444, 474, 476 

the  Glacial  period 110, 141, 167, 210,  280, 506, 554 

Standing  Rock  Hill,  North  Dakota 153 

Star  Mound,  Manitoba 99,137,645 

.Stock  raising 621,624 


INDEX. 


657 


stone,  G.H.,  cited 180,505 

Stonewall,  Mauitiiba 72,  470,  578,  626,  636 

Stonewall  beach 217,  219,  220, 226,  470,  479 

Stony  Mountain,  Manitoba 71 ,  72,  469,  626,  636 

Stony  Kidge,  Minnesota 174 

StiatiBed  diift 127 

Stria-,  glacial 108, 115, 129, 130, 132, 182,  234,  239 

deflected 633,  635,  637.  639,  641 

table  of 129,  633-642 

Stump  Lake 102,  169. 170,  209,  644 

fluctuations 595,597 

Subglacial  drift 136 

Subsidence,  epeirogenic,  of  the  Cliani plain  epoch 127, 

229,  263,  505,  510,  519 
J^ake  Aga.'ssizand  Hud- 
son Bay  region 3, 127, 

229,  505.  519 

SuUys  Hill,  North  Dakota 157,169 

Superglaei.ll drift 191,  250 

Superior,  Lake,  during  departure  of  the  ice.  -  198,  203,  217,  250 

analysis  of  water 544.  545 

glacial  striiu 637,  640 

Swamps 29,31,304,413,586 

Swan  Lake,  Manitolia 73, 197,  217,  269,  454 

Swan   Kiver,  Manitoba 97,90,210,442,449,453,477 

Swan,  AV.  E.,  Rosen feld  artesian  well 79 

Sweden,  epeirogenic  movements 511 

Sweet  tirass  Hills,  Montana,  glaeiation 117, 118 

T. 

Tamarack  Eivor,  Minnesota 50,  304,  413,  433,  450,  563,  585 

Tanberg,  Minnesota - 2S6,  385,  399,  587 

Taylor ,V.  B.,  cited 257, 261 

Taylor  Lake,  North  Dakota 147, 150, 160,  210,  309 

Temperature 598 

changes  of,  in  e.arth'.s  crust 491, 522 

Terminal  moraines 10, 11 ,  109,  134, 136, 

139-179,  201,  208,  210,  215,  341,  472,  559,  583 
contemporaneous  witli  the  Herman 

beach 214,  235,  245,  250,  498 

short  time  required  for  their  forma- 
tion  242, 245 

Terrace  epoch 128 

Terraces,  along  base  of  I'embina  Mountain. . ,  41, 135,  404, 422 

deposits  of  beach  gravel "---  344,300,365,422 

of  modified  drift  in  \'alleys. . . .  127, 162, 180,  222,  270 

shore-lines  of  erosion 26,198,261,323,411 

Tertiary  baseleveliug 102,  104, 199,  510,  528 

formations 85,  88, 112 

Tewaukon,  Lake,  North  Dakota 149 

Thibet,  epeirogenic  movements 514,  515 

Thickne.ssof  the  drift 16,  133,137 

ice-sheet 112,117,505 

Thief  Lake,  Minnesota 47,586 

Thomson,  W.,  cited 490,493 

Thornhill,  Manitoba 137,175,213,304,393,645 

Three  Buttea,  Montana,  glaeiation  of 117,118 

Thunders  Nest 309 

Tiger  Hllla 42,44,99,130,134, 

140, 175, 176, 178, 271,  366,  368,  377, 406,  580,  589,  645 

Till 40,108,119,122, 

134,  201,  241,  250,  253,  260,  369,  381,  506,  583,  588,  589 

eiiglacial  and  subglacial 136 

mass  in  esker  gravel 186 

superglacial 191,  250 

tract  crossing  the  Red  River  Valley 159, 166 

Tintah,  Minn 307,  551,  630 

MON    XXV 42 


Page, 
Tintah  beaches . .  221,  224,  234,  298.  316,  334,  387,  396-406,  482,  643 

I  Toad  Mountains,  Minnesota 163 

Tobacco  Creek,  Manitoba 587 

Todd.J.E.,  on  Lake  D.-ikota 251,206 

preglacial  courses  of  rivers  in  North 

Dakota 106 

terminal  moraines 140 

Tongue  Elver,  North  Dakota 58,93,357,421,457,468,470 

Topography  of  the  basin  of  Lake  Agassiz 14, 

151,  175, 198,  221,  269,  272,  339,  602 

Tombs,  J.,  Grafton  artesi.an  well 77 

Toronto,  Ontario 198,261 

Totteu,  Fort,  N.  Dak 156,157,109,644 

Tower  City,  N.  Dak.,  artesian  well 100,  161 

Townships,  subdivision  in  sections 11,12 

Tracy,  Minn.,  sectionof  well 88,89.90 

Transportation  of  bowlders 109, 115, 130, 191 

Traverse,  Lake 15. 17, 18,  45, 143, 

198,  208,  211  222,  224,  236,  265,  279,  306,  427 

aboriginal  mounds 643 

Trees,  species  of  forest 45,  299,  304,  343,  389, 413,  602,  603 

cultivation 277 

Trehemc,  Manitoba 42, 178,  366,  393,  406,  580 

Treherne,  H.  S.,  leveling 48,  59 

Trenton  limestone 17,  70,  74,  75,  76,  78.  SO 

Turtle  Mountain 10,  36, 

85,  102, 105,  130, 162, 173, 175,  176,  209, 243,  268,  630 

Turtle  Kiver,  North  Dakota 50, 

93,  96,  333,  338,  345,  390,  403,  418,  574,  031 

Twining,  W.  J.,  cited 208 

Two  Rivers,  Minnesota 50, 401.  628,  630,  643 

Tyrrell,  J.  B.,  cited 61,118,119, 

196,  215,  220,  234,  237, 24 1 ,  396,  406,  486,  534 

Manitoba  escarpment  named  by 35 

observations  of  glacial  stria- 635,636 

on  Riding  and  Duck  mountains 43 

origin  of  name  of  Lake  Manitoba 48 

rock  formations  of  Manitoba- . .  70,  72,  73,  83.  98 

well  at  Deloraine,  Manitoba 529 

Morden,  Manitoba 81 

work  on  Liike  Agassiz  in  Canada 10, 

217,  235,  395,  426,  442,  444,  449,  453, 
458,  462,  464, 468,  470,  472,  477,  479 


IJlrich,  E.  O.,  cited 69 

Union  Slough,  Iowa ■- 264 

United    States     Geological  Survey,    work    on    Lake 
Agassiz - 7 

Uplift,  epeirogenic,  of  the  Lake  Agassiz  and  Hudson 

Bay  region 3,  147,  217,  224,  227,  234,  329,  382, 

386,  407,  427, 428, 442,  444,  450,  451, 454,  474-522,  596 

rhythmic  stages  of 224,  235.  444.  499 

wavelike  advance 481,486.522 

Upj>er  Silurian  formations 72,  74,  79,  80 

Utica  shale  formation 71 


Valley  City,  N.  Dak 151,154,161 

Valley  River,  Manitoba 235,  395,  406,  426,  412,  477 

Vasey,  G..  cited 608,609 

I   Vegetables,  notes  of  production 590,623 

Vermilion  Lake,  Minnesota 31,32,137,146,639 

Vermilion  moraine 146, 177 

Vermilion  River.  Manitoba,  deep  borings 83,84,99 

beach  ridges  near 442 

Vermilion  River,  South  Dakota,  artesian  wells 528 


658 


INDEX. 


w. 

Page. 

Waconia  moraine 142-146, 147, 152, 208, 210, 2G5 

Wadsworth,  SI.  E.,  cited 494 

Walipeton,  N.  Dak 22,  55.  211,  565 

Wakott,  C.  D.,  relerred  to 76 

Waltott,  N.  Dak 4.'?4,  560 

Palilalia,  N.  Dak 27,360,361,421,453 

Wallace,  A.  R.,  cited 513 

Warren,  G.K.,  cited 106 

on  causes  of  lakes  Traverse,  Big  Stone, 

LaC(iui  Parle,  and  Pepin 18 

survey  of  the  Minnesota  \' alley 6 

Warren,  Minn 463,562,627 

Warren,  N.  Dak.,  deep  well 567 

Warren,  glacial  lake 217.,  255,  257,  258 

Warren,  River,  outlet  of  Lake  Agassiz..  7,15,19,66,150,211 
212,  222,  225,  235,  265.  280.  397,  408.  427,  443, 478,  564 

Washington,  Mount,  glaciation  of 114,124 

Washington  Lakes,  North  Dakota 146,  243 

Watercourses,  now  deserted 53, 

161. 170, 196,  205,  234,  262,  275,  312,  374,  377 

Water  Hen  Lake  and  Kiver 49,61 

Water  power 631,  632 

Water  supply  by  wells 523-581 

alkaline 524 

analyses 536-545 

fresh,  sources  of 526.  576 

saline,  sources  of 527-536,  561,  576 

Weather  records 592-001 

Wells,  analyses  of  waters 536-540 

artesian 2, 13,  74-80.  523-581 

common 358,  441,  523-58i 

sections  of 334,  356,  359,  367,  548-581 

West  Indies,  epeirogenic  movements 513 

West  Selkirk,  Manitoba 133,578 

Westhourne,  Manitoba,  aboriginal  mound 645 

Western  Erie  glacial  lake 257 

Western  Superior  glacial  lake 256 

Wheat  raising 20,  417,  523,  584,  590,  615-019 

Wheatland,  N.  Dak 321,323,416,435,568 

Wheaton,  Minn 15U.  39li,  550 

Wliite,  C.  A.,  referred  to 82,  94.  99 

Whiteaves,  J.  P.,  cited 70,71.73,83,98,89 

White  Earth  Agency,  Minn 32,33,45,156,164,295,303 

White  Mountains,  glaciation  of 113, 124,  505 

White  Rock,  S.  Dak....   138,150,211,280,388,396,408,427,428 

White  silts 207 

White  Stone  Hill,  North  Dakota 152 

Whitemouth  River,  Manitoh  1 52,134 

Whitney,  J.  D.,  cited 494,515,005 

Whittle,  (J.  L.,  cited 202 

Whittlesey,  C,  cited 261,498,595,639,640 

Wild  Rice  River,  Minnesota 53,56,242,295,296,584,631 

origin  of  name 611 

Wild  Rice  River.  North  Dakota  . .  45,  56,  267,  3U9,  310,  565,  612 

Williamson,  A.  W.,  cited 15.17,18,397,460 

Willow  River,  North  Dakota 173,  641, 642 


Page. 

Winchell,  A.,  relerred  to 605 

Winchell,  Horace  V.,  assistcnt 7 

cited 1 00,  304,  625 

glacial  striiE 640 

Winchell,  N.  H.,  cited...  87,100,177,305,525,537,556,629,631 
attributing  Lake  Agassiz  to  harrier 

of  the  ice-sheet 7 

Cretaceousformations  in  Minnesota-       87, 

K8, 101 

observations  of  glacial  striie 039,  640 

on  Giants  and  Mesabi  ranges 31 

on  nieasiirenient  of  postglacial  time.       238 

section  of  Humboldt  well 75 

Rosen  feld  well 79 

Winds 277,  299.  309,  395,  600 

records  of  mean  velocity 000 

Windy  Mound,  head  of  the  Coteau  des  Prairies 150 

Winnebagoshish,  Lake 32,178,213,630 

AA'innipeg,  Manitoba 25, 

55,  68,  133,  156,  213,  526,  576,  612,  027,  044 
general  section  of  drift  deposits-  -      577 

wea tiler  records 592-599 

Winnipeg,  Lake. . , 1,  3, 25, 45, 47, 52, 02, 67, 

68,  69,  70, 137, 198,  213,  215,  220,  241,  443,  472 

area,  elevation,  and  depth 47 

I  glacial  strias 635 

present  representative  of  Lake  Agas- 
siz    220,226 

Winnipeg  River 50,  51.  582,  031,  632,  638 

Winnipegosis,  Lake 34,  43,  48.  61,72,  73,  97.  2 IB,  470.  629 

area  and  elevation 48 

glacial  stria' 636 

Winter,  climatic  efl'ects  on  Lake  Agassii 250,252,278 

Wisconsin  stage  of  Glacial  period 109.110.141,208 

Wolff,  J.  E.,  cited 103 

I   Wood.  J.  W.,  jr.,  cited 103 

Wood,  in  intcrglarial  IVu-est  bed 555.  556 

Red  River  Valley  alluvium 555,  560,  574 

till  and  modified  drift 558,  559 

j   Wooded  region  of  northern  Minnesota  anil  Manitoba.-       29, 

279,  300,  387.  413,  583,  580,  .'i93 - 
Woods,  Lake  of  the. ...29,  49,51, 07,137,  181,198.210,388,402,586 

area,  elevation,  and  depth 49,304 

glacial  stria; 639 

I   Woodward,  R.  S.,  investigation  of  ice  attraction 223, 

489,  492 

Wright,  G.  F.,  Ice  Age  in  North  America 11 

on  duration  of  the  postglacial  period  ..      238 

on  the  Muir  glacier 243 

Wyndmerc,  N.  Dak 266,310,566 

T. 

Yankton,  S.  Dak 208,530,532 

Young,  N.  Dak 356.392 

Young,  Robeit  H.,  assistant 7,8,327.645 

Yukon,  Pleistocene  lake 207 

Yukon  River 207 


